Chapter 4: Igneous Rocks and Intrusive Activity, Chapter 5 Volcanoes and Volcanic Hazards, Chapter 6 Weathering and Soils, Chapter 7 Sedimentary Rocks, Chapter 8 Metamorphism and Metamorphic Rocks

Pressure, which also increases with _________, influences the melting temperature of rocks.

depth

Soils

nonrenewable resources

Most often, however, melting is _____ complete.

not.

Pyroclastic flows are also called ______________ _________________. These fiery flows are capable of racing down steep volcanic slopes at speeds that exceed 60 miles per hour.

nuee' ardentes (glowing avalanches)

In times, these quartz grains may become lithified to form the sedimentary rock______

sandstone

metamorphic aureole

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migmatite

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muscovite

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mylonite

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natural gas

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nitrogen cycle

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nonfoliated

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Stromboli is well known for eruptions that eject incandescent blobs of lava that it has been referred to as the __________ of the ______________.

"Lighthouse of the Mediterranean"

Because there are a variety of ways that the products of weathering are transported, deposited, and transformed into solid rock, ____ categories of sedimentary rocks are recognized.

3

Frost wedging

After water works its way into the cracks in rocks, the freezing water enlarges the cracks and angular fragments are eventually produced.

When the head of a superplume reaches the base of the lithosphere, _______________ melting progresses rapidly.

Decompression

This same process can also contribute to crumbling roadways where salt is spread to melt snow and ____in winter.

Ice

Other examples of how unloading occurs:

In deep mines, large rock slabs have been known to explode off the walls of newly cut tunnels.

and the copper ores of _______________

Michigan's Keweenaw Peninsula

Why does rock weather?

Response of Earth materials to a changing environment

Included in this group are gold deposits of the Homestake mine in _________________

South Dakota

secondary enrichment

The concentration of minor amounts of metals that are scattered through unweathered rock into economically valuable concentrations by weathering processes

The mechanisms that generate these mantle-derived magmas are essentially the same as those that create volcanic island arcs.

The most significant difference is that continental crust is much thicker and is composed of rocks having higher silica content than oceanic crust.

As the slab sinks deeper into the mantle, the increase in temperature and pressure drives water and carbon dioxide from the oceanic crust.

These mobile fluids migrate upward and reduce the melting point of hot mantle rock sufficiently to trigger some melting.

Foliated Textures

Various types of foliation exist, depending on the grade of metamorphism and the mineralogy of the parent rock.

basalt porphyritic

When it is porphyritic, basalt commonly contains small light-colored feldspar phenocrysts or green, glassy - appearing olivine grains embedded in a dark groundmass.

Composition

another factor influencing volcanic behavior is the composition

Most magma that erupts at Earth's surface is ___________ in composition and has a temperature of 1000 - 1250 C

basaltic

Near Earth's surface, rock behaves like a -_____ solid

brittle

Pegmatites contain some of the least abundant ______________________.

elements

The shape of sand grains can also help decipher the history of a sandstone. When streams, wind, or waves move sand and other larger sedimentary particles, the ______lose their sharp edges and corners become more rounded as they collide with other particles during transport.

grains

viscosity

magma's mobility

Eventually, all of the ___________ is transformed into a solid mass of interlocking ____________ ________________ that we call an ______________ ____________________.

melt silicate minerals igneous rock

While both of these mechanisms flatten mineral grains, the ____ remains the same

mineralogy 1. solid-state flow 2. pressure solution

Volcanic necks are also called ________________.

plugs

Coal fields are widespread and contain supplies that should last for hundreds of years.

Although coal is plentiful, its recovery and utilization present a number of challenges. Surface mining can turn the countryside into a scarred wasteland if careful and costly reclamation is not carried out to restore the land. Although underground mining does not scar the landscape to the same degree, it presents significant risks to health and safety.

This active zone consists in part of a chain of continental volcanoes that are distributed along the west coast of the _______________.

Americas, including the large cones of the Andes in South America and the Cascade Range of the western United States and Canada.

Rocky shorelines and _____ regions are common settings for this process.

Arid

Extraordinary amounts of lava have been extruded along fissures in a relatively short time. The voluminous accumulations are commonly referred to as __________ _______________ because most have a ________________ __________ and tend to be rather flat and broad.

Basalt plateaus Basaltic composition

Much of the world's copper is extracted from disseminated deposits, included those at Chuquicamata, Chile, and the huge ______________________ Canyon copper mine in Utah

Bingham

It begins when sea sprays from ___ ____ or _____ ______ penetrates crevices and pore spaces in rock.

Breaking waves Salty groundwater

whereas the ____________________________ Complex in South Africa, contains over 70 percent of the world's known reserves of platinum

Bushveld

Eventually the limestone may be exposed at Earth's surface, where chemical weathering will cause the carbon stored in the rock to be released to the atmosphere as ____.

CO2

Mechanical weathering breaks rocks into smaller pieces and this aids _____________ weathering

Chemical

The lead, zinc, and silver ores near __________ _________________________

Coeur d'Alene, Idaho

Earth's most picturesque yet dangerous volcanoes are _________________________ ____________________

Composite volcanoes, also known as stratovolcanoes

The first lava flow came from a fissure that opened just north of the ______________________________________.

Cone, but after a few months, flows began to emerge from the base of the cone.

As hot rock rises, it experiences a decrease in _______________ pressure and undergoes melting without the addition of heat. This process is called decompression melting.

Confining

Volcanism associated with convergent plate boundaries may also develop where slabs of oceanic lithosphere are subducted under continental lithosphere to produce___ __ ___ .

Continental volcanic arc

Although the depth at which mantle plumes originate is a topic of debate, some appear to form deep within Earth, at the ____ ___ boundary.

Core-mantle boundary

Italy's Etna and Stromboli

Display very persistent eruption activity, and molten lava has been observed in their summit craters for decades.

Gneissic texture or banding

During high grade metamorphism, ion migration can result in the segregation of minerals. The dark biotite and amphibole crystals and light silicate minerals (quartz and feldspar) have separated, giving the rock a banded appearance called gneissic texture or gnessic banding. Metamorphic rocks with this texture are called gneiss (pronouced "nice") Although they are foliated, gneisses do not usually split as easily as slates and some schists.

Figure 4.1

During the catastrophic eruption of Vesuvius in A.D. 79, the entire city of Pompeii was completely buried under several meters of pumice and volcanic ash

Because of the severity of the storms, the region came to be called the ___________ _________

Dust STorms , and the period was called the Dirty Thirties

Most of the recent activity on Kilauea has occurred along the flanks of the volcano, in a region called the _____ ____ _______,.

East Rift Zone

In other cases, their importance is related to the physical properties they exhibit.

Examples include minerals such as corundum and garnet, which are used as abrasives.

The process of transporting essentially unaltered magma though 93 miles of solid rock is _____________ and accounts for the scarcity of natural diamonds.

Exceptional

As the overburden is removed, the outer parts of the granitic mass expand more than the rock below and separate from the rock body. Continued weathering eventually causes the slabs to separate and spall off, creating an ____ _____

Exfoliation dome

Rather than build cones, ______________ ____________________ usually emit fluid basaltic lavas that blanket wide areas.

Fissure eruptions

Numerous fissures eruptions have buried the landscape, creating a lava plateau nearly 1 mile thick. Some of the lava remained molten long enough to flow 90 miles from its source. The term _____________ ____________ describe these extrusions. Lava Domes

Flood basalts

It has long been known that when moist soil freeze, they expand or ___ ____, due to the growth of ice lenses.

Frost heave

During the 1930's, large dust plagued the ___ ____.

Great Plains

clastic

Greek means broken rocks that display a clastic texture consists of discrete fragments and particles that are cemented and compacted together

Why do eruptions occur in the interiors of plates?

Hawaii's Kilauea, one of the world's most active volcanoes, is situated thousands of kilometers from the nearest plate boundary, in the middle of the vast Pacific plate.

fluid basaltic magmas tend to generate two types of lava flows known by ________________ names.

Hawaiian names

Thus, rounded grains likely have been airborne or waterborne. The degree of rounding indicates the distance or time involved in the transportation of sediments by currents of air or water.

Highly rounded grains indicate that a great deal of abrasion and hence a great deal of transport has occurred.

The gaseous portion of most magmas makes up ______%

1 to 6 %

Destruction of Pompeii

1. A.D. 79 eruption of Italian volcano we now called Mount Vesuvius 2. entire city of Pompeii near Naples and few thousand of its residents were entombed beneath a layer of volcanic ash and pumice that fell like rain

Example of several young volcanic island arcs border the western Pacific basin, including the 1. 2. 3.

1. Aleutians 2. Tongas 3. Marianas

Examples of shield volcanoes 1. 2. 3.

1. Canary Islands 2. Hawaiian Islands 3. Galapagos 4. Easter islands

Example: Flourite and limestone

1. are part of the steelmaking process, the 2. the abrasives required to make a piece of machinery 3. the fertilizers needed to grow a food crop

Granite

1. best known of all igneous rocks 2. used for tombstones and monuments and building stones 3. found in Barre, Vermont, Mount Airy, NC, St. Cloud, Minnesota 4. coarse-grained rock 5. 10% to 20 % quartz and roughly 50% potassium feldspar 6. quartz appears rounded in shape, glassy, and clear to gray in color. 7. feldspar crystals are generally white, gray, or salmon pink in color, and blocky or rectangular in shape

most gneiss contain lesser amounts of 1. 2. 3.

1. biotite 2. muscovite 3. amphibole

When clay minerals are buried to a depth where temperatures exceed 200 degrees C, they become the minerals 1. 2.

1. chlorite, mica-like mineral formed by the metamorphism of dark iron and magnesium - rich silicate minerals. 2. muscovite mica

To summarize: the weathering of potassium feldspar generates a 1. 2. 3.

1. clay mineral 2. soluble salt 3. silica

Because soil-forming processes operate from the surface downward, variations in 1. 2. 3. 4.

1. composition 2. texture 3. structure 4. color gradually evolve at varying depths

Basic metamorphic environments are: 1. 2. 3. 4.

1. contact or thermal metamorphism 2. hydrothermal metamorphism 3. burial and subduction zone metamorphism 4. regional metamorphism

Other important building materials include

1. cut stone 2. aggregate (sand, gravel, and crushed rock) 3. gypsum for plaster and wallboard 4. clay for tile and bricks 5. cement and aggregates go into the making of concrete, a material is essential to practically all construction

As magma cools and solidifies, these elements combine to form 2 major groups of silicate minerals 1. 2.

1. dark or ferromagnesian silicates = rich in iron and magnesium and comparatively low in silica (olivine, pyroxene, amphibole, and biotite mica are the common dark silicate minerals of Earth's crust 2. light or nonferromagnesian silicates = contain greater amounts of potasium, sodium and calcium rather than iron and magnesium. light silicate minerals including quartz, muscovite mica, and the most abundant mineral group, the feldspars, are richer in silica than the dark silicates

Magma can be generated three ways. 1. 2. 3.

1. decrease in pressure without an increase in temperature can result in decompression melting 2. the introduction of water can lower the melting temperature of hot mantle rock sufficiently to generate magma 3. heating of crustal rocks above their melting temperature produce magma

Describe how lava is emitted from the magma chamber.

1. escaping gases propel it from the magma chamber 2. explosively ejected, producing steam and ash eruptions 3. not all violent; many volcanoes emit quiet outpourings of fluid lava

What has accelerated the rate of erosion?

1. farming 2. logging 3. construction, which remove or disrupt the natural vegetation

why are nonmetallic mineral resources extracted and processed?

1. for the nonmetallic elements they contain 2. physical and chemical properties they contain although these resources have diverse origins, many are sediments or sedimentary rocks

mica schists often contain accessory minerals, some of which are unique to metamorphic rocks. Some common accessory minerals that occur as porphyroblasts include: 1. 2. 3.

1. garnet 2. staurolite 3. andalusite Now the rock is called garnet-mica schist, staurolite-mica schist, or andalusite-mica schist

Granitic (Felsic) igneous rocks

1. granite 2. rhyolite 3. obsidian 4. pumice

It should be pointed out that transported soils form in ___ on parent materials that have been carried from elsewhere and deposited by 1. 2. 3. 4.

1. gravity 2. water 3. wind 4. ice

The agents of metamorphism are 1. 2. 3. 4.

1. heat 2. pressure 3. directional stress 4. chemically active fluids

Why is Earth's interior extremely hot?

1. heat released from the repeated collision of asteroid-size bodies during the formation of our planet 2. energy being continually released by the decay of radioactive elements

Sedimentary rocks

1. information about Earth's history 2. economically important as well 3. associated with important mineral and energy resources

The precipitation of material occurs in two ways 1. 2.

1. inorganic (in = not, organicus = life) 2. organic (life)

Hydrothermal solutions circulating through the seafloor also remove large amounts of metals, such as 1. 2. 3 4. from the newly formed crust

1. iron 2. cobalt 3. nickel 4. silver 5. gold 6. copper

Other granitic laccoliths have since been identified in Utah

1. largest is part of the Pine Valley Mountains located north of St. George, Utah 2. Others are found in the LaSal Mountains near Arches National Park 3. found in Abajo Mountains directly to the north

Volcanoes extrude 1. 2. 3.

1. lava 2. large volumes of gas 3. pyroclastic material: broken rock, lava, bombs, fine ash, and dust

The results are 1. 2. 3. 4.

1. lower productivity 2. poorer crop quality 3. reduced agricultural income 4. ominous future

tropical rain forest

1. millions of acres are cleared for agriculture and logging 2. this results in soil degredation, loss of biodiversity, and climate change

Where does magma come from? 1. 2. 3.

1. most comes from Earth's uppermost mantle 2. greatest quantities are produced at divergent plate boundaries, in association with seafloor spreading, with lesser amounts forming at subduction zones, where oceanic lithosphere descends into the mantle 3. magma can be generated when crustal rocks are heated sufficiently to melt

What are the long term consequences of bauxite mining?

1. occur in environmentally sensitive areas of the tropics 2. mining is preceded by the removal of tropical vegetation 3.thin layer of organic matter is also disturbed 4. when the soil dries out in the hot sun, it becomes bricklike and loses its moisture-retaining qualitites 5. such soil cannot be productively farmed, nor can it support significant forest growth

There are two primary sources of heat within Earth. 1. 2.

1. one is the increasing temperature that occurs as we travel deeper into Earth's interior 2. heat released to the surrounding rocks as a magma body cool

Examples of foliation 1. 2. 3. 4.

1. parallel alignment of platy minerals 2. parallel alignment of flattened mineral grains or pebbles 3. compositional banding in which the separation of dark and light minerals generates a layered appearance 4. rock cleavage where rocks can be easily split into tabular slabs

Soil is the product of the complex interplay of several factors: 1. 2. 3. 4. 5.

1. parent material 2. time 3. climate 4. plants 5. animals 6. topography

Place these phenomena related to soil erosion in the proper sequence

1. rain drop impact 2. sheet erosion 3. rills 4. gullies 5. stream

What are some uses of shale? 1. 2. 3.

1. raw material for pottery, brick, tile, and china 2. shale is mixed with limestone to make Portland cement 3. in the future, one type of shale, called oil shale, may become a valuable energy source

Heat may be transported from the mantle into the shallowest layers of the crust. 1. 2. 3.

1. rising mantle plumes 2. upwelling at mid-ocean ridges 3. magma generated by partial melting of mantle rock at subduction zones

In order of increasing particle size, common detrital sedimentary rocks include: 1. 2. 3.

1. shale 2. sandstone 3. conglomerate or breccia

Characteristic of large caldera-forming eruptions

1. slow upheaval of the floor of the caldera that produce a central elevated region called a resurgent dome 2. Unlike calderas associated with shield volcanoes or composite cones, Yellowstone-type depressions are so large and poorly defined that many remained undetected until high -quality aerial and satellite images became available.

Although we are using greater quantities of energy from alternative sources such as 1. 2. 3. 4. the U.S. Department of Energy projects that fossil fuels will continue to be very important for decades to come, providing more than 75% of U.S. energy in the year 2035.

1. solar 2. wind 3. geothermal 4. hydroelectric

The preceding discussion has shown that the origin and history of sandstone can be deduced by examining the 1. 2, 3,

1. sorting 2. roundness 3. mineral composition of its constituent grains Knowing this information allows us to infer that a well-sorted, quartz - rich sandstone consisting of highly rounded grains must be the result of a great deal of transport.

What caused the Dust Bowl?

1. strongest winds 2. expansion of agriculture during an unusually wet period that set the stage for the disastrous period of soil erosion 3. mechanization allowed the rapid transformation of the grass-covered prairies of this semiarid region into farms

What two climate factors are crucial to rate of rock weathering? 1. 2.

1. temperature 2. moisture

Climate is considered to be the most influential control of soil formation. Name the elements that exert the strongest impact. 1. 2.

1. temperature 2. precipitation

Very angular grains, on the other hand, imply 2 things: 1. 2.

1. that the material were tranported only a short distance before they were deposited 2. some other medium may have transported them ex: when glaciers move sediment, the particles are usually made more irregular by the crushing and grinding action of the ice

Name the 3 factors that influence the textures of igneous rocks. 1. 2. 3. What is the dominant factor?____

1. the rate at which molten rock cools 2. the amount of silica present 3. the amount of dissolved gases in the magma rate of cooling tends to be the dominant factor

The nature of the parent material influences soils in two ways. 1. 2.

1. the type of parent material will affect the rate of weathering and thus the rate of soil formation Because unconsolidated deposits are already partly weathered, soil development on such material will likely progress more rapidly than when bedrock is the parent material 2. The chemical makeup of the parent material will affect the soil's fertility. This influences the character of the natural vegetation the soil can support.

Thus, as with other sedimentary rocks, conglomerates and breccias contain clues to their history. 1. 2.

1. their particle sizes reveal the strength of the currents that transported them 2. degree of rounding indicates how far the particles traveled 3. the fragments within a sample identify the source rocks that supplied them.

Mount Saint Helens

1. trees within a 400 km area lay intertwined and flattened 2. mudflows carried ash, trees, and water and saturated rocks debris 29 kilometers down the Toutle River 3. 59 dead 4. some suffocated from cloud of ash and gases 5.

Give examples of structures consisting of igneous rocks.

1. volcanoes ex: Mt. Rainier 2. Sierra Nevada 3. Black Hills 4. high peaks of Adirondacks 5. stones for monuments and household countertops

potassium feldspar

In addition to formation of clay minerals, some silica is removed from the feldspar structure and carried away by groundwater. This dissolved silica precipitates to produce nodules of chert or flint or it fills in the pore spaces between sediment grains, or it is carried to the ocean, where microscopic animals remove it from the water to build hard silica shells

Overview of these processes provides a useful perspective

1. weathering begins the process -physical and chemical disintegration of preexisting igneous, metamorphic, and sedimentary rocks -generates a variety of products, including various solid particles and ions in solution; these are the raw materials for sedimentary rock 2. soluble constituents are carried away by runoff and groundwater. -solid particles are frequently moved downslope by gravity, a process termed mass wasting before running water, groundwater, wind, and glacial ice remove them -transportation moves these materials from the sites where they originate to locations where they accumulate -the transport of sediments is usually intermittent. example: during a flood, a rapidly moving river moves large quantities of sand and gravel. as the floodwaters recede, particles are deposited, only to be moved again by a subsequent flood

In June 1944, a clinker aa flow ______________ meters thick moved over much of the village of ________________________________, leaving only the church steeple exposed.

10 meters or 30 feet thick San Juan Parangaricutiro

These flows destroyed nearly ____homes, covered a major roadway, and eventually reached the ______.

100 rural homes sea

Temperature increases from surface conditions to about _____C or 1800 F is displayed along the top, and pressure is shown along the vertical axis.

1000 C

Per capita consumption of nonfuel resources in the United States is nearly ___ metric tons, of which more than ___ percent are nonmetallics

11 94 %

How many orders?

12

In the first day, the cone grew to __________ feet and by the fifth day it was more than 330 feet high.

130

______% carbon dioxide

15%

The longest and largest rift eruption ever recorded on Kilauea began in ______ and continues to this day.

1983

Basaltic magma crystallizes over a range of at least ___________ of cooling about 1200 to 1000C

200

Minerals are composed of a mixture of minerals, and therefore, tend to melt over a temperature range of at least ________________ C

200

Mt. Etna in Italy has more than _____ secondary vents, some of which have built parasitic cones.

200

Paricutin is located about ______ miles west of Mexico City.

200 miles

As a result of this short life span, cinder cones are small, usually between 100 feet and 1000 feet. A few rare examples exceed ______________ feet in height.

2100.

Intermediate rocks contain at least _______ % dark silicate minerals, mainly 1. 2. 3. 4.

25% 1. amphibole 2. pyroxene 3. biotite mica 4. plagioclase feldspar

Nearly all of St. Pierre's __________________ inhabitants were killed. Only ___person on the outskirts of town --a prisoner protected in a dungeon and a few people on _______________ in the harbor were spared.

28,000 1 ships

1902 eruption of Mount Pelee' killed

28,000 people wiping out the entire population of nearby city of Saint Pierre

salt dome

In the gulf coastal plain region of the united states, important accumulations of oil occur in association with salt domes. Such areas have thick accumulations of sedimentary strata, including layers of rock salt. salt concurring at great depths have been forced to rise in columns by the pressure of overlying beds. these rising salt columns gradually deform the overlying strata. Because oil and gas migrate to the highest level possible, they accumulate in the upturned sandstone beds adjacent to the salt column

Shale, Mudstone, or Siltstone

It is common to apply the term shale to all fine-grained sedimentary rock, especially in a nontechnical context

In summary 1. Carbon moves among all ____ of Earth's major spheres 2. it is essential to every living thing in the biosphere. 3. In the atmosphere, carbon dioxide is an important greenhouse gas. 4. In the hydrosphere, carbon dioxide is dissolved in lakes, rivers, and the ocean. 5. In the geosphere, carbon is contained in carbonate sediments and sedimentary rocks and is stored as organic matter dispersed through sedimentary rocks and as deposits of coal and petroleum.

4

__________% nitrogen

5%

More than ______ eruptions have been witnessed here since 1823

50

Magmas that produce mafic rocks such as basalt contain _____ silica

50 %

Intermediate rock types, like andesite and diorite produce magma with ____ silica

60 %

The greatest volume of magma (____%) is produced along the oceanic ridge system in association with seafloor spreading.

60 %

Together, petroleum and natural gas provide more than __% of the energy consumed in the United States.

60%

Magmas that produce felsic: granite and its extrusive equivalent, rhyolite contains more than _____ silica

70 %

_______%water vapor

70%

After __________________ years of intermittent pyroclastic explosions and nearly continuous discharge of lava from its vents at its base, the activity ceased almost as quickly as it had begun.

9

500 million people from ___________ and ____________ to Italy and oregon live near active volcanoes. They face a number of volcanic hazards, such as pyroclastic flows, lahars, lava flows, falling volcanic ash, and volcanic gases.

Japan and Indonesia

bombs 6 meters and weighing 200 tons were blows 600 meters from the vent during an eruption of the ____ ___ ____

Japanese volcano Asama

Eruptions that involve very fluid basaltic lavas, such as the eruptions of _____________-- on Hawaii's Big Island, are often triggered by the arrival of a new batch of molten rock into a near - surface magma chamber.

Kilauea

Some magmas become enriched in iron or copper. At _________________, Sweden, magma composed of over 60 percent magnetite solidified to produce one of the largest iron deposits in the world.

Kirava, Sweden

Composite cones are ______________, nearly symmetrical structures consisting of alternating layers of explosively erupted ___________________ and ______________ interbedded with lava flows.

Large Cinders and ash

As the thick lava is squeezed out of a vent, it often produces a dome-shaped mass called a ___ __.

Lava dome

burial metamorphism

Low grade metamorphic conditions may be reached within the deepest layers. confining pressure and heat drive the recrystallization of the constituent minerals, changing the texture and/or mineralogy of the rock WITHOUT deformation.

It is thought that most intraplate volcanism occurs where a mass of hotter than normal mantle material called a ___________ _____

Mantle plume assends toward the surface.

After sufficient quantity of the rock has melted, blobs of buoyant magma slowly __________ __________.

Migrate upward.

layers of chromite, interbedded with other heavy minerals, are mined at ___________________ Stillwater Complex,

Montana's Sillwater Complex

Equivalent source of diamonds in US is located near

Murfreesboro, Arkansas is exhausted and serves as tourist attraction

Feldspar masses the sizes of houses have been quarried from a pegmatite in ___ Feldspar is used in the production of _____________

North Carolina ceramics

Some shield volcanoes form on continental crust 1. 2.

Nyamuragira, Africa most active volcano Newberry Volcano, Oregon

Over time, the cooler outer layer of the dome may start to crumble, producing relatively small pyroclastic flows consisting of dense blocks of lava.

Occasionally, the rapid removal of the outer layer causes a significant decrease in pressure on the hot gaseous magma in the interior of the dome.

Giganic hexagonal crystals of muscovite measuring a few meters across have been found in ____ Muscovite is used for _________________ insulation and _________________

Ontario, Canada electrical insulation and glitter

The Ring of fire, a belt of explosive volcanoes, surrounds the ___ basin.

Pacific

Most are located in a relatively narrow zone that rims the Pacific Ocean, called the ___ _____ ___.

Ring of Fire

These plumes of solid yet mobile rock _______toward the surface in a manner similar to the blobs that form within a lava lamp.

Rise

Although the main pyroclastic flow was largely confined to the valley of ___________________ Blanche, a low-density fiery __________________ spread south of the river and quickly engulfed the entire city.

Riviere Blanche surge

As this water evaporates, ___ crystals form. As these crystals gradually grow larger, they weaken the rock by pushing apart the surrounding grains or enlarging tiny cracks.

Salt

Another expansive force that can split rocks is created by the growth of ___ ____.

Salt crystals

When a rock undergoes mechanical weathering, it is broken into ____ and ____ pieces, each retaining the characteristics of the original material.

Smaller and smaller

The coarse particles in a conglomerate may reflect the action of energetic mountain streams or result from strong wave activity along a rapidly eroding coast.

Some glacial and landslide deposits also contain plentiful gravel

calderas

Some volcanoes have very large circular depressions called _____ that have diameters greater than .6 miles and in some cases exceed 30 miles

Poorly drained and waterlogged soils found in bottom-lands have a much different character.

Such soils are thick and dark. The dark color results from the large quantity of organic matter that accumulates because saturated conditions retard the decay of vegetation.

Breaking a rock into smaller pieces increases the ______________ __________available for chemical attack.

Surface area

By breaking rocks into smaller pieces, mechanical weathering increases the amount of ____ ____ available for chemical weathering.

Surface area

The capital city, Plymouth, was destroyed and ___________ of the population that evacuated.

Two-thirds

Plant roots in search of nutrients and water grow into fractures, and as the roots grow, they ____ apart the rock

Wedge

clearing of rain forest

accelerates soil erosion when vegetation si there, roots anchor the soil and leaves and branches provide a canopy that protects the ground by deflecting the full force of the frequent heavy rains when the protective vegetation is gone, soil erosion increases

Thin blanket of

air

bituminous coal is metamorphosed into

anthracite, a very hard, shiny black metamorphic rock anthracite is a clean burning fuel, only a relatively small amount is mined. anthracite is not widespread and is more difficult and expensive to extract than the flat-lying layers of bituminous coal

For two weeks prior to the first eruption, numerous Earth tremors caused ___________________ in the nearby village of _____________.

apprehension Paricutin

Cinder cones

are built from ejected fragments that begin to harden in flight to produce the vesicular rock scoria

The gas-laden magmas that migrate through pipes travel rapidly enough to undergo minimal alteration during their _______.

ascent

When magmas with intermediate (andesitic) or felsic (rhyolitic) compositions erupt explosively, they emit ______________ and the vesicular rock ________________.

ash pumice

The pyroclastic fragments range in size from fine ________ to _________________ that may exceed 3 meters in diameter.

ash to bombs

Andesitic magmas can also form when rising basaltic magmas ______________________ crustal rocks that tend to be ___________ rich.

assimilate silica

Eruption colums can rise 25 miles into the ________________.

atmosphere

Vast majority of lava of Earth is _________ in composition. 90%

basaltic

The hot __________________ magma may heat the overlying crustal rocks sufficiently to generate a secondary, silica - rich magma. If these low-density silica rich magmas reach the surface, they tend to produce ___________________ eruptions that we associate with convergent boundaries.

basaltic explosive

How can we detect this event?

because the summit of the volcano begins to inflate and rise months or even years before an eruption

Why are shales considered weak?

because they are poorly cemented and therefore not well lithified

Parent material can either be the overlying ___ or a layer of ____ deposits.

bedrock unconsolidated deposits

One product of this chemical weathering of solid rock is the soluble _____________ ion

bicarbonate ion, which is carried by groundwater and streams to the ocean.

Like coal, petroleum and natural gas are ___ ___ derived from the remains of organisms. However, the environments in which they form are different as are the organisms.

biological products

The parent rocks of most marbles contain impurities that color the stone Thus marble can be pink, gray, green or ___ and may contain accessory minerals such as chlorite, mica, garnet, and wollastonite

black

These hot, metal-rich fluids eventually rise along fractures and gush from the seafloor at temperatures of about 360 F, generating particle filled clouds called ___ ___.

black smokers

particles larger than 64 millimeters in diameter are called ______________ when they are made of hardened lava

blocks

Melting of these _______________ , a process called ______________________________, changes the overall composition of the magma body.

blocks assimilation

Each drop acts like a tiny __, blasting movable soil particles out of their positions in the soil mass. Then, water flowing across the surface carries away the dislodged soil particles. Because the soil is moved by thin sheets of water, this process is termed ___ ____.

bomb sheet erosion

Because large particles abrade and become rounded very rapidly during transport, the pebbles and cobbles in a _____indicate that they did not travel far from their source before they deposited.

breccia

As magma rises, the confining pressure is reduced, causing the dissolved gases to separate from the melt to form tiny __________.

bubbles

How are detrital sedimentary rocks distinguished?

by particle size

Most common cements are 1. 2. 3.

calcite = will effervesce with dilute HCl silica= hardest cement, produces hardest sedimentary rocks iron oxide= an orange or dark-red color indicates this

Further cooling generates _____________________ rich plagiochase feldspar as as well _________________.

calcium - rich pyroxene

Water - dewelling organisms extract this dissolved material to produce hard parts of ____________ __________.

calcium carbonate.

gypsum

calcium sulfate CaSO4 2H20 main ingredient in rock gypsum basic ingredient in plaster of Paris used in wallboard and interior plaster

Calderas

caldaria = cooking pot large steep-sided depressins with diameters that exceed .6 miles and have a circular form those less than 1 kilometer across are called collapse pits or craters

A _______________________ usually forms when the roof of solid rock above a magma chamber collapses.

caldera

Another feature to many active shield volcanoes is a large , steep - walled ________________________, that occupies the summit.

caldera

Soils

can be improved through fertilization and irrigation but can be destroyed through careless activities

Diamonds are thought to originate at depths of nearly 200 km, where the confining pressure is great enough to generate this high-pressure form of

carbon

As is the case with other fossil fuels are burned, the combusion of coal produces

carbon dioxide

The injection of a fresh supply of hot molten rock heats and remobilizes the semi-fluid magma ________________.

chamber

In the most extreme environments, even the highest-grade metamorphic rocks undergo ____.

change

during the crystallization process, the composition of the remaining liquid of the magma also continually ____________________.

changes

Natural rates of erosion vary greatly from one place to another and depend on soil ________ as well as factors such as ___, ____, and type of vegetation.

characteristics climate slope type of vegetation

The types of and abundance of organisms present have a strong influence on the physical and ____ properties of a soil.

chemical

Many rock outcrops have a rounded appearance. This occurs because ______ weathering works inward from exposed surfaces. Fig. 6.10 shows how angular masses of jointed rocks change through time. This process is called ____________ _____________

chemical spheroidal weathering

Lesser amounts of ______

chlorine, hydrogen and argon

An idealized transition in mineralogy that results from the regional metamorphism of shale is shown in figure 8.25 First new minerals to form as shale changes to slate is _____

chlorite

The mineral ____ begins to form when temperatures are relatively low, less than 400 F. Thus rocks that contain chlorite (usually slates) are ___ ___.

chlorite low-grade

This process begins when compressional stress begins to deform rock units, producing broad folds. With further deformation, the clay minerals in shale, which initially aligned roughly parallel to the bedding surfaces, begin to recrystallize into tiny flakes of _____ and _____.

chlorite and mica

This type of magmatic segregation serves to concentrate selected metals, producing major deposits of ________________ ore of chromium, magnetite and ________________.

chromite magnetite and platinum

Some chemical sedimentary rocks exhibit this __ texture also.

clastic ex: coquina, the limestone composed of shells and shell fragments, is clastic ex: oolitic limestone

Other important factors examined here include the roles of rock characteristics and _____.

climate

Some of these eruptions may have an impact on Earth's ________________.

climate

Dolostone

closely related to limestone is dolostone, a rock composed of the calcium - magnesium carbonate mineral

Air pollution in another significant problem associated with the burning of ___.

coal

In addition to oil and natural gas, ____ is commonly called a fossil fuel.

coal

The third category is organic sedimentary rock, which form from the carbon-rich remains of organisms. ex: _____ The black combustible rock consists of organic carbon from the remains of plants that died and accumulated on the floor of a swamp. The bits and pieces of undecayed plant material that constitute the "sediments" in coal are quite unlike the weathering products that up detrital and chemical sedimentary rocks

coal

In some cases, a very dense form of quartz called ________ and minute ________________ are found.

coesite diamonds

A conical shape with a steep summit area and gradually sloping flanks is typical of most large __________________________ cones.

composite

When a volcano becomes inactive, congealed magma often becomes preserved in the feeding _______________ of the volcano as a crudely cylindrical mass.

conduit

Most volcanic eruptions are fed lava through __________ that connect shallow magma chambers to vents located at the surface.

conduits

Silicate minerals make up most of Earth's ___ and that these minerals are composed of only ___ elements.

crust 8

Heat from the hot magma is often sufficient to partially melt the overlying _____________ rocks, generating a less dense, silica rich magma, which continues the journey toward's Earth's surface.

crustal

rain forest soils

develop under conditions of high temperatures and rainfall, they are severly leached leaching removes soluble calcium carbonate removes silica insoluble oxides of iron and aluminum become concentrated in the soil iron oxide gives soil its distinctive color bacterial action is high, so there is little humus leaching destroys fertility because most plant nutrients are removed by the large volume of downward-percolating water soil contains few available nutrients

Another economically important mineral with an igneous origin is ________________.

diamond

These ________________ are clearly related to variations in the degree of ___________________ experienced in each metamorphic zone.

differences metamorphism

Slope orientation

direction a slope is facing, is another consider the difference in the amount of solar radiation received causes differences in soil temperature and moisture, which in turn influence the nature of the vegetation and the character of the soil

Regional and subduction metamorphism involve ____ stress.

directional

Another important type of accumulation generated by hydrothermal activity is called a ______________________________ deposit.

disseminated deposit

carbon dioxide

dissolved in water forms carbonic acid, the same weak acid produced when soft drinks are carbonated

Marble headstone composed of calcite or calcium carbonate, readily ___________________ in a weakly ___________________ solution.

dissolves acidic

In some metamorphic environments, hot fluids transport mineral matter over considerable ___. This occurs, when hot, iron-rich fluids are expelled from a magma body as it cools and solidifies.

distances

Much of Earth's volcanic activity occurs along oceanic ridges or _______________- boundaries

divergent

This process is responsible for generating magma along -________plate boundaries (oceanic ridges) where plates are rifting apart.

divergent

Coal, petroleum, and natural gas are the primary fuels of our modern industrial _______

economy.

Eventually, some of the fuels are recovered and burned to generate ____ and ___ our transportation system

electricity fuel

petrified wood

example of chert is chert made when silica-rich material such as volcanic ash buries trees. groundwater rich in silica from the ash penetrates the wood as the dissolved silica precipitates, it gradually replaces the wood shape and structures such as growth rings are preserved

Composite cones are noted for generating _______________________ eruptions that eject huge pyroclastic material.

explosive

Gases also give magmas their ________________ character.

explosive

Different parts of each layer possess a distinctive set of characteristics that reflect the conditions in a particular environment. To describe such sets of sediments the term ____ is used.

facies

Steepness of slop is an important factor in soil erosion. The steeper the slope, the ____ the water runs off and the greater the erosion.

faster

When granite weathers, the ____ crystals dull and slowly turn to clay, releasing the once interlocked quartz grains, which still retain their fresh, glassy appearance.

feldspar

other common minerals in detrital rocks are 1. 2.

feldspars and micas Because chemical weathering rapidly transforms these minerals into new substances, their presence in sedimentary rocks indicates that erosion and deposition were fast enough to preserve some of the primary minerals from the source rock before they could be decomposed

partial melting of intermediate rocks yields __________________ or ____________ magmas

felsic or granitic

These materials are important because they are sources of specific chemical elements or compounds. Such minerals are used in the manufacture of chemicals and the productin of

fertilizers

Through the study of metamorphic rocks in their natural settings called ____ ____ and through the experimental studies, researchers have learned that certain minerals, such as those in figure 8.25 are good indicators of the metamorphic environment in which they formed.

field studies

Although most dislodged soil particles move only a short distance during each rainfall, substantial quantities eventually leave the ___ and make their way down slope to a ____.

fields stream

As large slabs of rock move in opposite directions, the minerals in the fault zone between them tend to form elongated grains that give the rock a _______ and/or lineated appearance. Rocks formed in these zones of intense ductile deformation are termed _______________________.

foliated mylonite mylo = a mill ite = a stone

A rock that exhibits a preferred orientation of its mineral constituents is said to possess ______.

foliation

Metamorphic rocks are classified by the type of ___ exhibited and, to a lesser extent, the chemical composition of the parent rock.

foliation

Uses of soils

food fiber other basic materials

Every time it rains, raindrops strike the land with surprising ___.

force

Volcanic activity frequently begins when a fissue (crack) develops in Earth's crust, as magma moves ____________ up through a fissue, its path is usually localized into a circular _______________ that terminates at a surface opening called a ________________.

forcefully conduit vent

Detrital rocks

form from the solid products of weathering

pillow lavas

form on the ocean floor and have elongated shapes, resembling toothpaste coming out of a tube

Kilauea's caldera

formed by gradual subsidence as magma slowly drained laterally from the underlying magma chamber, leaving the summit unsupported

Under the right conditions, some of these carbon - rich deposits are converted to _____ ______.

fossil fuels such as coal, petroleum, or natural gas

At the other extreme, highly viscous magmas expel particles of ____________________ lava and gases at supersonic speeds, creating buoyant plumes called _________________ _______________.

fragmented lava eruption columns

Many of these vents emit only gases and are called _______________.

fumaroles

________________ is the intrusive equivalent of basalt. Intrusive means coarse or large grained. Like basalt, it tends to be dark green to black in color and composed primarily of ___________________ and ______________- ______________ plagioclase feldspar. Gabbro is uncommon in the continental crust, it makes up a significant percentage of ________________ __________________

gabbro pyroxene calcium - rich oceanic crust

During recrystallization, certain metamorphic minerals, such as ____, tend to develop a small number of very large crystals.

garnet

Near the magma body, higher-temperature minerals such as _____may form, whereas farther away, low grade minerals such as chlorite are formed

garnet

Under more extreme conditions , metamorphic rocks may contain ______ and ____ crystals

garnet staurolite

Like schists, gnesses may also include larger crystals of accessory minerals such as _____ and _______.

garnet and staurolite

Then, on February 20, sulfurous _________ began billowing from a small depression that had been in the cornfield for as long as local residents could remember.

gases

When fluid basaltic magma erupt, the pressurized _____________ readily escape.

gases

Hawaii's Kilauea Volcano

generated relatively quiet outpourings of fluid lavas gentle eruptions are not without some fiery displays. fountains of incandescent lava sprays hundreds of meters in the air most recent active phase began in 1983 180 homes destroyed national park visitor center destroyed

Soil erosion by water also occurs on _____ slopes.

gentle

Soil forms where the 1. 2. 3. 4. meet

geosphere atmosphere hydrosphere biosphere

As shown in figure 4.17, when a typical geothermal gradient is compared to the melting point curve for the mantle rock peridotite, the temperature at which peridotite melts is higher than the _____________________ gradient. Thus, under normal conditions, the mantle is _____________________. However, tectonic processes trigger melting through various processes, including ________________ the melting point (temperature) of mantle rock.

geothermal solid reducing

Obsidian flows, typically few hundred feet thick, provide evidence that rapid cooling is not the only mechanism that produces a ____________________ texture. Magmas with a high ___________ content tend to form long, chain-like structures (polymers) before crystallization is complete. These structures, in turn, impede ionic transport and increase the magma's viscosity. _______________ is a measure of a fluid's resistance to flow.

glassy silica viscosity

Some volcanic structures that appear to be somewhat randomly distributed around the __.

globe

Gneiss represents the highest-grade metamorphic rock in the sequence of shale, slate, phylolite, schist, and ____

gneiss

Under more intense conditions, a _____ texture that exhibits layers of ______ and _____ minerals may develop.

gneistic texture dark and light

It varies from low grade to high ____.

grade

One conservation method in which crops are planted parallel to the contours of the slope. This pattern reduces soil loss by slowing runoff. Strips of ___________________ or cover crops such as hay slow runoff even more and act to promote water _______________________ and sediment.

grass infiltration

Pyroclastic flows are propelled by the force of _______________________- and tend to move in a manner similar to snow avalanches

gravity

Still deeper cuts in the soil, known as _____are created as rills enlarge.

gullies

aa

have surfaces of rough, jagged blocks with dangerously sharp edges and spiny projections aa lavas cannot change to pahoehoe

The most important factor driving metamorphism is ____ because it provides the energy needed to drive the chemical reactions that result in the recrystallization of existing minerals.

heat

Most gneisses are generated through ____ grade metamorphism of shale

high

high grade

high temperatures and pressures

formation of lignite and bituminous coal

higher temperatures bring about chemical reactions within the plant material and yield water and organic gases (volatiles) water and volatiles are pressed out and the proportion of fixed carbon increases the greater the carbon content, the greater the coal's energy ranking as a fuel lignite turns into bituminous coal

3. Yellowstone - Type Calderas

historic and destructive eruptions such as Mount St. Helens and Vesuvius pale in comparison what happened 630,000 years ago in the region now occupied by Yellowstone National Park 240 cubic miles of pyroclastic material erupted. catastrophic eruption sent showers of ash as far as the Gulf of Mexico and resulted in the formation of a caldera (43 miles across) vestiges of this event are the many hot springs and geysers in the Yellowstone region

In 1991, a hot ash cloud from Japan's Unzen Volcano engulfed and burned hundreds of ______________ and moved cars ___________________________ feet.

homes 250 feet

These vertical differences, which usually become more pronounced as time passes, divide the soil into zones or layers known as ______.

horizons

Sometimes sediments do not accumulate in horizontal beds. When a bed of sedimentary rock is examined, we see layers within it that are inclined to the _________________. This is called ____ ____, and it is most characteristic of sand dunes, river deltas, and certain stream channel deposits

horizontal cross-bedding

Along convergent plate boundaries, the greatest differential stress is directed ____ in the direction of plate motion. Consequently, in these settings, the crust is greatly shortened (horizontally) and thickened (vertically) resulting in ____ topography.

horizontally mountainous

over the next 3 years, the general eruptive patterns consisted of short periods __________ to ______________ when fountains of gas-rich lava sprayed skyward.

hours to days

These large volume eruptions account for the majority of _________________ _________________

human fatalities

When rock has been blasted in search of minerals or for road construction, the impact of ____is particularly noticeable.

humans

About one-half of the total volume of good quality surface soil is a mixture of disintegrated and decomposed rock (mineral matter) and _____ , the decayed remains of animal and plant life (organic matter).

humus

The end product is ___, a material that no longer resembles the plants and animals from which it is formed.

humus

Among the best known and most important ore deposits are those generated from hot, iron-rich fluids called _______________________ (hot-water) solutions.

hydrothermal

Many of the most productive deposits of gold, silver, and mercury occur as ________________________ vein deposits

hydrothermal

If complete melting occurs, the rock has entered the realm of _____________ activity.

igneous

Most pegmatites are located within large ______________________ masses or as dikes or veins that cut into the host rock that surrounds the magma chamber.

igneous

gold, silver, copper, mercury, lead, platinum, and nickel are produced by ___________________- processes.

igneous

What two types of parent rocks make up most of Earth's crust and mantle?

igneous and metamorphic rocks

magma is completely or partly molten rock, which when cooled solidifies to form ________________ ______________ composed of __________minerals.

igneous rock silicate minerals

Fig. 4.2

igneous rock composed of interlocking crystals (picture of a granite rock)

laccoliths

igneous rock forcibly injected between sedimentary strata, so as to arch the beds above while leaving the beds relatively flat.

most of the solid Earth consists of 1. 2.

igneous rocks metamorphic rocks

Sedimentary rocks

illustrate the portion of the rock cycle that occurs near Earth's surface--the part that pertains to sediments and sedimentary rocks

A horizon

image

Bowen Reaction series

image

C horizon

image

Crater Lake, Oregon

image

Dust Bowl

image

E horizon

image

Granite

image

Half dome in Yosemite National Park

image

Kilauea caldera

image

Mount Pelee'

image

Mt. Etna in Italy

image

O horizon

image

Plants and Animals in soil formation

image

Stone Mountain, Georgia

image

The Destruction of Pompeii

image

White Chalk Cliffs

image

Wizard Island

image

Yellowstone - type calderas

image

acid rain

image

andesite

image

biotite

image

bituminous coal

image

blocks volcano

image

bombs in volcano

image

coal

image

coesite

image

cross bedding

image

dark ferromagnesian silicates

image

detrital sedimentary rock

image

fissility

image

flint

image

foliation

image

fumaroles

image

garnet

image

geysers

image

glassy texture

image

gneiss

image

good drainage soil

image

gullies

image

hornfels

image

hot springs

image

humus

image

impact metamorphism

image

joints in rocks

image

leaching

image

quartz (SiO2) sandstone

image is the parent of quartzite

arkose

image when sandstone contains appreciable quantities of feldspar (25% or more) also contains quartz and bits of mica mineral composition of arkose indicates that the grains were derived from granitic source rocks particles are poorly sorted and angular, which means short distance transport, mineral chemical weathering in a relatively dry climate and rapid deposition and burial

coast of Wales

image 7.1

Taj Mahal

image of building made of marble

carbon organic compounds

image of glucose is the building block of life, as it readily combines with hydrocarbons and oxygen to form the fundamental organic compounds that compose living things.

rust

image of iron oxide

Lincoln Memorial

image of marble building

All magma contain some water vapor and other gases that are kept in solution by the ___________________________ pressure of the overlying rock.

immense

Many of the differences exist because the length and steepness of slopes have a significant _______________on the amount of erosion and the water content of soil.

impact

Consequently, the chemical makeup of an igneous rock can be ____________ directly from the _____________ content.

inferred silica

Accumulation of plant remains

initial stage in coal formation is the accumulation of large quantities of plant remains must have a swamp environment plants are attacked by bacteria and partly decompose the organic material and liberate the oxygen and hydrogen as these elements escape, carbon gradually increases bacteria cannot finish decomposing because their growth is impeded by acids liberated by plants

fig. 4.3

intrusive versus extrusive rocks smart figure (listen to it)

Some gneisses will split along the layers of platy minerals, but most break in

irregular fashion

diagenesis

is a collective term for all the chemical, physical, and biological changes that take place after sediments are deposits and during and after lithification dia = change genesis = origin

Soil

is a combination of mineral and organic matter, water, and air--the portion of the regolith that supports the growth of plants

weathering

is a key process in the formation of soil

quartz

is abundant because it is extremely durable and very resistant to chemical weathering when igneous rocks such as granite are attacked by weathering processes, individual quartz grains are freed

C horizon

is characterized by partially altered parent material whereas O, A, E, and B horizons bear little resemblance to the parent material, it is easily identifiable in the C horizon. Although this material is undergoing changes that will eventually transform it into soil, it has not yet crossed the threshold that separates regolith from soil

soil

is dynamic and sensitive to almost every aspect of its surroundings

Coastal batholith of Peru

is even thinner essentially a flat slab with an average thickness of only 2 to 3 kilometer

limestone

is made from calcite

Coal

is made of organic matter end product of large amounts of plant material, buried for millions of years

Soil

is material that develops in response to complex environmental interactions among different parts of the Earth system.

chert

is silica rich

Diorite

is the intrusive equivalent of andesite. coarse grained rock that looks like gray granite.

quartz

is the main mineral in most sandstones such rock is often called quartz sandstone

water

is the most important agent of chemical weathering

scoria

is the name applied to vesicular ejecta that is a product of basaltic magma These black to reddish brown fragments are generally found in the size range of lapilli and resemble cinders and clinkers produced by furnaces used to smelt iron.

metamorphism

is the transformation of one rock type into another rock type

Why is carbon dioxide important?

it is a greenhouse gas, which means it is an efficient absorber of energy emitted by Earth and thus influences the heating of the atmosphere.

The loss of fertile topsoil may not be obvious to the untrained eye,

it is a significant and growing problem as human activities expand and disturb more and more of Earth's surface

Soil erosion is a natural process; ___

it is part of the constant recycling of Earth materials that we call the rock cycle.

Sediment has two principle sources 1. 2.

it may be an accumulation of material that originates and is transported as solid particles derived from both mechanical and chemical weathering deposits of this type are termed detrital and the sedimentary rocks that they form are called detrital sedimentary rock

Fractures produced by these activities generally form a definite pattern and are called ____.

joints

Many physical features, such as ______ can be important because they influence the ability of water to penetrate rock

joints

In addition to violent eruptions, large composite cones may generate a type of fluid mudflow referred to by its Indonesian name, ________________.

lahar

As silt and clay accumulate, they tend to form thin layers, which are commonly referred to as ____.

laminae lamin = thin sheet

Why did erosion occur at slower rate in the past?

land surface was covered and protected by trees, shrubs, grasses, and other plants

In continental settings, the density of crustal rocks is ____________- than that of the ascending material, causing the __________ to pond at the crust-mantle boundary.

less magma

When the partially melted rock cools the ____ bands will be composed of _____ or ____-appearing components, while the dark bands will consist of unmelted ______ material.

light igneous or igneous -appearing metamorphic

Igneous rocks and the magmas from which they form can be divided into broad groups according to their proportions of ______ and -_________ minerals.

light and dark

Because marble and the common sedimentary rock limestone have the same mineralogy (calcite), it seems reasonable to conclude that ____ is the parent rock of marble.

limestone

crater

located at the summit of most volcanic cones is a somewhat funnel-shaped depression

most nutrients that support the rain forest are

locked up in the trees themselves as vegetaion dies and decomposes, the roots of the rain forest trees quickly absorb the nutrients before they are leached from the soil when trees are removed for farming or for timber, most of the nutrients are removed as well what remains is a soil that contains little to nourish planted crops

Cinder cones are composed mostly of ______ scoria fragments, some produce extensive lava fields.

loose

Because slate typically forms during the ___ - grade metamorphism of shale, evidence of the original sedimentary bedding planes is often preserved.

low

Basaltic magmas are _____in silica and are generally more ______________. Basaltic magmas also erupt at higher temperatures than granitic magmas --usually at temperatures between _______________ and _______________.

low fluid 1050 and 1250 Celsius or 1920F and 2280F

In addition to textural changes, we encounter corresponding changes in mineralogy as we shift from regions of ___-grade metamorphism to regions of ___grade metamorphism.

low high

Silica content ranges from a ___________ of about 40 percent in _____________ rocks to a high of more than _______________ percent in _____________ rocks.

low ultramafic 70% felsic

Carbonaceous shale is a sign of a ___ energy, organic-rich environment, such as a swamp or lagoon.

low - energy

Notice that hydrothermal metamorphism occurs in relatively ____ temperature and ____ pressure environments,

low temperatures low pressure

low grade

low temperatures and pressures

Burial and subduction metamorphism occur under relatively _____ temperature and _________pressure conditions.

low- temperature and high-pressure

Decompression meling occurs where hot, solid mantle rock ascends in zones of convective upwelling, thereby moving into regions of _____ pressure.

lower

As rock begins to melt, the minerals with the ______________ melting temperatures are the first to melt.

lowest

The gaseous components in magma, mainly dissolved water, also affect the mobility of ________________

magma

The majority of hydrothermal deposits originate from hot, metal-rich fluids that are remnants of late-stage magmatic processes. During solidification, liquids plus various metallic ions accumulate near the top of the ___________________ chamber.

magma

One way andesitic magma can form is when a rising mantle-derived basaltic magma undergoes ___________________ ________________ as it slowly makes its way through the continental crust.

magmatic differentiation

the formation of one or more secondary magmas from a parent magma is called

magmatic differentiation

Magmatic segregation is important in the late stages of the ______________________ process.

magmatic process

Along certain convergent plate boundaries, two plates move toward each other, and a slab of oceanic lithosphere descends into the ____, generating a _______________________.

mantle deep - ocean trench

And, limestone is metamorphosed to produce

marble

differential weathering

masses of rock do not weather uniformly

Although Pure water is nonreactive, a small amount of dissolved ______________ is generally all that is needed to activate it.

material

Although supplies are generally plentiful, most industrial minerals are not nearly as abundant as building ___

materials.

Chemical weathering contributes to __________________ weathering also. It does so by weakening the outer portions of some rocks, which in turn, makes them more susceptible to being broken by mechanical weathering processes.

mechanical

What are some factors that influence the rate of rock weathering? 1.

mechanical weathering, breaks rocks into smaller pieces, the amount of surface area exposed to chemical weathering increases.

metamorphic rocks are produced from preexisting sedimentary and igneous rocks, as well as from other

metamorphic rocks

Hot, chemically active fluids enhance _____________ by dissolving and transporting ions from one site in the crystal structure to another, thereby facilitating the process of __________________.

metamorphism recrystallization

Because calcite and quartz are simple chemical compounds compared to clay minerals, their mineralogy does not change during ___.

metamorphism calcite remains calcite quartz remains quartz These minerals recrystallize to produce larger fused grains that are the main constituents of marble and quartzite, respectively.

The _________________________ changes because the rock is subjected to new conditions, usually elevated temperatures and pressures, which are significantly different from those in which it initially formed. For example, clay minerals which are the most common minerals in sedimentary rocks, are stable only at Earth's surface.

mineralogy (mineral constituents)

In areas affected by metamorphism, there are systematic variations in _____ and _____ of the rocks that can be observed.

mineralogy and texture

dikes can also radiate from an eroded volcanic ____________, like spokes on a wheel. In these situations, the active ascent of magma generated fissures in the volcanic cone out of which lava flowed.

necks

Some chemical sedimentary rocks have a ___ or crystalline texture, in which the minerals form a pattern of interlocking crystals.

nonclastic ex: rock salt, ex: rock gympsum ex: limestone

metamorphic rocks that do not exhibit foliated textures are referred to as _______.

nonfoliated.

Basaltic rocks make up the _______________ floor as well as many of the volcanic islands located within the ocean basins. Basalt also forms extensive _______flows on the continents.

ocean lava

rain dissolves some carbon dioxide as it falls through the atmosphere, and additional amounts released by decaying ____ matter are acquired as the water percolates through the soil.

organic

Certain bog soils are composed almost enirely of ___ matter, whereas desert soil might contain as little as a small fraction of ___ %

organic 1%

Plants and animals furnish ___ matter to the soil.

organic matter

___ ___ also has a high water-holding ability and thus aids water retention in a soil.

organic matter

Because many of the processes that operate on Earth involve carbon dioxide, this gas is constantly moving into and ____ of the atmosphere.

out

_____________________ dissolved in water oxidizes some material example iron nail in moist soil will develop iron oxide : coating of rust

oxygen

Others are ___________________ cones that are found on the flanks or within the calderas of larger volcanic structures.

parasitic

These ion-rich fluids can also generate _____, very coarse -grained granitic (felsic) igneous rocks.

pegmatites

Joints are important rock structures that allow water to ____ depth and start the process of weathering long before the rock is exposed.

penetrate

Another important igneous rock, ________________ contains mostly olivine and pyroxene and thus falls on the opposite side of the compositional spectrum from granitic rocks.

peridotite

Further evidence for a mantle source are inclusions of the rock __________________, which basaltic magmas often carry up to the surface from the mantle

peridotite

Gradually, it undergoes ___ and ____ changes as the processes of soil formation progress.

physical and chemical

One rare type of conduit, called a ________, carries magma that originated in the mantle at depths that may exceed 93 miles.

pipe

Usually such enrichment occurs in deposits containing ____, the most common widespread sulfide mineral. Pyrite is important because when it chemically weathers, _____ _____ forms, which enables percolating waters to dissolve the ore metals.

pyrite sulfuric acid

Powerful hot blasts that carry small amounts of ash separate from the main body of a _____________________ flow.

pyroclastic

Pyroclastic flows may originate in a variety of volcanic settings. Some occur when a powerful eruption blasts _________________ material out of the side of a volcano.

pyroclastic

near one end of the continuum are rocks composed entirely of light colored silicates :_____ and ________ ______________. Igneous rocks in which these are the dominant minerals have a ______________ composition. Geologists also refer to granitic rocks as being ______________, a term derived from (fel)dspar and (si)lica (quartz).

quartz and potassium feldspar granitic composition felsic

2. recrystallization the produces new minerals

recrystallization is the creation of new mineral grains from preexing ones. when recrystallization occurs as rock is being subjected to differential stress, any elongated mineral (such as amphiboles) and platy minerals (such as micas) that form tend to recrystallize perpendicular to the direction of maximum stress. newly formed mineral grains

Earth's land surface is covered by ______, a layer of rock and mineral fragments.

regolith

After flowing as a thin, unconfined sheet for a relatively short distance, threads of current typically develop, and tiny channels called ____ begin to form.

rills

In addition, hot ion-rich solutions facilitate the movement of mineral matter into and out of ____ bodies, thereby changing their overall chemical composition.

rock

Oftentimes, pumice and obsidian can often be found in the same ________________ mass, where they exist in alternating forms.

rock

For example, in a near-surface environment where rocks are brittle, as the magma pushes upward, it causes numerous fractures in the overlying _________________. The force of the ________________ magma is often sufficient to dislodge and incorporate the surrounding host rock.

rock injected

This most commonly occurs on the ocean floor in association with _________________________ spreading.

seafloor

Most shield volcanoes begin on the ocean floor as _________________, a few of which grow large enough to form volcanic islands

seamounts

chert nodules are sometimes referred to as

secondary cherts or replacement cherts they most often occur with beds of limestone form when silica, originally deposited in one place, dissolves, migrates, and then chemically precipitates elsewhere, replacing older material

Other energy sources such as oil, natural gas and uranium are derived from s_________ rocks.

sedimentary

Some pegmatites contain ______________- gems such as beryl, topaz, and tourmaline

semiprecious gems

lava tubes

serve as insulated pathways that facilitate the advance of lava great distances from its source, therefore lava tubes are important features of fluid lava flows

Dikes

serve as tabular conduits that transport magma

Depending mainly on the composition of the parent rock, A variety of metamorphic rock can form in the same ____.

setting

Igneous rocks form in two basic _____________. 1. Molten rock may crystallize at _________ 2. It may solidify at Earth's ___________________.

settings 1. depth 2. Earth's surface

The particles range in size from very fine dust and sand-sized volcanic ash to pieces that weigh ____________ ________________.

several tons

A _____________________-volcano is produced by the accumulation of fluid basaltic lavas and exhibit the shape of a broad, slightly domed structure that resembles a warrior's shield.

shield

Shiprock is higher than most _______________________ and one of many such landforms that protrude conspicuously from the red desert landscapes of the _______ ________.

skyscrapers American SouthWest

Shale changes to fine grained ____

slate

Unlike shale, which splits along bedding planes, ___ often splits across bedding.

slate

example of low grade common sedimentary rock shale becomes the more compact metarmorphic rock ____. this transformation clay minerals in shale are transformed into tiny chlorite and muscovite flakes.

slate

Regional metamorphism produces some of the most common metamorphic rocks. In these settings shale is metamorphosed to produce the sequences of 1. 2. 3. 4.

slate phyllite schist gneiss

In low-grade metamorphic environments, ____ cleavage is known to develop where beds of shale and related sedimentary rocks are strongly folded and metamorphosed to form slate.

slaty

Cinder cones have simple, distinct shapes determined by the ________ that loose pyroclastic material maintains as it comes to rest.

slope

The movement of silica - rich rhyolitic lava may be too _______________ to perceive.

slow

Dikes weather more _____________________ than the surrounding rock. Dikes tend to have a wall like appearance.

slowly

highly insoluble clay minerals are very ____ removed by subsurface water

slowly

Other less-common types of metamorphism generate relatively _____ amounts of metamorphic rock that tends to be geographically ___________.

small localized

Once weathering and other processes create ____, plants carry the intermediary role of assimilating the necessary elements and making them available to animals, including humans.

soil

When Earth is viewed as a system, ____ is referred to as an interface--a common boundary where different parts of a system interact.

soil

Without the stabilizing effects of plants, the ____ is more easily swept away by the wind or carried downslope by sheet wash.

soil

If you were to dig a trench in soil, you would see that its walls are layered. Such a vertical section through all of the soil horizons constitutes the ________ ______

soil profile

Astronomers are so certain the Mauna Kea is over the hill that they built an elaborate observatory on its ______________, housing expensive teloscopes.

summit

Craters also form when the ______________ area of a volcano collapses following an eruption.

summit

vent in volcano

surface opening

Burial metamorphism

tends to occur where massive amounts of sedimentary or volcanic material accumulate in a subsiding basin such as Gulf of Mexico.

pyroclastic materials are also called _________

tephra

it is worth noting that certain rock names slate, schist, and gneiss are also used to describe rock ___.

texture

If the ripple marks were formed by air or water moving in essentially one direction,

their form will be asymmetrical

Because of accelerated erosion on steep slopes, the soils are ____ or in some cases nonexistent.

thin

Mount Etna, on the other hand has erupted once every ______________ years since 1979

2

migmatites serve to illustrate that some rocks are transitional and do not fit neatly into any of the ____ basic rock groups.

3

Most magmas have ______components. 1. 2. 3.

3 1. liquid component 2. solid component 3. gaseous component

How many ways can foliation occur?

3 ways

Today, __________________ is just one of the scores of cinder cones dotting the landscape in this region of ___________________.

Paricutin Mexico Like the others, it will not erupt again.

Rocks with compositions between granitic and basaltic rocks are said to have an ________________ composition or ___________________ composition, after the common volcanic rock ___________________.

andesitic composition or intermediate composition andesite

A few years earlier, a collapsed lave dome at the summit of Japan's Mount _____ produced a ________________________ __________ that claimed 42 lives

Unzen Pyroclastic flow Many of the victims were journalists and filmmakers who ventured too close to the volcano in order to obtain photographs and document the event.

Oil and natural gas are generated from the remains of marine plants and ______, mainly microscopic plankton, which died in ancient sea millions of years ago. This organic material was deposited in sedimentary basins together with mud, sand, and other sediments that protected it from oxidation. with increased temperature and burial, chemical reactions gradually transforms this organic matter into the liquid and gaseous hydrocarbons we call petroleum and natural gas.

animals

Gneisses made up of primarily dark minerals also occur. For example: an amphibole rich rock that exhibits a gneissic texture is called ___

amphibolite

The composition of volcanic gases is important because these gases contribute significantly to our planet's ______________.

atmosphere

This major greenhouse gas plays a significant role in the heating of our

atmosphere

certainly, one of the most active parts of the carbon cycle is the movement of CO2 from the atmosphere to the biosphere and back again. In the ___, carbon is found mainly as carbon dioxide.

atmosphere

Because silica-rich magmas are sticky (viscous) a significant portion of the gaseous material remains dissolved until the magma nears Earth's surface, at which time tiny _____________ begin to form and grow.

bubbles

This designation is correct because coal is ________, energy from the Sun that was stored by plants millions of years ago is being used, hence, the actual burning of "fossils"

burned

Environments where rocks may be carried to great depths and heated include ____ plate boundaries where slabs sediment - laden oceanic crust are being subducted.

convergent

Igneous rocks are exposed only at ___ of midocean ridges and at some volcanic areas.

crests

The general thickening of the ____ that occurs during mountain building results in buoyant lifting, in which deformed rocks are elevated high above sea level.

crust

Although the mineral portion of the soil is usually greater than the organic portion, humus is an essential component. In addition to being an important source of plant nutrients, humus enhances the soil's ability to retain ____.

water.

Evaporites

waters of the bay became saturated, and salt deposition began such deposits are called evaporites

If these iron - rich components are separated from the liquid by ______________ ________, the remaining melt will have an andesitic composition. These evolved (changed magmas) are termed _______________ ______________.

crystal settling

In this elevated level of activity, individual atoms migrate more freely between sites in the ______ structure.

crystalline

During the last stage of cooling, the magma body is like a __________________ _______________, resembling a bowl of thick oatmeal that contains only small amounts of melt.

crystalline mush

soil profile

image

solid-state flow

image

solum

image

spheroidal weathering

image

staurolite

image

steep slope in soils

image

steep slopes

image

travertine

image

limestone

image is composed of the mineral calcite, is the parent rock of marble

Kaolinite

image is one example of a clay mineral

shale

image is the most likely parent of most 1. slate 2. phyllite 3. schist 4. gneiss This sequence of metamorphic rocks reflects an increase in grain size, a change in rock texture, and a change in mineralogy.

granite porphyritic Some granites have a _________________ ______________________. These specimens contain elongated feldspar crystals a few centimeters in length that are scattered among smaller crystals of quartz and amphibole.

image porphyritic texture

Granite

image is the most abundant continental rock consists of quartz and potassium feldspar

Because of their iron content, __________ rocks are typically darker and _____________ than _________ rocks.

mafic denser granitic

Partial melting of ultramafic rocks yields ________________ or _____________ magmas.

mafic or basaltic

Rock characteristics encompass all of the chemical traits of rocks, including 1. 2.

mineral composition solubility

This air is the source of necessary ___ and ___ ___ for most microorganisms that live in the soil

oxygen carbon dioxide

Here, smooth-surfaced ________________ lava formed a lava lake.

pahoehoe

As a volcano matures, material also tends to be emitted from fissures that develop along the flanks or at the base of the volcano. Continued activity from a flank eruption may produce one or more small _____ cones.

parasitic cones

Every metamorphic rock has a _____ rock, the rock from which it was formed.

parent

formation of peat

partial decomposition of plant remains in an oxygen poor swamp creates a layer of peat, a soft brown material in which plant structures are still easily recognized. with shallow burial, peat changes to lignite, a soft brown coal burial increases the temperature of sediments as well as the pressure on them

Most magma is generated by _________________ ____________- of the the rock in the upper mantle and has a basaltic composition.

partial melting

The first mineral to crystallize is the ferromagnesian mineral _________________.

olivene

Soil fertility is in part related to the amount of __ matter present.

organic

The decay of plant and animal remains causes the formation of various _____ _____.

organic acids

obsidian is a dark colored glassy rock that usually forms when highly _______________ - rich lava cools quickly at Earth's surface. In contrast to the orderly arrangement of ions characteristic of minerals, the arrangement of _________________ in glass is unordered. Consequently, glassy rocks such as ________________ are not composed of __________________ in the same sense as most other rocks.

silica ions obsidian minerals

When chemically weathered, silicate minerals yield 1. 2. 3. 4.

sodium calcium potassium magnesium that form soluble products, which may be removed by groundwater.

Because of their mobility, these ion rich solutions can migrate great distances through the surrounding rock before they are eventually deposited, usually as _______________-- of various metals.

sulfides

The eruption of Kilauea that began in 1983 has been ongoing for more than ___ years

30

Prior to the appearance of humans sediment transported by rivers to oceans was over

9 billion metric tons per year

2. Hawaiian-Type Caldera

-unlike Crater Lake-type calderas, many calderas form gradually because of the loss of lava from a shallow magma chamber underlying the volcano's summit Hawaii's active shield volcano, Mauna Loa and Kilauea, both have calderas at their summits

Rhyolitic (felsic) flows make up ____%

1

In one study, half of all cinder cones examined were constructed in less than ___ month.

1 month and 95% were formed in less than 1 year..

3 and 4 continued

3. deposition of solid particles occurs when wind and water currents slow down and as glacial ice melts

One of the most destructive volcanic events, called the Laki eruptions began along a large fissure in southern Iceland in 1783.

3.4 cubic miles of fluid basaltic lavas 130 million tons of sulfur dioxide and other poisonous gases were released when sulfur dioxide is inhaled, it reacts with moisture in lungs to make sulfuric acid. this eruption's sulfur dioxide release cause the death of more than 50 percent of Iceland's livestock crop failure in parts of Western Europe thousands died from lung-related diseases a recent report estimates that a similar eruption today would cause more than 140,000 cardiopulmonary fatalities in Europe alone

What are the mobile agents that transport rock debris? 1. 2. 3. 4.

Wind Waves Glacial ice Running water

-the word sedimentary refers to this process; derived from latin sedimentum = to settle

a reference to solid material settling out of a fluid (water or air) examples: 1. floor on a lake 2. delta at the mouth of a river 3. gravel bar in a stream bed 4. particles in a desert sand dune 5. household dust

Schistosity

At higher temperatures and pressures, the minute mica and chlorite flakes in slate begin to recrystallize into larger muscovite and biotite crystals. When these platy minerals are large enough to be discernible with the unaided eye, they exhibt planar or layered structures called schistosity. Rocks that have this type of foliation are referred to as a schist. In addition to containing platy minerals, schist often contains deformed quartz and feldspar crystals that appear flattened or lens shaped and are embedded among the mica grains.

Hence, a mantle -derived magma changes chemically as it rises by assimilating silica - rich crustal rocks.

At the same time, extensive magmatic differentiation occurs, which means formation of secondary magma from parent magma.

Another group of volcanoes are the Seamounts that form along the crest of the mid-ocean ridges.

At these depths of 1 - 3 km below sea level, the pressures are so intense that the gases emitted quickly dissolve in the seawater and never reach the surface.

1783 eruption in Iceland, the atmospheric circulation around the globe appears to have been affected.

Drought in the Nile River valley and in India winter of 1784 brought the longest period of below zero temperatures in New England's history

Why is weathering important?

Many of life-sustaining minerals and elements found in soil, and ultimately in the food we eat, were freed from solid rock by weathering processes. Contributes to the formation of Earth's most spectacular scenery.

1902 pyroclastic flow and associated surge from Mount Pelee', a small volcano on the Caribean island of ____________________, destroyed the port town of St. Pierre.

Martinique

On exception is the cinder cone in _____________, which has erupted more than _____ times since it formed in 1850.

Nicaragua 20

The horizon from the surface downward are designated as 1. 2. 3. 4. 5.

O horizon A horizon E horizon B horizon C horizon

The Ring of Fire exists because oceanic lithosphere is being subducted beneath most of the landmasses that surround the ____ _____.

Pacific Ocean

One of the largest and most studied of all sills in the United States is the _____________ _____.

Palisade Sill. located along west bank of the Hudson River in southeastern New York and northeastern New Jersey

One of the very few volcanoes studied by geologists from its very beginning is the cinder cone called _____________.

Paricutin

These built an aesthetically pleasing cone, while fine ash fell over a much larger area, burning and eventually covering the village of ___________.

Paricutin

4. deposition of material dissolved in water is not related to the strength of water currents.

Rather, ions in solution are removed when chemical or temperature changes cause material to crystallize and precipitate or when organisms remove dissolved materials to build shells

Examples of exfoliation domes

Stone Mountain, Georgia Half Dome and Liberty Cap in Yosemite National Park

Large mantle plumes, dubbed __________________, are thought to be responsible for the vast outpourings of basaltic lava that created the large basalt provinces.

Superplumes

People often do not realize the importance of nonmetallic minerals because they see only the products that resulted from their use and not the minerals themselves.

That is, many nonmetallic minerals are used up in the process of creating other products.

Bowen and his coworkers demonstrated that as ____________________ magma cools, minerals tend to crystallize in a systematic fashion, based on their melting temperatures.

basaltic

If partial melting of mantle rocks generates most _______________ magmas, what is the source of the magma that crystallizes to form andesitic or ( intermediate) and granitic (felsic)rocks?

basaltic

Partial melting of mantle rock at spreading centers produces _______________ magma.

basaltic

Recall that the partial melting of mantle rock (peridotite) generates magma having a ___________ composition.

basaltic

Shield volcanoes owe their shape to fluid __________________ lavas.

basaltic

The pyroclastic material tends to have _______________ composition.

basaltic

Extensive study of the hawaiian islands revealed that they are constructed of a myriad of thin _______________ lava flows averaging a few meters thick, intermixed with relatively _______________ amounts of pyroclastic ejected material

basaltic minor

By contrast, ____________________ magma, which is low in silica forms very fluid lavas that, upon cooling, usually generate ______________ -grained crystalline rocks. However, when a basaltic lava flow enters the ocean, its surface is quenched rapidly enough to form a thin, _______________ skin.

basaltic fine-grained glassy

What color is obsidian? Obsidian has a chemical composition that is roughly equivalent to that of the light-colored ___________________ rock granite, not like dark rocks such as _____________________. Obsidian's dark color results from small amounts of _____________________ ions in an otherwise relatively clear, glassy substance.

black or reddish-brown igneous basalt metallic

Their upper surface consists largely of massive, detached blocks, hence the name _____________ ___________.

block lava Similar to aa flows, these lavas consist if blocks with slightly curved, smooth surfaces, rather than the rough, sharp, spiny surfaces typically of aa flows

volcanic breccia Particles in volcanic _____________ may consist of streamlined lava blobs that solidified in air, blocks broken from the walls of the vent, ash, and glass fragments.

breccia

Dikes and sills are typically shallow features, occurring where the country rocks are sufficiently ________________ to fracture. They can range in thickness from less than 1 millimeter to more than 1 kilometer

brittle

In low temperatures, rocks are ______.

brittle 1. tend to fracture 2. continued deformation grinds and pulverizes the mineral grains into small fragments

Diagenesis

burial promotes diagenesis because as sediments are buried, they are subjected to increasingly higher temperature and pressure occurs within the upper few km of Earth's crust as temperatures are generally less than 150 to 200 degrees C.

The mineralogy of an igneous rock depends on the _________________ makeup of its parent magma.

chemical

In addition, schists may be composed largely of minerals chlorite or talc, in which case they are called 1. 2.

chlorite schist talc schist Both chlorite and talc schists can form when rocks having basaltic compositions undergo metamorphism

These eruptions tend to steepen the slope of summit area, which often becomes capped with clusters of _____________ ______________.

cinder cones

Though a variety of minerals and rock fragments called ______may be found in detrital rocks 1. 2. are the constituents of most sedimentary rocks in this category.

clasts clay and quartz

Pyroclastic flows are generated by the ___________________ of tall eruption columns during an _________________________ event.

collapse explosive

Minerals containing the elements _______________, __________________, _________________________ and the rare earths are occasionally found

lithium cesium uranium and rare earths

A sandstone containing significant amounts of feldspar and angular grains of ferromagnesian minerals underwent ____ chemical weathering and transport and was probably deposited ____ to the source area of the particles.

little close

Basaltic rocks contain a high percentage of _______________________ minerals, so geologists also refer to them as ______________ (from __________ and _________________, the Latin name for iron.)

ferromagnesian mafic (ma)gnesium and (fe)rrum

Because peridotite is composed almost entirely of ___________________ minerals, its composition is referred to as ______________________. Ultramafic rocks are rare at Earth's surface, but ________________ is the main constituent of the upper mantle.

ferromagnesian minerals ultramafic peridotite

When magma intrudes rocks at shallow depths, the ____ cools and releases heat, which bakes the surrounding host rock.

magma

________________ is the parent material for igneous rocks, is formed by partial melting that occurs at various levels within Earth's crust and upper mantle to depths of about 250 kilometers (about 150 miles).

magma

Most pegmatites are ________________ in composition and consists of unusually large crystals of ____, _____, & ___________.

granitic quartz feldspar muscovite

Hot mineral-laden fluids, called hydrothermal solutions, contribute to metamorphism by enhancing the recrystallization of existing ___________________.

minerals

However, _______________melt at different temperature

minerals

Porphyroblastic textures develop In a wide range of rock types and metamorphic environments when minerals in the parent rock recrystallize to form new _____________.

minerals

By contrast, when shale is metamorphosed to slate, the clay minerals are recrystallized and become new _____, usually ___ and ____

minerals chlorite and muscovite

Rather than being concentrated in narrow veins and dikes, these ores are distributed as_______________________ masses throughout the entire rock mass.

minute

Most rhyolitic lavas seldom travel more than a few ____________ from their vents.

kilometers

When organic matter is decomposed, important ___ are supplied to plants, as well as to ____ and ____living in the soil.

nutrients plants animals

In high grade metamorphism, such features as bedding planes, fossils and vesicles that existed in the parent rock are ______.

obliterated

In diamond-bearing pipes, nearly the entire pipe contains diamond crystals that are disseminated throughout an ultramafic rock called

kimberlite

Sandstone

is the name given to rocks in which sand-size grains predominate after shale, sandstone is the next most abundant sedimentary rock, accounting for 20 % of the entire group

Gneiss

is the term applied to medium - to - coarse grained banded metamorphic rocks in which granular and elongated (as opposed to platy) minerals predominate most common minerals 1. quartz 2. potassium feldspar 3. plagioclase feldspar

The effect of cooling on rock textures is straightforward. 1. slow cooling promotes the growth of ___________ crystals. 2. Rapid cooling tends to generate _______ crystals.

large small

A horizon

largely mineral matter biologically active humus together A and O make up the topsoil

Differential stress

occurs at convergent plate boundaries where slabs of lithosphere collide. here the forces that deform rock are unequal in different directions and referred to as ___ ___.

Sorting

all the particles in sandstone are not neccessarily identical in size refers to the degree of similarity in particle size in a sedimentary rock

Metamorphism

also alters a rock's texture, producing larger crystals and sometimes distinct layering or banded appearance

Hydraulic fracturing

also called hydraulic fracturing often called fracking

removal of vegetation

also exposes the ground to strong direct sunlight when baked by the sun, these tropical soils can harden to a brick-like consistency and become practically impenetrable to water and crop roots.

Chemical weathering involves the complex processes that ____ the internal structures of minerals by removing and/or adding elements.

alter

Below the ridge axis where lithospheric plates are continually being pulled apart, the solid yet mobile mantle responds by _____________ to fill the rift.

ascending

Pyroclastic rocks composed mainly of particles larger than ______are called ______________ _____________.

ash volcanic breccia

Caldera-forming eruptions are of colossal proportions, ejecting huge volumes of pyroclastic materials, mainly in the form of

ash and pumice fragments These materials form pyroclastic flows that sweep across the landscape, destroying most living things in their paths. Upon coming to rest, the hot fragments of ash and pumice fuse together, formed a welded tuff and closely resembles a solidified lava flow. Despite the immense size of these calderas, the eruptions that cause them are brief, lasting hours to perhaps a few days.

Volcanic eruptions can eject dust-sized particles of volcanic ash and sulfur dioxide gas high into atmosphere

ash particles reflect solar energy back to space, producing temporary atmospheric cooling

Based on the extraordinary volume of erupted material, researchers have determined that the magma chambers

associated with Yellowstone-type calderas must be similarly monstrous As more and more magma accumulates, the pressure within the magma chamber begins to exceed the pressure exerted by the weight of the overlying rocks An eruption occurs when the gas-rich magma raises the overlying crust to create vertical fractures that extend to the surface. Magma surges upward along these cracks, forming a ring-shaped eruption. With a loss of support, the roof of the magma chamber collapses.

One result of fossil-fuel combustion is the release of huge quantities of CO2 into the ______.

atmosphere

The emplacement of small intrusions such as dikes and silles typically form aureoles only a few centimeters thick. By contrast, large molten bodies that cool to form batholiths can produce _______________ that extend outward for several kilometers.

aureoles

In the broadly folded Appalachians of central Pennsylvania, the rocks that once formed flat-lying beds are folded and display a preferred orientation of _____ mineral grains, as exhibited by well-developed slaty cleavage.

platy

These new ___minerals grains grow so they are aligned roughly perpendicular to the maximum directional stress.

platy

In ____ regions, chemical weathering is ____ because frigid temperatures keep the available moisture locked up as ice.

polar ineffective

2010, eruption of Iceland's Eyjafjallajokull Volcano, sent high ash into the atmosphere

the thick plume of ash drifted into Europe causing airlines to cancel thousands of flights, leaving hundreds of thousands of travelers stranded.

Contact metamorphism, also known as ___________ metamorphism occurs in Earth's upper crust (low pressure), when rocks immediately surrounding a molten igneous body are baked (high temperature)

thermal

conglomerate

these particles range in size from large boulders to particles as small as peas

Felsic (rhyolitic) lavas are very viscous and tend to form short, _______________ flows.

thick

Hot, wet climate may produce a ____ layer of chemically weathered soil in the same amount of time that a cold, dry climate produces a thin mantle of mechanically weathered debris.

thick

What kind of soils are found in the rain forest?

thick red - orange soils called oxisols are common to wet tropics and subtropics end product of extreme chemical weathering because lush tropical rain forests are associated with these soils, many people assume that they are fertile and have great potential for agriculture these are the poorest soils for farming

Crustal ____ also results in the deep burial of large quantities of rock as one crustal block is thrust beneath another.

thickening

Most igneous and sedimentary rocks consists of mineral grains or crystals that have a _____ orientation and thus appear uniform when viewed from any direction.

random

On the other hand, when cooling occurs __________ for example in a thin ____ flow--the ions quickly lose their mobility and readily combine to form __________________. This results in the development of _____________embryonic nuclei, all of which compete for the available ions. The result is a solid mass of ____________ intergrown cystals.

rapidly lava crystals numerous tiny

geothermal gradient

rate of increase in temperature with depth in the upper crust, this increase averages 25 degrees C per kilometer.

In increasingly hotter environments, these fluids become correspondingly more ________.

reactive

The formation of new mineral grains that tend to be larger than the original grains is called ____.

recrystallization

Some quartz remains in the soil, and is transported to the sea or to other sites of deposition, where it becomes the main constituent of such features as ____ ____ and ___ dunes

sandy beaches sand dune

As we move farther eastward, into the intensely deformed crystalline Appalachians, we find large outcrops of _____.

schists

Cinder cones are also called

scoria cones

Impact or _____ metamorphism occurs when high - speed projectiles called meteorites (fragments of comets or asteroids) strike Earth's surface.

shock

Sediment accumulations that exhibit poor sorting usually result when particles are transported for only a relatively ____ ____ ____ ___ ___. Example: when a turbulent stream reaches the gentler slopes at the base of a steep mountain, its velocity is quickly reduced, and poorly sorted sands and gravels are deposited.

short time and rapidly deposited.

In contrast to fluid basaltic magmas that can travel many kilometers, viscous andesitic and rhyolitic magmas tend to generate relatively ______________ prominent flows.

short.

A magma's viscosity is directly related to its _________________ content.

silica

An important aspect of chemical composition of igneous rocks is ____________(SiO2) content.

silica

Recall from our discussion of Bowen's reaction series that as basaltic magma solidifies, the _______________ poor ferromagnesian minerals crystallize first.

silica

Rocks that are relatively low in ___________ contain large amounts of iron, magnesium, and calcium

silica

So, granitic magma, which is rich in _______________________, may be extruded as an extremely viscous mass that eventually solidifies to form obsidian.

silica

The _______________ rich magmas typical of composite cones generate thick, viscous lavas that travel less than a few kilometers.

silica

The amount of ______________ present in magmas strongly influences its behavior.

silica

The more ______________ in magma, the greater is viscosity. Silica impedes the flow of magma because silicate structures start to link together into long chains early in the crystallization process.

silica

On the Big Island of Hawaii, these lavas have been clocked at 19 miles per hour down steep ______________. Flow rates of 30 to 1000 feet per hour are more common.

slopes

These current ripple marks will have steeper sides in the downcurrent direction and more gradual ____ on the upcurrent side.

slopes

For up to 24 hours before an eruption, swarms of ___________________________ warn of the impending activity

small earthquakes

In the final stage of growth, shield volcanoes erupt more ____________________________, and __________________________ ejections are more common.

sporadically pyroclastic

During this transformation, the original rock decomposes into substances that are ____ in the surface environment.

stable

As an industrial mineral, limestone is an ingredient in the manufacture of _____ and is used in agriculture to neutralize acid soils.

steel

Cinder cones have high angle of repose (the steepest angle at which material remains stable are are therefore ______-sided, with slopes between 30 and 40 degrees.

steep

This may explain why Mauna Kea, which is more mature volcano that has not erupted in historic times, has a _________________ summit than Mauna Loa, which erupted in 1984.

steeper

5 peaks of Henry Mountains are not laccoliths but _____________.

stocks

Hot basaltic lavas, which are usually very fluid, generally flow in thin, broad sheets or ________________ ribbons.

streamlike

Particles washed by waves are commonly better sorted than materials deposited by _______

streams

Upon mixing with the cold seawater, _____ and ________ minerals containing these heavy metals precipitate to form metallic deposits. Geologists credit this process with the formation of the ____ ores mined today on the Mediterranean island of Cyprus.

sulfides and carbonate copper

Coal contains ___. Despite efforts to remove sulfur before the coal is burned, some remains. When coal is burned, the sulfur is converted into noxious sulfur dioxide gas. Through a series of complex chemical reactions in the atmosphere, sulfur dioxide is converted to sulfuric acid, which eventually falls to Earth's surface in acid or snow. This acid precipitation can have adverse ecological effects over widespread areas.

sulfur

_____________compounds are easily recognized by their pungent odor.

sulfur

Volcanoes are natural sources of pollution; some emit ______________________, which combines with atmospheric gases to form sulfuric acid and other sulfate compounds

sulfur dioxide

Burrowing animals further break down rock by moving fresh material to the _____, where physical and chemical processes can more effectively attack it.

surface

The newly formed magma, which is less dense than surrounding rock, slowly rises toward the ____________________.

surface

Igneous rocks that form when molten rock solidifies at the __________________ are classified as _______________________ ____________________ _________________. They are also called ___________ rocks, after Vulcan, the Roman fire god.

surface extrusive igneous rocks volcanic rocks

Thus, while sediment and sedimentary rocks make up only a small percentage of Earth's crust, they are concentrated at or near the _______________

surface, the interface among the geosphere, hydrosphere, atmosphere, and biosphere

These low-density clouds called ____________ can be deadly but seldon have sufficient force to destroy buildings in their path.

surges

As magma continues to lose heat to its ___________, the ____________________ join with each other and with other ions to form ___________ crystal _______________. Slowly each nucleus grows as ions lose their mobility and join the crystalline network.

surroundings, tetrahedra embryonic crystal nuclei

Other ripple marks have a ____ form. These features, called _____ ____ ____, result from the back and forth movement of surface waves in a shallow near shore environment.

symmetrical oscillation ripple marks

Because of these differences, intrusive igneous bodies are classified according to their shape as either _________________________ or ________________________ and by their orientation with respect to the host rock.

tabular or massive

Some intrusions or plutons have a _________________ or _______________shape, whereas others are best described as ____________________________ (blob shaped).

tabular or tablet massive or blob shape

Although many fractures are created by expansion, others are produced by contraction during the crystallization or magma, and still others are produced by ______ forces during mountain building.

tectonic

Rocks and sediments can also be carried to great depths along convergent boundaries where oceanic lithosphere is being subducted. In this setting, cold, dense oceanic crust and sediments, which are poor conductors of heat, are subducting rapidly enough that pressure increases faster than ___. This phenomenon called ____ zone ____, differs from burial metamorphism in the differential stress plays a major role in DEFORMING rock as it is being metamorphosed.

temperature subduction zone metamorphism

As the _____________ of the liquid drops, ions pack more closely together as their rate of ______________ slows.

temperature movement

As ____________ rises, ions vibrate more rapidly and consequently collide with ever-increasing vigor with their ________________.

temperature neighbors

___ and ____ also exert a strong influence on rates of chemical weathering and on the kind and amount of vegetation present.

temperature and moisture

Sills

tend to accumulate magma and increase in thickness

A very large magma body located many kilometers beneath Earth's surface will cool over a period of _____________________________________. Initially, relatively few crystal ____________ form. Slow cooling permits ions to migrate freely until they eventually join one of the existing crystals. Consequently, slow cooling promotes the _____________ of fewer but ______________ crystals.

tens of thousands to millions of years nuclei growth larger

When such slopes are farmed, _____________can be constructed.

terraces

The ____________________ is used to describe the overall appearance of a rock based on the size, shape, and arrangement of its mineral grains --not how it feels to touch.

texture

How are igneous rocks classified?

texture mineral composition

Because igneous rocks are classified on the basis of both mineral composition and texture, some rocks having similar mineral constituents but exhibiting different ________________________ are given different names

textures

Geologists estimate

that these two categoriesof igneous and metamorphic rocks represent 90 to 95 % of the outer 10 miles of the crust

soil

the bridge between life and the inanimate world

volcanic cone

the cone-shaped structure we call a __ __ is often created by successive eruptions of lava, pyroclastic material, or combination of both

The magma generated in the mantle may change from a fluid basaltic magma to a silica rich andesitic or rhyolitic magma as it moves up through ____

the continental crust

recrystallization

the development of more stable minerals from less stable ones ex: aragonite recrystallizes to the more stable calcium carbonate

Glass results when ______________ ions are frozen in place before they are able to unite into an orderly crystalline structure. ___________________, a common type of natural glass is similar in appearance to dark chunks of manufactured glass.

unordered obsidian

Occasionally, the lake overflowed, but more often lava escaped through ____________ to feed flows that moved down the southeastern flank of the volcano toward the sea.

tunnels

Graded bed is most associated with a _____ current, a mass of sediment-choked water that is denser than clear water and that moves down slope along the bottom of a lake or an ocean,

turbidity

It is estimated that flowing water is responsible about

two-thirds of the soil erosion in the U.S.

In nature, over periods of thousands of years, large quantities of limestone are dissolved and carried away by __________________________ water.

underground ex: seen by the large number of subsurface caverns found in every one of the 48 states

It is best to leave steep slopes _________________.

undisturbed

It takes place due to the great reduction in pressure that occurs as the overlying rock is eroded away, a process called ______________.

unloading

When dry condition prevail, strong winds can remove large quantities of soil from ____ fields

unprotected

Because all intrusions form far below Earth's surface, they are studied primarily after __________________ and ___________________ have exposed them.

uplifting and erosion

Why are soils classified?

useful for agricultural and related land-use purposes, but it is not useful system for engineers who are preparing evaluations of potential construction sites

pillow lavas

useful in reconstruction of geologic history because their presence indicates that the lava flows formed below the surface of a water body

Some of these fluids move along openings such as fractures or bedding planes, where they cool and precipitate metallic ions to produce ___ ___

vein deposits

By the summer of 1986, a new _______ opened 2 miles downrift.

vent

During the night, hot, glowing rock fragments were ejected from the __________, producing a spectacular fireworks display.

vent

Once the event ceases, the magma in the plumbing connecting the _______ to the magma source solidifies, and volcano usually does not erupt again.

vent

Most of the volume of a cinder cone consists of pea to walnut sized fragments that are markedly __________________ and have a black to ________________________ color

vesicular reddish-brown

Lavas increase in ____________________, resulting in thicker, shorter flows

viscosity

In contrast to hot basaltic lavas, cool silica -rich rhyolitic lavas are so __________ that they hardly flow at all.

viscous

Plants and animals play a ____ role in soil formation

vital

Most metamorphic rocks have the same overall chemical composition as the parent rocks from which they formed except for the possible loss or acquisition of ____ such as water and carbon dioxide

volatiles

Water and other ____________________ act as salt does to melt ice.

volatiles

The gaseous components of magma, called ___________________, are materials that vaporize (form a gas) at surface pressures. Name 3 volatiles 1. 2. 3.

volatiles 1. water vapor 2. carbon dioxide (CO2) 3. sulfur dioxide (SO2)

magmas contain varying amounts of dissolved gases called __________________

volatiles, held in the molten rock by confining pressure, just as carbon dioxide is held in cans and bottles of soft drinks

Substantial weathering and long transport lead to the gradual destruction of ___ and less stable minerals, including the ____ and ____.

weaker feldspars and ferromagnesian

When hot ash falls, the glassy shards often fuse to form a rock called ____________ __________.

welded tuff Sheets of this material as well as ash deposits that later consolidate, cover vast portions of the western United States

If all the grains in a sample of sandstone are about the same size, the sand is ____ _____

well sorted

mature soil

well-developed soil profile indicates that environmental conditions have been relatively stable over an extended time span

Welded tuff deposits cover vast portions of previously volcanically active areas of ________________ U.S.

western

mineral calcite

which composes the common building stones marble and limestone is easily attacked by even a weakly acidic solution

metamorphism

which means change form is a process that leads to changes in the mineralogy, texture, and sometimes chemical composition of the parent rock

coal

which provides a significan portion of our electrical energy is classified as a sedimentary rock.

Much of the remainder is caused by the

wind

An example of metasomatism is the formation of the mineral _________________ from calcite CaCO2, the primary ingredient in limestone.

wollastonite CaSiO3

Suspended blocks of unmelted host rock called __________________- are often found in hardened igneous bodies.

xenoliths

70 volcanoes expected each

year

Movement along a fault _____ fractures and pulverizes rock. The result is a loosely coherent rock called _____ ____, that is composed of broken and crushed rock fragments.

zone fault breccia

These large aureoles often consist of distinct _____ of mtetamorphism.

zones

sandstone rock

image

sandy beaches

image

schist

image

shale

image

sheet erosion

image

sillimanite

image

slate

image

soapstone

image

subduction zone metamorphism

image

surges in volcanoes

image

underground caverns

image

waterlogged soils

image

weathering

image

wedging in plants

image

wind erosion

image

wollastonite

image

Limestone

image 10% of total volume of all sedimentary rocks most abundant chemical sedimentary rock composed of calcite CaCO3 and forms either by inorganic means or as a result of biochemical processes those forms having a marine biochemical origin are by far the most common

recrystallization

image During this process, the mineralogy of the rock may or may not change.

Breccia

image If the large particles are angular rather than rounded.

Marble

image Marble is a crystalline metamorphic rock whose parent is limestone or dolostone pure marble is white and composed mainly of calcite because of its softness 3 on Mohs scale, marble is easy to cut and shape stones and monuments are carved Lincoln Memorial in D.C and Taj Mahal in India very susceptible to chemical weathering, because marble is made out of calcium carbonate

graywacke

image along with quartz and feldspar, this dark-colored rock contains abundant rock fragments and matrix more than 15% of graywacke's volume is matrix

Grading beds

image are another special type of bedding. In this case, the particles within a single sedimentary layer gradually change from coarse at the bottom to fine at the top. Graded beds are most characteristic of rapid deposition from water containing sediment of varying sizes.

Coquina

image biochemical limestone a coarse rock composed of poorly cemented shells and shell fragments

Australia's Great Barrier Reef

image develop in shallow, warm waters of the tropics and subtropics equatorward of about 30 degrees latitude

jasper

image example of chert red variety gets it bright color from iron oxide

agate

image example of chert the banded form agate precipitates in concentric rings within voids in a rock its striped appearance occurs by variations in impurities that occur while precipitation is taking place.

columnar jointing

image example: Giant's Causeway in Northern Ireland is an excellent example

pumice

image extrusive rock containing voids left by gas bubbles that escape as lava solidifies. Pumice is a frothy volcanic glass that displays vesicular texture.

dolostone

image forms when magnesium-rich waters circulate through limestone and convert calcite to dolomite through the replacement of some calcium ions with magnesium ions (process called dolomitization)

rhyolite is fine grained and frequently contains glass _____________ and _____________, indicating that it cooled __________________ in a surface, or ___________________ surface, environment.

image fragments and voids rapidly near

mud cracks

image indicate that the sediment in which they were formed was alternately wet and dry. When exposed to air, wet mud dries out and shrinks, producing cracks. Mud cracks are associated with such environments as tidal flats, shallow lakes, and desert basins.

1 large eruption every ______________.

decade

Soil erosion is a

serious environmental problem

ripple marks the ridges form at right angles to the direction of motion.

image

rock cycle

image

sand dune

image

andesite

1. medium gray fine - grained rock 2. typically of volcanic origin. 3. name comes from South America Andes Mountain, where numerous volcanoes are composed of this rock type 4. Volcanoes of Cascade Range and many of the volcanic structures occupying the continental margins that surround the Pacific Ocean are of andesitic composition.

Other examples of large calderas located in the United States

1. California's Long Valley Caldera 2. LaGarita Caldera, located in San Juan Mountains of southern Colorada 3. Valles Caldera west of Los Alamos, New Mexico These and similar calderas elsewhere around the globe are among the largest volcanic structures on Earth, hence the name "supervolcanoes". Volcanologists have compared their destructive force with that of the impact of a small asteroid

4 physical processes lead to the fragmentation of rock. 1. 2. 3. 4.

1. Frost wedging 2. Salt crystal growth 3. Expansion resulting from unloading 4. Biological activity

The volcanic structures comprise most of the islands of the deep-ocean basins, including the

1. Hawaiian Islands 2. Galapagos islands 3. Easter Island

Hydraulic fracturing

1. In some shale deposits, there are significant reserves of natural gas that cannot naturally leave because of the rock's low permeability 2. The practice of hydraulic fracturing shatters the shale, opening cracks through which the natural gas can flow into wells and then be brought to Earth's surface 3. The fracturing of the shale is initiated by pumping fluids into the rock at very high pressures 4. The fluid is mostly water but also includes other chemicals that aid in the fracturing process. 5. Some of these chemicals may be toxic, and there are concerns about fracking fluids leaking into aquifers that supply communities with freshwater. 6. The injection fluid also includes sand, so when fractures open in the shale, the sand grains can keep the fractures propped open and permit the gas to continue to flow. Because of concerns about potential groundwater contamination and induced seismicity, hydraulic fracturing remains a controversial practice.

Large calderas tend to exhibit a complex eruptive history.

1. In the Yellowstone region, for example, three caldera-forming episodes are known to have occurred over the past 2.1 million years. 2. The most recent event 630,000 years ago, was followed by episodic outpourings of degassed rhyolitic and basaltic lavas. 3. Geologic evidence suggests that a magma reservoir still exists beneath Yellowstone; thus another caldera-forming eruption is likely but not necessarily imminent

The heart of the Dust Bowl was nearly 100 million acres in the panhandles of 1. 2. 3. 4. 5.

1. Texas 2. Oklahoma 3. Colorado 4. New mexico 5. Kansas

where are intrusive igneous rocks found? 1. 2. 3 4.

1. WhiteMountains, New Hampshire 2. Stone Mountain, Georgia 3. Mount Rushmore in the Black Hills of South Dakota 4. Yosemite National Park, California

Stages in the formation of coal

1. accumulation of plant remains 2. formation of peat 3. formation of lignite and bituminous coal 4. formation of anthracite coal

ANDESITIC (INTERMEDIATE ROCKS) BEGINS HERE:

1. andesite 2. diorite

There are several common oil and natural gas traps 1. 2. 3. 4.

1. anticline 2. fault trap 3. salt dome 4. stratigraphic pinchout trap

chert deposits are found in one of two situations 1. 2.

1. as layered deposits referred to as bedded cherts and 2. as nodules, somewhat spherical masses varying in diameter from a few millimeters to a few centimeters

Basaltic (mafic) igneous rocks starts here:

1. basalt 2. gabbro

Dust storms were called

1. black blizzards 2. black rollers

Nonmetallic mineral resources are commonly divided into two broad groups: 1. 2. Because some substances have many different uses, they are found in both categories.

1. building material 2. industrial material

Bauxite forms in rainy tropical climates. When aluminum - rich source rocks are subjected to the intense and prolonged chemical weathering of the tropics, most of the common elements, including 1. 2. 3. are removed by leaching.

1. calcium 2. sodium 3. potassium

AT depth, hot water is released into the surrounding rocks when a magma body cools and solidifies. In addition, many minerals, including ___, ____, and ___, are hydrated --which means that contain water in their crystalline structures.

1. clays 2. micas 3. amphiboles

Most calderas are formed by one of the following processes 1. 2. 3.

1. collapse of the summit of a large composite volcano following an explosive eruption of silica rich pumice and ash fragments (Crater Lake - type calderas) 2. collapse of the top of a shield volcano caused by subterranean drainage from a central magma chamber (Hawaiian-type calderas) 3. collapse of a large area, caused by the discharge of colossal volumes of silica rich pumice and ash along ring fractures (Yellowstone - type calderas

Pyroclastic flows are composed of two parts: 1. 2.

1. low density cloud of hot expanding gases containing fine ash particles 2. ground-hugging portion that is often composed of pumice and other vesicular pyroclastic material

other metamorphic rocks that are produced by contact metamorphism are 1. 2.

1. marble = limestone is the parent of marble 2. quartzite = quartz sandstone is the parent of quartzite

Other eruptions that have produced significant effects on climate worldwide include: 1. Indonesia Mount Tambora in 1815 2. eruption of El Chichon in Mexico in 1982

1. produced the year without a summer (1816) 2. The eruption for El Chichon, although small, emitted an unusually large quantity of sulfur dioxide that reacted with water vapor in the atmosphere to produce a dense cloud of tiny sulfuric acid droplets. These particles, called aerosols, take several years to settle out of the atmosphere. Like fine ash, these aerosols lower the mean temperature of the atmosphere by reflecting solar radiation back to space

Purpose of slate:

1. roof and floor tiles 2. billiard table surface

Most metamorphic rocks that we observe at Earth's surface were derived from the three most common sedimentary rocks 1. 2. 3.

1. shale 2. limestone 3. quartz

The primary factors that affect the behavior of magma and lava are 1. 2. 3. These factors determine a magma's mobility or viscosity.

1. temperature and composition 2. amount of dissolved gases

Other sites of intraplate volcanisms meaning Within the plate include large outpourings of fluid basaltic lavas like those that compose : 1. 2. 3. 4.

1. the Columbia River basalts, 2. the Siberian Traps in Russia 3. India's Deccan Plateau 4. Several large oceanic plateaus including the Ontong Java Plateau located in the western Pacific (These massive structures are estimated to be 6 - 25 miles thick.

Where are extrusive igneous rocks found? 1. 2. 3.

1. western portions of Americas, where they make up the volcanic peaks of the Cascade Range and the Andes Mountains. 2. Many oceanic islands, including Hawaiian chain and Alaska's Aleutian islands

There are ___ main textures in sedimentary rock classification.

2 1. clastic 2. nonclastic

The amount of material currently transported to the sea by rivers is about

24 billion metric tons per year, or more than two and a half times the earlier rate

____% of the energy consumed in the U.S. comes from these basic fossil fuels.

82 %

Rocks that contain at least ____% dark silicate minerals and calcium rich ____________ feldspar (but no ______________) are said to have a ______________ composition.

45 % calcium - rich plagioclase feldspar (but no Quartz) basaltic

________%sulfur dioxide

5%

Kilauea's measures 2 by 3 miles and is ___________________deep. The walls of this caldera are almost vertical and as a result, it looks like a vast, nearly flat-bottomed pit.

500 feet

There are _____ igneous textures: anphantitic (fine grained) phaneritic (coarse grained) vesicular porphyritic glassy pyroclastic or fragmental

6

Displacement along California's San Andreas Fault have created a zone of fault breccia and related rock types more than _____ miles long and ____ miles wide.

600 miles long 2 miles wide

Across the ocean floor, which represents about ____% of Earth's solid surface, virtually everything is covered by sediment.

70 %

The temperature averages about _______________ per kilometer in the upper crust. This increase in temperature with ____________ is known as the ________________________ gradient.

75 F depth geothermal gradient

Granite continued

8. Other minor constituents include small amounts of dark silicates, particularly biotite and amphibole and sometimes muscovite 9. dark components make up less than 10% of most granites, dark minerals appear to be more prominent than their percentages indicates

Lava domes are usually only a few tens of meters high, and they come in a variety of shapes that range from pancake-like flows to a steep-sided plugs that were pushed upward like pistons. Most lava domes grow over a period of several years, following an explosive eruption of silica-rich magma.

A recent event is the dome that began to grow in the crater of Mount St. Helens immediately following the 1980 eruption.

Volcanic arcs can be constructed on oceanic as well as continental lithosphere. Those that develop within the ocean and grow large enough for their tops to rise above the surface are labeled ______ in most atlases.

Archipelagos

The volcanoes of the Cascade Range in the northwestern United States, included 1. 2. 3.

Are examples of volcanoes generated along a convergent plate boundary 1. Mount Hood 2. Mount Rainier 3. Mount Shasta

Time

As a rule, the longer a soil has been forming, the thicker it becomes and the less it resembles the parent material

All volcanoes succumb to forces of _______________ and ________________. Weathering and erosion.

As erosion progresses, the rock occupying the volcanic conduit, which is often highly resistant to weathering, may remain standing above the surrounding terrain long after the cone has been worn away.

Temperature

As lava cools and begins to congeal, its viscosity increases and eventually the flow halts

Other reefs

Bahamas Hawaii Florida Keys

How can you distinguish granite from diorite?

Because diorite contains little or no visible quartz crystals and has a higher percentage of dark silicate minerals. The mineral makeup of diorite is primarily plagioclase feldspar and amphibole. Because the light colored feldspar grains and dark amphibole crystals appear to be roughly equal in abundance, diorite has a salt and pepper appearance.

If a rock is _____, it may signify a dry climate, where little chemical alteration of feldspar is possible.

arkose

The ________________ Plateau located in northwestern United States, which consists of the Columbia River basalts, is the product of this type of activity.

Columbia Plateau

the silver deposits of the ________________ in Nevada

Comstock Lode

Sedimentary environments are placed into one of three categories 1. 2. 3

continental marine transitional (shoreline)

1. Crater Lake- Type Calderas

Crater Lake, Oregon, is situated in a caldera 6 miles wide and 3800 feet deep. formed 7,000 years ago composite cone, named Mount Mazama, extruded 12 to 17 cubic miles of pyroclastic material 1500 meters of the summit of this prominent cone collpased, producing a caldera that filled with rainwater Later, volcanic activity produced a small cinder cone called Wizard Island, provides a mute reminder of past activity

The rocks filling these pipes originated at great _______, where pressure is sufficiently high to generate ________________ and other high pressure minerals.

Depth Diamonds

In 1943, its eruptive phase began, in a cornfield owned by _______________ who witnessed the event as he prepared the field for planting.

Dionisio Pulido

Volcanic ash and aviation

During the 15 year, 80 jets have been damaged in flying into clouds of volcanic ash 1989 Boeing 747 carrying more than 300 people encountered an ash cloud from Alaska's Redoubt Volcano, engines stalled but were able to restart and land in Anchorage

Geologists consider pipes to be windows into ____________________ that allow us to view rocks that normally form only at great depths.

Earth

nonmetallic mineral resources

Earth materials that are not used as fuels or processed for the metals they contain are referred to as __ __ __.

Although most spreading centers are located along the axis of an oceanic ridge, some are not. In particular, the __________ _____ ____ is a site where continental lithosphere is being pulled apart.

East African Rift Vast outpourings of fluid basaltic lavas as well as several active composite volcanoes are found in this region of the globe.

The volcanic activity on Kilauea began along a series of fissures in the ____________ __ ___.

East Rift Zone

Along some ridge segments, outpourings of pillow lavas build numerous volcanic structures, the largest of which is _________

Iceland

mudstone

If the rock breaks into chunks or blocks

discordant intrusion

Igneous bodies are said to be ____________ if they cut across existing structures

concordant intrusion

Igneous bodies are said to be _____________ if they inject parallel to features such as sedimentary strata.

Bowen's reaction series

In a cooling magma, minerals crystallize in a specific order. 1. Ferromagnesian silicates such as olivine crystallize first, at the highest temperatures, 1250C 2. nonferromagnesian silicates such as quartz crystallize last, at the lowest temperature 650C 3. Bowen found that in between these temperatures, chemical reactions take place between the crystallized silicates and the melt, resulting in compositional changes in each and the formation of new minerals.

Chemical weathering

Involves a chemical transformation of rock into one or more new compounds

Weathering

Involves the physical breakdown (disintegration) And chemical alteration (decomposition) of rock at or near Earth's surface

Mechanical weathering

Is accomplished by physical forces that break rock into smaller and smaller pieces without changing the rock's mineral composition

Several months before each eruptive phase, _______________________inflates as magma gradually migrates upward and accumulates in a central reservoir located a few kilometers below the summit.

Kilauea

__________________ the most active and intensively studied shield volcano in the world, is located on the island of ___________________ in the shadow of Mauna Loa.

Kilauea Hawaii

The best known volcanic pipes are the diamond bearing -__________pipes of South Africa.

Kimberlite

From its base on the Pacific Ocean to its summit, ______________ Loa is over 6 miles high, exceeding the elevation of Mt. Everest

Mauna

Two basic categories of weathering 1. 2.

Mechanical weathering Chemical weathering

3. Flattening Spherically shaped grains

Mechanisms that flatten existing mineral grains are important in the metamorphism of rocks that contain minerals such as quartz, calcite, and olivine. these minerals develop spherical crystals and have a rather simple chemical composition a change in grain shape can occur as distinct units of a mineral's crystalline structure slide relative to one another along discrete planes, thereby distorting the grain. this type of gradual solid-state flow involves slippage that disrupts the crystal lattice as atoms shift positions by breaking existing chemical bonds and forming new ones

fig. 4.4

Mount Rushmore Memorial, Black Hillls of South Dakota is carved from intrusive igneous rocks 4 presidents

Figure 5.2 Douglas fir trees snapped off or uprooted by the lateral blast of

Mount St. Helens

When the activity became localized, a cinder and spatter cone, given the Hawaiian name ____ __, was built.

Puu Oo

Explosive degassing of the interior magma triggers a fiery _____________ flow that races down the flanks of the volcano.

Pyroclastic

When large masses of igneous rock, particularly granite are exposed by erosion, concentric slabs begin to break loose. The process that generates these onion-like layers is called ________.

Sheeting

____________, New Mexico, is a widely recognized and spectacular example of these structures geologists call ______ ____ or plugs.

Shiprock Volcanic necks or plugs

Soil scientists have devised a system for classifying soils known as the

Soil Taxonomy it emphasizes the physical and chemical properties of the soil profile and is organized on the basis of observable soil characteristics 6 hierarchical categories of classification, ranging from order, the broadest category, to series, the most specific category.

At one time the parent material was thought to be the primary factor causing differences among soils.

Soil scientists have come to understand that other factors, especially the climate are more important.

Since 1995, pyroclastic flows generated by the collapse of several lava domes on ___ ______________ _________.

Soufriere Hills Volcano have rendered more than half of the Caribbean island of Montserrat uninhabitable

Prior to the development of the theory of plate tectonics, geologists did not have an acceptable explanation for the distribution of Earth's___

Volcanoes

Example, when a fine grained limestone (made of calcite) is metamorphosed by the intrusion of a hot magma body, the small calcite grains recrystallize to form larger interlocking crystals.

The resulting rock, marble, exhibits large, intergrown calcite crystals.

The collapse of lava domes, particularly those that form on the summit or along the steep flanks of composite cones, may produce powerful pyroclastic flows.

These flows result from highly viscous magma slowly entering the dome, causing it to expand and steepen its flanks.

Because this newly formed magma is less dense than the mantle rock from which it was derived, it rises and collects in reservoirs located just below the ridge crest.

This activity continuously adds new basaltic rock to plate margins, temporarily welding them together, only to have them break again as spreading continues.

Why are the andesitic or intermediate so important?

This category of igneous rocks is associated with volcanic activity that is typically confined to the seaward margins of the continents and on volcanic island arcs such as the Aleutian chain.

Shape of a mineral may also be altered by a process in which individual atoms move from a location along the margin of the grain that is highly stressed to a low stressed position on the same grain.

This mechanism, called pressure solution, is significantly aided by hot iron-rich water. mineral matter (ions) dissolves where grains are in contact with each other (areas of high stress) and is deposited in pore spaces (areas of low stress) as a result, the mineral grains tend to become shortened in the direction of maximum stress and elongated in the direction of minimum stress.

Describe the different grades of metamorphism that might be encountered moving west to east from Ohio to the crystalline core

This systematic transition in metamorphic textures can be observed as we approach to Appalachian Mountains from the west. Beds of shale, which once extended over large areas of eastern U.S., still occur as nearly flat-lying strata in Ohio.

These volcanic chains develop roughly parallel to the associated ___________.

Trench at distances 200 to 300 km (100 to 200 miles)

Consequently, the products of chemical weathering remain essentially _____ as long as they remain in an environment similar to the one in which they formed.

Unchanged

Migmatite

Under high-grade metamorphism, light-colored (felsic) minerals in a gneiss may begin to melt, while the dark-colored (mafic) minerals remain solid. If this melt solidifies in place, the rock--called a migmatite--will contain light-colored igneous rock intermixed with metamorphic rock composed of dark-colored (mafic) minerals

Some of the most intense zones of metamorphism are found in ____ and___ ____, where gneissic rocks outcrop.

Vermont and New Hampshire

Section 5.2 The Nature of Volcanic Eruptions

Volcanic activity is commonly perceived as a process that produces a picturesque, cone-shaped structures that periodically erupts in a violent manner Many eruptions are not explosive

Volcanism at a convergent plate margin results in the development of a slightly curved chain of volcanoes called a ____________ ________.

Volcanic arc.

Geologists prefer the more descriptive term ________________ _______ _____or simply _______ _____

Volcanic island arcs Or island arcs

This causes the burst the burst of __________ that emits voluminous outpourings of lave to form a huge basalt province in a matter of million or so years.

Volcanism

The transformation of rock is what we call ________________

Weathering

potassium feldspar

When potassium feldspar is weathered, the hydrogen ion attach and replace potassium ions in the feldspar structure. Once removed, the potassium is available as a nutrient for plants or becomes the soluble salt potassium bicarbonate, which may be incorporated into other minerals or carried to the ocean in dissolved form by streams

Diamonds are used as

abrasives

quartz sandstone

after shale, sandstone is the next most abundant sedimentary rock

Name our 3 most indispensable resources 1. 2. 3.

air water soil

Because plants require ____ and ____ to live and grow, the portion of the soil consisting of pore spaces that allow for the circulation of these fluids is as vital as the solid soil constituents.

air water

The pore spaces that are not filled with water contain ___.

air.

soil orders

alfisol - vertisol

In metamorphic environments, foliation is driven by compressional stress that shortens rock units, causing mineral grains in preexisting rocks to develop parallel, or nearly parallel _______.

alignments

Gentle slopes

although shale is far more common than other sedimentary rocks, it does not usually attract as much notice as other, less abundant members of this group shale does not form prominent outcrops, as sandstone and limestone often do. Rather, shale crumbles easily and usually forms a cover of soil that hides the unweathered rock below.

Because ____ is extremely insoluble, it becomes concentrated in the soil as _____________________, a hydrated aluminum oxide. thus, the formation of bauxite depends on climatic conditions in which chemical weathering and leaching are pronounced plus, of course, the presence of aluminum-rich source rock.

aluminum bauxite

Whereas, the mafic silicates, such as ____ and ______ remain solid.

amphibole and biotite

the orientation of slate's cleavage usually develops at an _____ to the sedimentary beds.

angle

Each bedding plane marks the end of one episode of sedimentation and the beginning of ___________.

another

siltstone

another fine-grained sedimentary rock that, like mudstone, is often grouped with shale but lacks fissility is composed largely of silt-size particles and contains less clay-size material than shale and mudstone

lava

another image

obsidian If you examine a thin edge, obsidian will appear nearly _______________.

another image transparent

stratigraphic pinchout trap

another important geologic circumstance that may lead to significant accumulations of oil and gas These oil-bearing structures result from the original pattern of sedimentation rather than structural deformation. This stratigraphic trap exists because a sloping bed of sandstone thins to the point of disappearance

magma mixing

another means by which the composition of the magma can be altered. may occur during the ascent of two chemically distinct magma bodies as the more buoyant mass overtakes the more slowly rising body. Once they are joined, convective flow stirs the two magmas, generating a single mass that has an intermediate composition

oolitic limestone

another variety of inorganic limestone is composed of small spherical grains called ooids

corals

are capable of creating massive structures called reefs reefs consists of coral colonies made up of great numbers of individuals that live side by side on a calcite structure sectred by the animals calcium carbonate secreting algae live with the corals and help cement the entire structure into a solid mass

Sills

are nearly horizontal, concordant bodies that form when magma exploits weaknesses between sedimentary beds or other structures.

ash and dust

are produced when gas-rich viscous magma erupts explosively

clay minerals

are the most abundant product of chemical weathering of silicate minerals, especially the feldspars

In ___ regions where there is insufficient ___ to promote rapid chemical weathering is seen as well.

arid moisture

_________________ is the most common extrusive igneous rock. Many volcanic islands, such as the __________________________ Islands and _________________ are composed mainly of basalt.

basalt Hawaiian Iceland

Any such changes produces a gradual alteration of soil characteristics until a new _____ is reached.

balance

When marble forms from limestone interbedded with shale, it appears _____ and exhibits visible foliation. When deformed, these banded marbles may develop highly contorted mica-rich folds that enhance the rocks' artistic appearance. These decorative marbles have been used as building stones since prehistoric times.

banded

The inability of water to penetrate its microscopic pore spaces explains why shale often forms ___ to the subsurface movement of water and petroleum.

barriers

Due to the extreme nature of the eruption required to produce the large ______ provinces, some researchers believe the eruptions were responsible for the extinction of many of Earth's life-forms.

basalt

_____________________ is a very dark green to black, fine-grained rock composed primarily of pyroxene and calcium-rich plagioclase feldspar, with lesser amounts of olivine and amphibole.

basalt

Although granitic magmas can arise through magmatic differentiation of adesitic magmas, most granitic magmas probably form when hot ___________________ magma ponds below continental crust.

basaltic

most water-dwelling organisms that produce hard parts make them of

calcium-carbonate

Ash and pyroclastic material

can collapse roofs of buildings drawn into lungs of humans/animals get into aircraft engines emit gases, sulfur dioxide which affects air quality and when mixed with rainwater, may destroy vegetation and reduce the quality of ground water

In fact, the crust is by far Earth's largest depository of ___, where it is constituent of a variety of rocks, the most abundant being limestone.

carbon

When a silica- rich hydrothermal solution invades limestone, calcite reacts with silica to generate wollastonite, and the gas _______ is driven off.

carbon dioxide

Most carbon is bonded chemically to other elements to form compounds such as

carbon dioxide calcium carbonate hydrocarbons found in coal and petroleum

regions with lush vegetation have a thick mantle of soil rich in decayed organic matter from which chemically active fluids such as ___________ _________ and humic acids are derived.

carbonic acid

Confining pressure

causes the spaces between mineral grains to close, producing more compact rocks that have greater densities. does not fold or fracture rocks

The amount of pore space is reduced during _____.

compaction

Basic lithification processes include 1. 2.

compaction cementation

Batholiths

composed of felsic and intermediate rock types and referred to as "granite batholiths"

Although the mineralogy changes in the transition from shale to slate, the overall chemical ______________ remains essentially unchanged

composition

In addition to affecting the degree of rounding and the amount of sorting that particles undergo, the length of transport by turbulent air and water currents also influences the mineral _____ of sedimentary deposits.

composition

Once a magma forms, its __________________ can also change through the incorporation of foreign material.

composition

Soil components

composition by volume of a soil in good condition for plant growth; mineral and organic matter, water and air

Differential stress that squeezes a rock mass as it is were placed in a vise is termed _____ ____. Rocks subjected to compressional stress are shortened in the direction of greatest stress and elongated, or lengthened in the direction perpendicular to that stress.

compressional stress

these resources result from processes that ___________________ desirable materials to the extent that they can be profitably extracted.

concentrate

Weathering creates many important mineral deposits by ______ minor amounts of metals that are scattered through unweathered rock into economically valuable concentrations.

concentrating

Because of its excellent ________________ fracture and ability to hold a sharp, hard edge, _______________ was a prized material from which Native Americans chipped arrowheads and cutting tools.

conchoidal obsidian

The most widely recognized volcanic structures are the

cone-shaped edifices of composite volcanoes that dot Earth's surface

Buried rocks are subjected to ___ ____, which is analogous to water pressure, in which the forces are applied equally in all direction.

confining pressure

Unlike most building materials, which need a minimum of processing before they are ready to use, many industrial minerals require ___

considerable processing to extract the desired substance at the proper degree of purity for its ultimate use.

O, A, E, and B horizons together

constitute the solum or true soil solum that the soil forming processes are active and that living roots and other plant and animal life are largely confined

Crustal rocks can also melt during _____________________ collisions that result in the formation of a large mountain belt. During these events, the crust is greatly thickened, and some crustal rocks are buried to depths where the temperatures are elevated sufficiently to cause partial melting.

continental

When they are ______________ sufficiently, the forces of the chemical bonds again confine the ____________- to an _____________________ crystalline arrangement.

cooled ions orderly

The textures result from different _______________ histories.

cooling histories

It is estimated that topsoil is eroding faster than it forms on more than one-third of the world's ________________

coplands

Carbonate reefs

corals are one important example of organisms that are capable of creating large quantities of marine limestone. these simple invertebrates animals secrete a calcareous (calcium carbonate) external skeleton

Consequently, the __________ of many mountain belts consist of folded and faulted metamorphic rocks, often intertwined with _____________ bodies.

cores igneous

Moreover, deposits are far from more restricted in distribution and extent. As a result, many of these nonmetallic resources must be transported considerable distances, which of course adds to their ____.

cost.

Explosive discharges continued, throwing hot fragments and ash occasionally as high as 20,000 feet into the air. Larger fragments fell near the ____________, some remaining incandescent as they rolled down the slope.

crater

In addition, a cinder cone has a quite large, deep ______________ in relation to the overall size of the structure.

crater

Other craters form during explosive eruptions as the rapidly ejected particles erode the _____________ walls.

crater

Volcanoes built primarily of pyroclastic materials typically have _____________that form by gradual accumulation of volcanic debris on the surrounding rim.

craters

to explore this idea, N.L. Bowen carried out a pioneering investigation into the ________________________ of magma early in the 20th century.

crystallization

In the process of _________________, cooling reverses the event of ___________.

crystallization melting

The solid components (if any) in magma are _________________ of _________________ minerals.

crystals of silicate minerals As the magma body cools, the size and number of crystals increase.

Ripple marks produced by a stream flowing across a sandy channel and by wind blowing over a sand dune are two common example of _____ ____.

current ripples.

The first discharge began along a 4 mile fissure where 100 meter high ____________ of ______________ formed as red-hot lava was ejected skyward.

curtain of fire

____weathering and subsequent erosion are responsible for creating many unusual and sometimes ____________ rock formations and landforms.

differential spectacular

In 1980, May 18, 1980, the largest volcanic eruption to occur in North America in historic times transformed a picturesque volcanoe into a _________________ remnant

decapitated

When plants die and ____ or are _____, this biomass is oxided, and carbon dioxide is returned to the atmosphere.

decay burned

_________________- melting also occurs when ascending mantle plumes reach the uppermost mantle.

decompression

When confining pressure drops sufficiently, __________________ _____________ is triggered.

decompression melting

By understanding the conditions under which sedimentary rocks form, geologists can ____ the history of the rock, including information about the origin of is component particles, the method of sediment transport, and the nature of the place where the grains eventually came to rest --the environment of deposition

deduce

compressional forces of unimaginable magnitude and temperature hundreds of degrees above surface conditions prevailed for thousands or millions of years and produced th

deformation displayed by these rocks

Foliation is a fundamental characteristic of metamorphosed rocks that have been strongly ___, mainly by folding.

deformed

Elevated temperatures and pressures cause these minerals to ____, expelling hot, mineral - laden water

dehydrate

By studying the degree of sorting, we can learn much about the ____ ___.

depositing current

The size of the component grains also provide useful information about environments of __________.

deposition

Pressure, like temperature, increases with ____ because the thickness of the overlying rock increases.

depth

Chemical sediments

derive from ions that are carried in solution to lakes and seas. this material does not remain dissolved in the water indefinitely, however. some of it precipitates to form chemical sediments. these become rocks such as limestone, chert, and rock salt

In environments, where temperatures and pressures are more extreme, metamorphism causes a transformation so complete that the identity of the parent rock cannot be easily ________.

determined

All ___ rocks have clastic texture.

detrital

How do earthworms help?

earthworms and other burrowing animals act to mix the mineral and organic portions of the soil. Earthworm feed on organic matter and thoroughly mix soils in which they live, often moving and enriching tons per acre each year. Burrows and holes aid the passage of water and air through the soil.

While dikes and sills can occur as solitary bodies, Dikes tend to form in roughly parallel groups called _______________ ________. The multiple structures reflect the tendency for fractures to form in sets when tensional forces stretch brittle country rock.

dike swarms

hydrothermal and contact metamorphism do not involve ________________ stress

directional

Igneous bodies are said to be _____________________ if they cut across existing structures.

discordant

Dikes

discordant bodies that cut across bedding surfaces or other structures in the country rock.

Although relatively symmetrical, some cinder cones are elongated and higher on the side that was ______________ during the final eruptive phase.

downwind

When drilling punctures the lid created by the cap rock, the oil and natural gas, which are under pressure, migrate from the pore spaces of the reservoir rock to the ___ ___.

drill pipe

In high temperatures, high-pressure environments rocks are___.

ductile 1. mineral grains are flattened 2. ability to flow rather than fracture 3. creates folds

Because quartz is very ___, it is usually the mineral that survives a long trip in a turbulent environment.

durable

The _____________ formed minerals have space to __________________ and tend to have better-developed crystal faces than do the ones that form later and occupy the remaining spaces.

earliest grow

1. Rotation of platy mineral grains

easiest of the foliation mechanisms to envision new alignment is roughly perpendicular to the direction of maximum stress physical rotation of platy minerals contributes to the development of foliation in low-grade metamorphism, other mechanisms dominate in more extreme environments

When gravity overcomes the initial upward thrust provided by the escaping gases, the _____________ materials begin to fall, sending massive amounts of incandescent blocks, ash, and ________________ cascading downslope.

ejected pumice

The percentage of silica in igneous rocks varies in a systematic manner that parallels the abundance of other ________________.

elements

Continental collision, which result in mountain building cause some rocks to be uplifted while others are thrust downward, where _____ ____ and pressure trigger metamorphism

elevated temperatures

When a current experiences a rapid ___ loss, the largest particles settle first, followed by successively smaller grains.

energy

Animals that consume these plants or that consume other animals that eat plants use these organic compounds as a source of ____, and through the process of _____ , return carbon dioxide to the atmosphere.

energy respiration

The quantities of nonmetallic minerals used each year are

enormous

Instead, the existing atoms are rearranged into new crystalline structures that are more stable in the new _________________.

environment

The characteristic and extent of development of horizons vary in different _______________.

environments

Nonfoliated metamorphic rocks develop in environments where deformation is minimal and the parent rocks are composed of minerals that exhibit ______________ crystals, such as quartz or calcite.

equidimensional crystals

Southwestern Washington State, Mount Saint Helens ________________ with tremendous force.

erupted

lava

erupted magma

The cap rock halts the upwardly mobile oil and gas and keeps the oil and gas from ______________ at the surface.

escaping

Carbon also moves from the geosphere and hydrosphere to the atmosphere and back again.

ex: volcanic activity early in Earth's history is thought to be the source of much of the carbon dioxide found in the atmosphere.

Limestone is the most versatile and widely used rock of all is the best ____. As a building material is used not only as crushed rock and building stone but also in making ___.

example cement

flint

example of chert dark color results from the organic matter it contains

This is true of _____________magma in which the residual melt can become enriched in rare elements and some heavy metals

granitic

rhyolite is the _____________-grained equivalent of granite and, like granite, is composed essentially of the light-colored silicates. This fact accounts for its color, which is usually buff to ______________ or occasionally light gray.

fine pink

____________________(fine grained) texture: Igneous rocks that form at the surface or as small intrusive masses within the upper crust where cooling is relatively rapid exhibit a __________________ - ____________ texture termed ____________________

fine-grained texture aphanitic a = not phaner = not visible

Shale must exhibit the ability to split into thin layers along well-developed, closely spaced planes. This property is called __________.

fissility

The greatest volume of volcanic material is extruded from fractures in Earth's crust called ___________.

fissures

The optimum terrain for soil development is a _____to undulating upland surface. Good drainage minimum erosion sufficient infiltration of water into soil

flat

Mafic (basaltic) laves, which contain less silica are relatively ____________________and travel 90 miles before solidifying.

fluid

However, many composite cones also emit various amounts of __________ basaltic lava and occasionally, ___________________ material having felsic (rhyolitic) compositon.

fluid pyroclastic

The flanks of Mauna Loa have gentle slopes of only a few degrees. This low angle results cause very hot, ____________ lava traveled fast an far from the _____________.

fluid vent

Water dissolved in magma tends to increase _________________- because it reduces formation of long silicate chains by breaking silicon-oxygen bonds

fluidity

When rocks deep in the crust are subjected to compressional stress, like being placed in a giant vise, the entire mass may be deformed usually by ____.

folding

Because contact metamorphism does not involve directional stress, rocks found within a metamorphic aureole are not ___.

foliated

_______ rocks may be heated sufficiently to trigger _________.

gneissic rocks melting

By mapping the occurrences of index minerals, geologists can identify zones of varying metamorphic _________________.

grades

Start with clay-rich sedimentary rock such as shale or mudstone , there is a ________ increase in metamorphic intensity that is accompanied by a general __________________ of grain size.

gradual coarsening

Soil

gradually evolves to a state of equilibrium or balance with the environment.

In addition to quartz and feldspar, most ___________ rocks contain about ____% dark silicate minerals, usually biotite ________and __________. Granitic rocks are rich in silica (about ______%) and are the major constituent of the continental ______.

granitic 10% biotite mica and amphibole silica (70%) continental crust

Not all late-stage magmas produce pegmatites, nor do all have ___________________- compositions. Rather, some magmas become enriched in iron or copper.

granitic composition

The water for hydrothermal metamorphism can be _____ that has percolated down from the surface where it is heated and circulates upward. This type of metamorphism tends to occur at ____ pressure (shallow depth) and relatively low to moderate ________.

groundwater low temperature

Creating grassed waterways is another common practice. Natural drainage ways are shaped to form smooth, shallow channels and then planted with grass. The grass prevents the formation of __________ and traps soil washed from cropland.

gullies

These fountains are usually __________ and not associated with major explosive events that cause great loss of life and property.

harmless

These complex acids ___ the weathering process.

hasten

Thus, ________________ causes the ions to occupy more space, which in turn causes the _________ to expand. When the ions are vibrating rapidly enough to overcome the force of their chemical bonds, _______________ occurs. At this stage, the ions are able to slide past one another, and the orderly crystalline structure _______________.

heating solid melting disintegrates

Because water and other volatiles do not crystallize along with the bulk of the magma body, these fluids make up a ______ percentage of the melt during the final phase of solidification.

high

Much of the deformation associated with fault zones occurs at great depth and thus at _____ temperatures. In this environment, preexisting minerals deform by _______ flow.

high ductile

In some settings, _____________ temperature basaltic magmas reach Earth's surface, where they produce highly _____________ lavas.

high fluid

If melting continues, minerals with ________________ melting points begin to melt, and the composition of the melt steadily approaches the overall composition of the rock from which it was derived.

highest

During contact metamorphism of mudstones and shales, the clay minerals are baked, much like clay is baked in a kiln to make pottery. The result if a very hard, fine-grained metamorphic rock called ___.

hornfels Hornfels can form from a variety of other materials, including volcanic ash and basaltic rocks.

If the rocks that surround the pluton differ markedly in chemical composition from the invading fluids, there may be an exchange of ions between the fluids and the ___- rock.

host

When magma rises through the crust, it forcefully displaces preexisting crustal rocks referred to as _______________ _______________ or _______________ __________________.

host rock or country rock

When deeply buried magma bodies crystallize, the remaining volatiles collect as ___, ________-rich fluids that migrate through the surrounding rocks.

hot, water-rich These hot fluids play an important role in metamorphism and will be considered in chapter 8.

When hot, ion - rich water circulates through pore spaces or fractures in rock, a chemical alteration called _________________ ___________ may occur.

hydrothermal metamorphism

Water that drives hydrothermal metamorphism may also arise from _____ activity. As large magma bodies cool and solidify, ion-rich waters are driven into the surrounding host rocks. When the host rock is porous or highly fractured, mineral matter contained in these fluids may precipitate to form important deposits of __, __, and ___.

igneous copper, silver, and gold

Over time, these deformed rock masses are uplifted, and erosion removes the overlying material to expose the ______ and _____ core of the mountain range.

igneous and metamorphic

calcite mineral

image

chemical sedimentary rocks

image

chert

image

chlorite

image

earthworms in soils

image

facies of sediments

image

fault breccia

image

light nonferromagnesian silicates

image

lignite

image

limestone

image

marble

image

mechanical weathering

image

oil fossil fuels

image

olivine

image

oscillation ripple marks

image

photosynthesis

image

phyllite

image

potassium feldspar

image

pumice

image

pyroclastic

image

pyroclastic flow

image

pyroclastic flows

image

Workers in underground mines know that temperatures ______________ as one descends deeper below Earth's surface

increase

quartz

image

quartz sandstone

image

quartzite

image

residual soil

image

rills

image

Quartzite

image is a very hard metamorphic rock formed from quartz sandstone under moderate to high- grade metamorphism, the quartz grains in sandstone fuse together. The recrystallization is often so complete that, when broken, quartz splits across the original quartz grains rather than along their boundaries. In some instances, sedimentary features such as cross-bedding are preserved and give the rock a banded appearance. Pure quartzite is white, but iron oxide may produce reddish or pinkish stains, while dark mineral grains may impart shades of green or gray.

schist

image medium to coarse grained metamorphic rocks in which platy minerals are dominant these flat components include muscovite and biotite that display parallel alignments that give the rock its foliated texture quartz and feldspars some have amphiboles (dark minerals) parent rock is shale that has undergone medium-to high grade metamorphism

A large mass of magma may require thousands or even millions of years to solidify. Because different minerals crystallize under different environmental conditions (temperature and pressure), it is possible for crystals of mineral to become quite ______________ before others even begin to form. If molten rock containing some large crystals moves to a different environment --for example, by erupting at the surface --the remaining liquid portion of the lava cools more quickly. The resulting rock, which has large crystals embedded in a matrix of smaller crystals is said to have a _________________ texture.

image porphyritic texture

phyllite

image represents a degree of metamorphism between slate and schist constituent platy minerals are larger than those in slate but not large enough to be identifiable with unaided eye can be distinguished from slate by its glossy sheen and wavy surface exhibits rock cleavage and is composed mainly of very fine crystals of muscovite, chlorite , or both

rock or slaty cleavage

image rocks that split into thin slabs when hit with a hammer exhibit rock cleavage best displayed in slates that exhibit an excellent splitting property call slaty cleavage

Fossils

image the remains or traces of prehistoric life, are important inclusions in sediment and sedimentary rocks. important tools for interpreting the geologic past Knowing the nature of the life-forms that existed at a particular time helps researchers understand past environmental conditions. Fossils are important time indicators and play a key role in correlating rocks of similar ages that are from different places.

Pumice is a glassy volcanic rock with a _____________________ texture that forms when large amounts of _____________ escape through silica-rich lava to generate a gray, frothy mass. In some samples, the _____________ are quite noticeable, whereas in others the pumice resembles fine shards of ____________________ glass.

image vesicular gas voids intertwined

vesicular Common features of many extrusive rocks are the ______________ left by ______ bubbles that escape as lava solidifies. These nearly spherical openings are called ________________, and the rocks that contain them are said to have a ___________________ texture.

image voids gas vesicles vesicular

granite continued

image 10. granites appear gray in color from a distance 11. when composed of dark pink feldspar grains, granite can exhibit a reddish color.

halite

image chief component of rock salt used in cooking and seasoning of food melts ice on roads making hydrochloric acid sought, traded, and fought over in human history

conglomerate

image consists largely of gravels

Anphanitic is ______________grained.

image fine composed of crystals that are too small for the individual minerals to be identified without a microscope

when magma crystallizes at depth, it forms __________ ______________ __________ or _______________ rocks. These rocks are observed at the surface in locations where uplifting and erosion have stripped away the overlying rocks.

image intrusive igneous rocks or plutonic rocks, after Pluto, the god of the lower world in classical mythology.

chert

image is the name used for a number of very compact and hard rocks made of microcrystalline quartz

regolith

image layer of rock and mineral fragments produced by weathering. Some woudl call this soil, but soil is more than an accumulation of weathered debris.

Slate

image very -fined grained foliated rock composed of minute chlorite and mica flakes too small to be visible may contain quartz and feldspar crystals slate appears dull and resembles shale excellent rock cleavage or tendency to break into flat slabs generated by low-grade metamorphism of shale, mudstone, or siltstone also produced when volcanic ash is metamorphosed

texture of rock

image example

Giant's Causeway in Northern Ireland

image fig. 4.29

pegmatites

image of pegmatites

obsidian

image of rock

serpentinite

image of rock

iron oxide

image of rust

scoria

image of scoria

soil

image of soil

Yellowstone National park

image of the park

The existence of these high pressure chemical minerals provides convincing evidence that pressures and temperatures involved in ______ __________________ can be as great as those found in the upper mantle.

impact metamorphism

The products of these impacts, called _____________, include mixtures of fused fragmented rock plus glass-rich ejecta that resemble volcanic bombs.

impactiles

Where do gravels accumulate?

in a variety of environments indicate the existence of steep slopes or very turbulent currents.

Each event was followed by nearly a month of ____________________________.

inactivity

Graywacke

is associated with submarine deposits made by dense sediment-choked torrents called turbidity currents

using these _____ _____, geologists distinguish among different zones of regional metamorphism.

index minerals

Unlike most igneous rock names, such as granite and basalt, the terms tuff and volcanic breccia do not imply ________________ _____________. Instead, they are frequently identified with a modifier: for example, rhyolite tuff =

indicates a rock composed of ash - size particles having a felsic composition

A wide variety of resources are classified as ___ ___.

industrial minerals

The second major source of sediment is soluble material produced largely by chemical weathering. When these ions in solution are precipitated by either ____ or _____ processes, the material is known as chemical sediment, and the rocks formed from it are called ___ ____ rocks

inorganic or biological processes chemical sedimentary rocks

Across areas where regional metamorphism has occurred, rock textures vary based on the _________________ of metamorphism.

intensity

partial melting of mafic rocks yields ____________________ or ________________________ magmas.

intermediate or andesitic

The bands in the migmatites often form ___ ____ and may contain tabular ____ of the dark components.

intricate folds inclusions

19th century study by G.K. Gilbert of the U.S. Geological Survey in the Henry Mountains of Utah produced the first clear evidence that igneous _______________ can lift the sedimentary strata they penetrate

intrusions

The structures that result from the emplacement of magma into preexisting rocks are called ______________________ or __________________.

intrusions or plutons

Carbonic acid ionizes to form the reactive hydrogen ion and the bicarbonate ____.

ion

back carbonaceous slate contains organic material red slate get color from ____ green slate gets color from mineral ____

iron oxide chlorite

The element iron combines with oxygen to produce ___ ___

iron oxide, which give soil a reddish-brown or yellowing color.

So are major sources of ___, ___, _____, and ____ fertilizer, plus numerous materials essential to the construction industry, such as cement and aggregate.

iron, aluminum, manganese, phosphate

Regional metamorphism

is a common widespread type of metamorphism typically associated with mountain building, where large segments of Earth's crust are intensely deformed by the collision of two continental blocks. Sediments and crustal rocks that form the margins of the colliding continents are folded and faulted, and as a result, they shorten and thicken like a rumpled carpet. Continental collisions may also cause crystalline basement rocks, as well as slices of oceanic crust that once floored the intervening ocean basin, to be uplifted and deformed.

Sierra Nevada batholith

is a continuous granitic structure that forms much of Sierra Nevada in California

Hornfels

is a fine - grained nonfoliated metamorphic rock, and unlike marble and quartzite, it has a variable mineral composition.

black shale

is black because it contains abundant organic matter called carbon

pumice

is lighter in color and less dense than scoria, and many pumice fragments have so many vesicles that they are light enough to float

dolostone versus limestone

limestone with fizz with dilute HCl dolostone unless it is powdered will not visibly react to the acid

O horizon

largely organic material upper portion: plant litter, such as loose leaves and other organic debris lower portionL partly decomposed organic matter (humus) in which plant structures can no long be identified microscopic life: bacteria, fungi, algae and insects all organisms contribute oxygen, carbon dioxide and organic acids to the developing soil

Coast Mountains of western Canada into southern Alaska

larger batholith

lapilli

larger pyroclasts that range in size from small beads to walnuts; they are also called cinders

batholiths

largest intrusive igneous body occur as mammoth linear structures several hundred kilometers long and up to 60 miles wide ex: Sierra Nevada batholith

When molten rock reaches Earth's surface, it is called ________________.

lava

and bombs, when they are ejected as incandescent _____________

lava

Because cinder cones are composed of loose fragments rather than solid rock, the ___________ usually flows out from the uncosolidated base of the _______ rather than from the crater.

lava cone

Extrusive igneous rocks form when ____________ solidifies or when volcanic debris falls to ___________________ Surface.

lava Earth's

Rocks that exhibit a vesicular texture often form in the upper zone of a ___________ flow, where cooling occurs _______________ enough to preserve the _______________________ produced by the expanding gas bubbles.

lava rapidly openings

pahoehoe flows often dvelop cave-like tunnels called ________ _________, that were previously conduits for carrying lava from an active vent to the flow's leading edge

lava tubes

Recall that during high grade metamorphism, the light and dark components separate, given gneisses their characteristic banded or ____appearance.

layered thus most gneisses consists of alternating bands of white or reddish feldspar-rich zones and layers of dark ferromagnesian minerals These banded gneisses often exhibit evidence of deformation, including folds and sometimes faults

According to Bowen's reaction series, olivine crystallizes first and is _____ resistant to chemical weathering.

least

E horizon

light-colored layer that contains little organic material As water percolates downward through this zone, finer particles are carried away. washing of fine soil components is termed eluviation water percolating downward also dissolves soluble inorganic soil components and carries them to deeper zone. this depletion of soluble materials from the upper soil is termed leaching

formation of anthracite coal

lignite and bituminous coals are sedimentary rocks when sedimentary layers are subjected to the folding and deformation associated with mountain building, the heat and pressure cause a further loss of volatiles and water, thus increasing the concentration of fixed carbon

chert

like glass, it has conchoidal fracture its hardness, ease of chipping, and ability to hold a sharp edge made chert a favorite of Native Americans for fashioning points for spears and arrows

When the remaining melt solidifies --either in place or another location, if it migrates into fractures in the surrounding rocks--it will form a rock with a ___________________ much different from the _________________ __________________.

mineralogy parent magma

The most widespread occurrence of hydrothermal metamorphism is along the axis of the mid-ocean ridge system. As plates move apart, upwelling _____________ from the mantle generates new seafloor. As seawater percolates through the young, hot oceanic crust, it is heated and chemically reacts with the newly formed _____________ rocks. The result is the conversion of basaltic rocks of the oceanic crust and uppermost mantle into the hydrated rocks ___ and ___

magma basaltic serpentinite and soapstone

In some settings, deeply buried rocks become heating beyond their melting points, producing _____. When these magma bodies grow large enough to buoyantly, they __________________ the overlying metamorphic and sedimentary rocks.

magma intrude

Data of this type led them to examine the possibility that _____________ might change (evolve), and thus one magma body could become the _____________________ to a variety of igneous rocks.

magma parent

As a Large basaltic magma body cools, the heavy minerals that crystallize early tend to settle to the lower portion of the ________________ ___________________________

magma chamber

clay minerals

make up a high percentage of inorganic material in soils most abundant sedimentary rock, shale, contains a high proportion of clay minerals in picture is shale

When a rock undergoes partial melting, it forms a ____________ that is enriched in ions from minerals with the lowest melting temperatures, while the ________________ portion is composed of minerals with _________________ _____________ ______________.

melt unmelted highest melting temperatures.

These gases tend to separate from the _____________ as it moves toward the surface (from a high-to a low-pressure environment.

melt As the gases build up, they may eventually propel magma from the vent.

Liquid portion is called _____________, is composed mainly of mobile ions of the eight most common elements found in Earth's crust. 1. 2. 3. 4. 5. 6. 7. 8.

melt 1. silicon 2. oxygen 3. aluminum 4. potassium 5. calcium 6. sodium 7. iron 8. magnesium

Partial ________________ of basaltic rocks is yet another way in which at least some ____________________ magmas are produced.

melting andesitic

Thus, ______________ converts a ___________ consisting of tight, uniformly packed ions into a ________________ composed of unordered ions moving ___________ about.

melting solid liquid randomly

Many copper and silver deposits result when weathering processes concentrate _______________ that are dispersed through a low-grade primary ore.

metals

In Black Hills, _____________________ crystals as thick as telophone poles _____ feet have been

spodumene 40 feet

The altered rocks occur in a zone called a ___________ ____.

metamorphic aureole

The degree to which a parent rock changes during metamorphism is called its ___ ___.

metamorphic grade

There are many different environments in which ______ occurs. Most of these environments occur in the vicinity of plate margins, and several are associated with igneous activity.

metamorphism

In other words, these fluids bring in new atoms or take out atoms rather than simply reorganize what is already present. When this occurs, the overall chemical composition of the surrounding rock changes in a process called _______________.

metasomatism

Occasionally, these expanding gases propel incadescent lava hundreds of ____________ into the air, producing lava fountains.

meters

example: schists composed primarily of muscovite and biotite are called ____

mica schist

____, including ____, _____, and single-celled ___, play an active role in the decay of plant and animal remains.

microorgananisms fungi bacteria protozoa

Rocks of this type are called ______.

migmatites migma - mixture ite - stone

Crystallization in a fluid-rich environment, where ion ______________________ is enhanced, results in the formation of crystals several centimeters, or even a few meters, in length.

migration

Unlike the organic matter from which they formed, the newly created petroleum and natural gas are ____. These fluids gradually squeezed from the compacting mud-rich layers where they originate, called the _____ ____, into adjacent permeable beds such as __, where openings between sediment grains are larger.

mobile source rock sandstone

Soil water not only provides the necessary ______________ for the chemical reactions that sustain life, it also supplies plants with nutrients in a form they can use.

moisture

In addition, swelling of the magma chamber fractures the rock above, allowing the fluid magma to move upward along the newly formed openings often generating outpourings of lava for weeks, _____________ or years

months

Loss of gases renders magma (lava) ____________ viscous.

more

How many series?

more than 19,000

Quartz, which crystallizes last, is ______ resistant.

most

compaction of sediments

most common physical diagenetic change a reduction in pore space by packing grains more tightly together

Mt. Rainier, Washington

most dangerous volcano because like Nevado del Ruiz, it has thick, year-round mantle of snow and glacial ice 10,000 people live in the valleys around Rainer future rain could produce lahars that could be similarly destructive

Deep in the roots of _____, elevated temperatures caused by deep burial are responsible for the most intense metamorphic activity with a mountain belt.

mountains

At higher temperatures, flakes of _____ and ______ begin to dominate

muscovite and biotite

Certain microorganisms aid soil fertility because they have the ability to convert atmospheric nitrogen into soil___.

nitrogen

Inorganic limestones

occurs when chemical changes or high water temperatures increase the concentration of calcium carbonate to the point that it precipitates example: travertine ==type of limestone see in caves groundwater is the source of calcium carbonate

columnar jointing

occurs when igneous rocks cool and develop shrinkage fractures that produce elongated, pillar-like columns that move often have six sides

Lava has been intermittently pouring into the ______________________ever since, added new land to the island of _________________.

ocean Hawaii

Most active volcanoes on land are located along the margins of the _____ _____--notably within the _______ ________________ _____________known as the ___ ___ ____

ocean basins Circum-Pacific Belt "Ring of Fire"

The upper layers of the __________________--crust consist of basalt. In the United States, large portions of ________________ Oregon and ________________________ were the sites of extensive basaltic outpourings. These once -fluid basaltic flows have accumulated to thicknesses approaching ______ km or ____ miles

oceanic central Washington 3 km or 2 miles

Because this occurs in a marine environment, the rock layers containing the ___ and ___ are saturated with __.

oil and gas salt water

A geologic environment that allows for economically significant amounts of oil and gas to accumulate underground is termed an____ ___

oil trap

1500 of Earth's known volcanoes have erupted at least _______________, and some several times, in the past 10,000 years.

once

Once soil forms, erosional forces, especially water and wind, move soil components from ___ place to another

one

Unlike confining pressure, which squeezes rock equally in all directions, differential stresses are greater in ____ direction than in others.

one

frost wedging

one important example from mechanical weathering is that the frequency of freeze-thaw cycles greatly affects the amount of _ ____.

anticline as oil trap

one of the simplest traps, is an uparched series of sedimentary strata rising oil and gas collect at the top of the fold

B horizon

or subsoil is where much of the material removed from the E horizon by eluviation is deposited zone of accumulation accumulation of the fine clay particles enhances water retention in the subsoil in extreme cases clay accumulation forms a very compact and impermeable layer called hardpan

In some environments, ions may actually migrate into or out of a rock, thereby changing its ______ chemical composition.

overall

biosphere

owes its existence to a dozen or so elements that must ultimately come from Earth's crust

The abundant element in earth's crust is _____________. It makes up 47 % of Earth's crust by weight and _____% by volume.

oxygen 94% Oxygen atoms are so much bigger than most other atoms in common minerals that Earth's crust is mainly atoms packed closely together with smaller atoms , such as silicon, aluminum, potassium, tucked in between.

fig. 4.19 Water lowers the melting temperature of hot mantle rock to trigger _______________ melting. As an oceanic plate descends into the mantle, water and other volatiles are driven from the subducting crustal rocks into the mantle above.

partial melting

Experiments show that under the high pressure conditions calculated for the upper mantle, ______________ ______________ of the ultramafic peridotite yields a magma of _______________ composition.

partial melting basaltic

Because of this unique position, sediments and the rock layers that they eventually form contain evidence of ____ conditions and events at the surface.

past Furthermore, sedimentary rocks contain fossils, which are vital tools in the study of the geologic past.

The resulting rocks, called ______________ are composed of these unusually large crystals.

pegmatites

Partial melting of the mantle rock _____________ generates hot basaltic magma whose temperatures may exceed 1250 C or 2300F

peridotite

____________________is coarse grained texture. When large masses of magma slowly crystallize at great depth, they form igneous rocks that exhibit a coarse-grained texture described as phaneritic. Coarse grained rocks consists of a mass of _______________ crystals that are roughly equal in size and ______________ enough so the the individual minerals can be _____________________- with the aid of a _____________________. Geologists often use a small magnifying _________ to aid in identifying minerals in a phaneritic rock.

phaneritic phaner = visible intergrown large identified microscope lens

The large crystals in porphyritic rocks are referred to as __________________________, whereas the matrix of smaller crystals is called ___________________________.

phenocrysts (pheno = sho) (cryst = crystals) groundmass

Through the process of ____, plants absorb carbon dioxide from the atmosphere to produce the essential organic compounds needed for growth.

photosynthesis

Slate forms _______

phyllite, through continued recrystallization, generates a medium-grained schist.

As long as precipitation was adequate, the soil remained in ___.

place

Andesite commonly exhibits a porphyritic texture. The phenocrysts are often light, rectangular crystals of _____________________- feldspar or black, elongated __________________ crystals. Andesite may resemble _________________, so its identification usually requires microscopic examination to verify mineral makeup.

plagioclase amphibole rhyolite

Coal is formed mostly from ___material that accumulated in swampy environments on land

plant

Climatic conditions are an important control on the type of ___ and ____ life present.

plant and animal

The primary source of organic matter in soil is ___, although ____ and an infinite number of ____ also contribute.

plants animals microorganisms

The basic connection between plate tectonics and volcanism is that ___

plate motions provide the mechanisms by which mantle rocks undergo partial melting to generate magma

The crystals that make up aphanitic rocks are so small that individual minerals can be distinguished only with the aid of a ____________________ microscope or other techniques. Therefore, we commonly characterize fine -grained rocks as being _______________, ___________________, or _____________- in color. Light -colored aphanitic rocks are those containing primarily light-colored _________________________ silicate minerals

polarizing light, intermediate dark nonferromagnesian

Humans can influence the rate of weathering by producing _______ that alter the composition of the atmosphere. ex: acid rain

pollutants

graywacke continued

poor sorting and angular grains characteristic of graywacke suggests that particles were transported only relatively short distance from their source area and were then rapidly deposited. Before the sediment could be reworked and sorted further, it was buried by additional layers of material.

On steep slopes, soils are ___ developed. Moisture content of the soil may not be sufficient for vigorous plant growth.

poorly

If the rock contains mixed large and small particles, the sand is said to be ___________ ____________.

poorly sorted

The remaining half consists of ____ spaces among the solid particles where air and water circulate.

pore

The addition of cement into a sedimentary deposit reduces the _____ as well.

porosity

Several geologic structures may act as oil traps, all have two basic features: 1. _______________________________ _______________ 2. ___ ____

porous permeable reservoir rock that will yield petroleum and natural gas in sufficient quantities to make drilling worthwhile 2. cap rock, such as shale, that is virtually impermeable to oil and gas

Metamorphic rocks may also contain some unusually large grains, called _________________, that are surrounded by a fine-grained matrix of other minerals.

porphyroblasts

A rock with a porphyritic texture is termed a ____________________.

porphyry

Amount of ______ influences the degree to which various materials are removed from the soil by percolating waters (a process called ____) and thereby affecting soil fertility.

precipitation leaching

Variations in temperature and precipitation determine whether chemical or mechanical weathering will _____ and also greatly influence the rate and depth of weathering.

predominate

By contrast, metamorphic rocks that contain platy minerals (such as micas) and or elongated minerals (such as amphiboles) typically display some kind of _____ orientation in which the mineral grains exhibit a parallel to subparallel alignment

preferred

Although the proportion of the major components in soil vary, the same four components are always _______to some extent

present

Partial melting that produces mantle-derived magmas may be triggered by a reduction in confining ________________________ during the process of __________________________ melting. this can occur, for example, where hot mantle rock ascends as part of slow-moving convective flow at mid-ocean ridges.

pressure decompression

Each type of metamorphism occurs over a range of temperatures and ____

pressures.

Basaltic (mafic ) magmas that originate from partial melting of mantle rocks are called ___________________ or ___________________ magmas because they have not yet evolved.

primary or primitive

organic

processes of water-dwelling organisms also form other chemical sediments are said to be biochemical ex: many water - dwelling animals and plants extract dissolved mineral matter to form shells and other hard parts after the organisms die, their skeletons collect by the millions on the floor of a lake or an ocean as biochemical sediment

inorganic

processes such as evaporation and chemical activity can produce chemical sediments example: dripstone that decorates many caves ex: salt left behind as a body of seawater evaporates

diatoms and radiolarians

produce glasslike silica skeletons tiny organisms are able to extract silica even though seawater contains only tiny quantities it is from their remains that most bedded cherts are believed to originate some bedded cherts occur in association with lava flows and layers of volcanic ash the silica came from the decomposition of the volcanic ash and not from biochemical sources

Acids such as carbonic acid readily decompose many rocks and produce certain ______ that are soluble in water.

products

Upon impact, the energy of the once rapidly meteorite ( fragments of comets or asteroids) is transformed into heat energy and shock waves that pass through the surrounding rocks. The result is _____, _____ and sometimes melted rock.

pulverized, shattered

Because of large percentage of voids, many samples of _________________ float when placed in water. Oftentimes, flow lines are visible in pumice, indicating that some movement occurred before solidification was ___________________.

pumice complete

Another common vesicular rock, called __________________-, forms when ________-rich lava is ejected during an explosive eruption.

pumice silica

________________________ (fragmental) texture is another group of igneous rocks is formed from the consolidation of individual rock fragments ejected during explosive volcanic eruptions. The ejected particles might be very fine ash, molten blobs, or large angular blocks torn from the wall of a vent during an _____________________. Igneous rocks composed of these rock fragments are said to have a ________________________ or ___________________ texture.

pyroclastic eruption pyroclastic texture or fragmental

Some of the most destructive forces of nature are ____________ _____________, which consist of hot gases infused with incandescent ash and large lava fragments.

pyroclastic flows

When volcanoes erupt energetically, they eject pulverized rock, lava, and glass fragments from the vent. The particles produced are called ________________ ______________.

pyroclastic materials

The light colored silicates, usually ______ and ____ ____ have the lowest melting temperature and begin to melt first.

quartz potassium feldspar

For example, when quartz sandstone is metamorphosed to form _______, the mineralogy does not change; the quartz remain quartz.

quartzite

In addition, quartz sandstone is metamorphosed to produce

quartzite

During some volcanic eruptions, molten rock is ejected into the atmosphere, where it is _________________ and _____________ quickly to become a solid. Rapid cooling of this type may generate rocks having a _____________________ texture.

quenched cools glassy

One hazard associated with volcanoes is their ability to produce ________________

tsunamis

When the parent material is bedrock, the soils are termed

residual soil

Headstones of granite, which is composed of silicate minerals, are relatively _____ to chemical weathering.

resistant

Quartz, the other main component of granite is very ______ to chemical weathering; it remains substantially unaltered when attacked by weak acidic solution

resistant

Soil conservation programs can substantially reduce the loss of this basic _____.

resource

Andesites and other lavas of intermediate composition account for most of the ________.

rest

Gneisses having a felsic composition may be derived from granite or its fine grained equivalent, ____.

rhyolite

In contrast to granite, which is widely distributed as large intrusive masses, _______________ deposits are ________________ common and generally less voluminous. The thick rhyolite lava flows and extensive ash deposits in and around _____________________ _____________ _______________ are well known exceptions to this generalization.

rhyolite less Yellowstone National Park

When normal farm cultivation cannot eliminate the channels, we know the _______ have grown large enough to be called _____

rills gullies

Other features found in some sedimentary rocks also give clues to the past. ____ ______ are small waves of sand that develop on the surface of a sediment layer through the action of moving water or air.

ripple marks

Water causes _______ to melt at _________________ temperatures, just as putting rock salt on an icy sidewalk induces melting.

rock lower

Many factors influence the rate of rock weathering. Among the most important are variations in the composition of the ____. More resistant rock protrudes as ____ or as steeper _____ on an irregular hillside.

rock ridges cliffs

What can geologists infer from the texture?

rock's origin based on careful observations of grain size and other characteristics of the rock

The incomplete melting of ___________ is known as ________________________ ______________ a process that produces most magma.

rocks partial melting

Oil and gas, being less dense than water, migrate upward through the water-filled pore spaces of the enclosing ___.

rocks.

These nearly flat, step-like surfaces slow ______ and thus decrease soil loss while allowing more water to soak into the ground.

runoff

conduit in volcano

tube where magma comes up through

Such a transformation is often termed ____________ _________ and takes place in one or two ways. 1. 2.

secondary enrichment 1. chemical weathering coupled with down-ward percolating water removes undesired materials from decomposing rock, leaving the desired element in the upper zones of the soil. 2. basically the reverse of the first; the desirable elements that are found in low concentrations near the surface are removed and carried to lower zones, where they are redeposited and become more concentrated.

Once in the stream channel, these soil particles, which can now be called _____, are transported downstream and eventually deposited.

sediment

nevertheless, most of the Earth's solid surface consists of either _____ or ___________________!

sediment sedimentary rocks

Over a broad area, erosion caused by surface runoff may be estimated by determining the ___ __ of the streams that drain the region.

sediment loads

Not all dead plant material decays immediately back to carbon dioxide. A small percentage is deposited as sediment. Over long spans of geologic time, considerable biomass is buried with ____.

sediment.

___rocks are important in the interpretation of Earth history

sedimentary

Other types of pyroclastic rocks are composed of fragments that solidified before impact and became cemented together at some later time. Because pyroclastic rocks are made of individual particles or fragments rather than interlocking crystals, their textures often resemble those exhibited by _________________ rocks rather than those associated with ________________ rocks

sedimentary igneous

A thin veneer of _______________ rock and a small iron-________core plus igneous and metamorphic rocks make up the Earth.

sedimentary rich

Some of these bodies cut across existing structures, such as _____________________ strata, wheras others form when magma is injected between ______________________________ layers.

sedimentary sedimentary

An environment of deposition or ____________________________ ___________ is a geographic setting where sediment is accumulating.

sedimentary environment

5. As deposition continues, older sediments are buried beneath younger layers and gradually converted to ___ ___

sedimentary rock (lithified) by compaction and cementation -this and other changes are referred to as diagenesis, a collective term for all the changes (short of metamorphosis) that take place in texture, composition, and other physical properties after sediments are deposited

Shale

sedimentary rock consisting of silt and clay size particles account for over half of all sedimentary rocks particles in these rocks are so small that they cannot be readily identified without great magnification and this makes shale more difficult to study and analyze than other sedimentary rocks

When the organisms die, these skeletal remains settle to the ocean floor as biochemical sediment and become ____ ___.

sedimentary rock.

bedding planes

separate the strata or beds these are relatively flat surfaces along which rocks tend to separate or break changes in the grain size or in the composition of the sediment being deposited can create bedding planes pauses in deposition can also lead to layering because chances are slight that newly deposited material will be exactly the same as previously deposited sediment

In the Grand Canyon, where the gentler slopes of weathered ____ are quite inconspicuous and overgrown with vegetation, in contrast with the bold cliffs produced by more durable rocks.

shale

the parent rock of most hornfels is_____ or another clay-rich rock, which has been "baked" by a hot intruding magma body.

shale Hornfels tend to be gray to black in color and quite hard, and it may display conchoidal fracture.

With the exception of the volcanic islands that form above subduction zones, most other small oceanic islands are either a single _________________ volcano or the coalescence of two or more shields built on massive amounts of pillow lavas

shield

Recall that heat from the hot basaltic magma can partially melt the overlying crustal rocks, which are ______________ rich and have a much lower melting temperature, thereby producing large quantities of granitic magmas.

silica This process is thought to have been responsible for the volcanic activity in and around Yellowstone National Park in the distant past

By contrast, rocks high in _________ contain very little iron, magnesium or calcium, but are enriched with _____________ and __________.

silica enriched with sodium and potassium

Separation of these two fractions yields a melt with a chemical composition that is richer in ____________________ and nearer the _____________ granitic end of the spectrum than the rock from which it formed.

silica felsic (granitic)

Granitic magma, which as a high _______________ content, is quite ______________ "thick" and may erupt at temperatures as low as _____________________.

silica viscous 650 C or 1200F

_______________ - rich magmas erupt mainly along the continental margins.

silica - rich. This is strong evidence that continental crust, which is thicker and has a lower density that oceanic crust, must play a role in generating these more highly evolved magmas.

Composiste cones reflect the viscous nature of the material from which they are made. In general, composite cones are the product of _____________ - ___________ magna having an __________________________composition.

silica -rich andesitic

Although aluminum is the third most abundant element in Earth's crust, economically valuable concentrations of this important metal are not common because most aluminum is tied up in _____ minerals, from which is extremely difficult to extract.

silicate

Igneous rocks are composed mainly of _________________ minerals.

silicate

When magma cools, generally the _____________ and __________ atoms link together first to form_____________________________, the basic building blocks of the silicate minerals.

silicon and oxygen silicon-oxygen tetrahedra

What are the two most abundant constituents of igneous rocks? Name the other elements that when combined with Si and O comprise 98% by weight of most magmas. Magmas contain small amounts of many other elements like________________ and _______________ plus trace amounts of much rarer elements like ____________ , _________ and ____________.

silicon and oxygen 1. aluminum 2. calcium 3. sodium 4. potassium 5. magnesium 6. iron titanium and manganese gold, silver, and uranium

At temperatures approaching the melting point of rock, ____ forms. Sillimanite is a high-temperature metamorphic mineral used to make porcelains used in extreme environments, such as for spark plugs.

sillimanite

By contrast, the mineral ___ forms only in extreme environments, where temperatures exceed ______F and rocks containing it _____ - grade.

sillimanite 1100 F high - grade

Most cinder cones are produced by a ___________, short-lived eruptive event.

single

texture is used to describe the ____, ____, and arrangement of the mineral grains within a rock.

size shape and mineral grains

In addition, most of the lava (80%) flowed through a well-developed system of lava _____

tubes

By contrast, minerals such as muscovite and biotite typically form a large number of ________ grains. As a result, metamorphic rocks that contain large crystals (porphyroblast) for example, garnet embedded in a finer-grained matrix of biotite and muscovite are common.

smaller

stocks

smaller plutons are termed stocks

Gradually, sharp edges and corners become ________ and ___________.

smooth and rounded

pahoehoe

smooth surfaces that sometimes resemble twisted braids hotter and more fluid pahoehoe can change into aa lavas

chalk

soft, porous rock made up almost entirely of the hard parts of microscopic marine organisms found along the southeast coast of England

Although thinly distributed over the land surface, the _____ functions as a fundamental interface, providing and excellent example of the integration among many parts of the Earth system

soil

thinnest veneer of _____ combine to support a web of life of wondrous diversity in continous change

soil

Inf fact, for well-developed soils in many regions, the significance of natural vegetation in influencing ___ type is frequently implied in the description used by soil scientists. 1. 2. 3.

soil 1. prairie soil 2. forest soil 3. tundra soil

When the environmental changes occur, such as climate, vegetative cover, and animal (including human) activity, the

soil responds

during metamorphism, the rock remains essentially ____.

solid

The Earth's crust and mantle are composed primarily of _______________ not, molten, rock. Although the outer core is ____________, this iron-rich material is very ___________ and remains deep within Earth.

solid fluid dense

To better understand how magma crystallizes, let us consider how a simple crystalline ________melts. Recall that, in any crystalline solid, the ____________ are arranged in a closely packed regular pattern. However, they are not without some motion: they exhibit a restricted vibration about fixed points.

solid ions

Most magma originates in rocks from Earth's upper mantle that is essentially

solid, not molten

igneous rock forms as molten rock cools and __________________.

solidifies.

The felsic (granitic) magmas produced in this manner usually __________________ before reaching the surface, so volcanism is not typically associated with these collision - type mountain belts.

solidify

Soil water is far from pure water, instead, it is a complex solution that contains many ____ _____.

soluble nutrients

immature

some soils lack horizons altogether soil building has been going on for only a short time characteristic of steep slopes, where erosion continually strips away the soil, preventing full development

Deposits of wind-blown sand are usually better ____ than deposits sorted by wave activity.

sorted

mineral silvite

source of potassium "potash" fertilizer

parent material

source of the weathered mineral matter from which soils develop and is a major factor influencing newly forming soil

The most productive kimberlite pipes are those in

south Africa

Eventually, an angular block may evolve into a nearly ____ boulder.

spherical

Once this occurs, the boulder's shape does not change, but the ____ mass continues to get smaller.

spherical

what does texture reveal?

the environment in which the rock formed

The more viscous the material

the greater its resistance to flow ex: syrup is more viscous than water

potassium feldspar

the most abundant products of the chemical breakdown of feldspar are residual clay minerals

cementation

the most important process by which sediments are converted to sedimentary rock it is a change that involves the crystallization of minerals among the individual sediment grains gradually, the crystallization of new minerals from these ions takes place in the pore spaces, cementing the clasts together

The names of the classificaiton units are combinations of syllables, most of which are derived from Latin or Greek

the names are descriptive ex: aridosol Latin aridus - dry solum - soil are characteristically dry soils in arid regions inceptisol inceptum = beginning solum = soil are soils with only the beginning or inception, of profile development

conglomerates

the particles are large enough to be identified as distinctive rock types; thus, they can be valuable in identifying the source areas of sediments poorly sorted because the opening between the large gravel particles is sand or mud

Bauxite

the principle ore of aluminum is one important example of an ore created as a result of enrichment by weathering processes

Lithification

the processes by which unconsolidated sediments are transformed into solid sedimentary rocks. lithos = stone fic = making

strata or beds

the single most common and characteristic of sedimentary rocks each straum is unique it may be sandstone, a fossil-rich limestone, a black shale, the variations in texture, composition, and thickness reflect the different conditions under which each layer was deposited. thickness of beds ranges from microscopically thin to tens of meters thick.

magma

the source material for volcanic eruptions is _______, molten rock that usually contains some crystals and varying amounts of dissolved gas

crystal settling

this process occurs when the earlier formed minerals and denser (heavier) than the liquid portion and sink toward the bottom of the magma chamber

fault trap

this type of trap forms when strata are displaced in such a manner as to bring a dipping reservoir rock into position opposite an impermeable bed

There are ____ foliated textures

three 1. rock or slaty cleavage 2. schistosity 3. gneissic texture or banding

By applying a thorough knowledge of present-day conditions, geologists attempt to reconstruct the ancient environments and geographic relationships of an area at the ___ a particular set of sedimentary layers were deposited.

time

schist describes the texture of rocks and as such it is used to name rocks that have a wide variety of chemical compositions

to indicate composition, mineral names are added.

No single factor is responsible for a soil's character; rather it is the combined influence of parent material, time, climate, plants and animals, and ____ that determines this character.

topography

The lay of the land can vary greatly over short distances. Variations in ____ can lead to the development of a variety of localized soil types.

topography

By contrast, those developed on unconsolidated sediment are called ____ soils.

transported

Frequently, crop residues are left on fields. This debris protects the surface from both water and wind erosion. To protect fields from excessive wind erosion, rows of _____ and shrubs are planted as windbreaks that slow the wind and deflect it upward.

trees

Pyroclastic Rocks are composed of fragments ejected during a ________________ eruption. One of the most common pyroclastic rocks called _______________, is composed of many tiny, ash-sized fragments that were later cemented together. In situations where the ash particles remained hot enough to fuse, the rock is called _______________ _________________. Welded tuff consists of tiny glass shards, it may contain walnut size pieces of ___________________ and other rock fragments

volcanic tuff welded tuff pumice

Cinder cones number in the thousands around the globe. Some occur in groups such as the ____________________ field near _________________, Arizona

volcanic field Flagstaff, Arizona

Geologists have observed that, over time, a ______________ may extrude lavas that vary in ________________________.

volcano composition

The lava flows generally form in the final stages of the ___________________ life span, when the magma body has lost most of its gas content.

volcano's

these destructive sea waves sometimes result from powerful volcanic explosions or the sudden collapse of flanks of _________________ into the ocean.

volcanoes 1883, volcanic eruption on the Indonesian island krakatoa tore the island apart and generated a tsunami that killed 36,000

At temps that exceed 2000 F, these gases can quickly expand to occupy hundreds of times their original ______________________.

volumes

When a prolonged drought struck in the 1930's, the unprotected soils were _____ to the wind. Severe soil loss, crop failure, and economic hardship resulted.

vulnerable

The optimal environment for chemical weathing is a combinations of ____ temperatures and abundant __.

warm moisture

eluviation

washing out of fine soil components

Another factor affecting the melting temperature of rock is its ____ content.

water

Basaltic magmas are also generated at subduction zones, where __________ driven from the descending slab of oceanic crust promotes partial melting of the mantle rocks that lie above.

water

One way that carbon dioxide makes its way back to the hydrosphere and then to the solid Earth is by first combining with ____ to form carbonic acid (H2CO3), which then attacks the rocks that compose Earth's crust.

water

The 3 remaining elements aluminum silicon oxygen join with ________________ to produce residual clay minerals.

water

The salt dissolves in water and seeps into cracks that quite likely originated from frost action. When the _______ evaporates, the growth of salt crystals further breaks the pavement

water

Water is abundant in Earth's crust. In the upper crust ____ occurs as groundwater.

water

thinner film of

water

The introduction of ___________ to generate magma occurs mainly at ____________________ plate boundaries, where cool slabs of oceanic lithosphere descend into the mantle.

water convergent

lahars occur when volcanic ash and debris becomes saturated with ____________ and rapidly moves down steep volcanic slopes, generally following stream valleys.

water 1. Mt. St. Helens 2. 1985, deadly lahars during eruption of Nevado del Ruiz in the Andes mountains of columbia claimed 25,000 lives

When present in solid rock, they may be used to determine the direction of movement of ancient wind or ___ ____.

water currents