geology mid exam

Modern plate tectonic theory was developed in what decade?

1960s

As the map below shows, the oldest seafloor is generally less than 200 million years old. Why?

All oceanic lithosphere eventually gets subducted beneath the continents by the time it is 200 million years old.

Sort each of the following metamorphic rocks according to its protolith.​​​​​​

limestone: marble mudstone: schist & phyllite sandstone: quartzite conglomerate: metaconglomerate

Coal is a sedimentary rock that forms from

plant remains

The various geologic settings in which rocks can melt, metamorphose, or become sediment are ultimately generated by

plate tectonics

Which of the following processes can be responsible for the development of compositional banding?

segregation of minerals into bands of different composition compositional differences in the protolith that are stretched and smeared out

Label the block diagram of the lithosphere appropriately.

bottom to top: - asthenospheric mantle - lithosphere - moho - continental crust - oceanic crust

Intrusive igneous rocks

cool slowly and are coarse-grained.

When magma or melt solidifies it forms _______ rocks. If a pre-existing rock is exposed to extreme heat or pressure its physical properties can change, forming a(n) ___________ rock. Rocks derived from the weathered grains of other pre-existing rocks through lithification are _________ rocks.

igneous metamorphic sedimentary

A clastic sedimentary rock with clay and silt-sized grains that is finely laminated and breaks into thin sheets is called

shale

Label the soil horizons on the image below.

top to bottom: - contains abundant organic material - organic material mixed with clay, silt, and sand - abundant leaching, little organic matter - clay and fine organics collect to form new minerals - weathered bedrock - intact bedrock

Which of the following statements about hardness is true?

A copper penny will scratch gypsum.

compression

A force that pushes on or squeezes a material.

convergent boundary

A plate boundary where two plates move toward each other. SUBDUCTION

crystal

A single, continuous piece of a crystalline solid typically bounded by flat crystal faces - shaped like cubes, prisms, blades, and pyramids

Identify the true statement. Choose one: A. Spheroidal weathering is due to faster rates of weathering along corners and edges of a rock. B. All of the possible answers are correct. C. Chemical weathering is fastest where surface area is low. D. Weathering happens fastest on the flat faces of broken blocks of rock.

All of the possible answers are correct.

Obsidian is a volcanic glass that forms when lava cools very quickly and consists of a solid mass of glass through and through. Why is obsidian not classified as a mineral? Choose one:

The atoms or molecules in obsidian do not have a crystalline structure.

Which of the following statements about differentiation are true?

The mantle formed as a result of differentiation. The core formed as a result of differentiation.

What would be the significance of finding a precipitated mineral on another planet?

The planet may have or have had liquid water on it.

Why are there so many different types of magma?

The source rock from which magmas form may differ. Different magmas may mix to form a new magma.

As clastic sediment is transported downstream, away from its point of origin, what happens to the clasts?

They become smaller in size.

The Himalayas are growing because

a continental plate is colliding with another continental plate there.

The feature that may form where a stream enters a lake or ocean is called

a delta.

A mineral is to a rock as

an atom is to a molecule.

Pillow basalts

are formed in a submarine environment.

The classification of igneous rocks depends on both grain size and silica composition. Using your knowledge of this information for the igneous rocks listed, place the rock names in the correct positions on the chart.

basalt: fine, mafic diorite: fine, intermediate gabbro: fine, mafic peridotite: coarse, ultramafic rhyolite: fine, felsic

Wegener's theory of continental drift took decades to be accepted

because Wegener couldn't explain how continents moved.

Shale, a sedimentary rock, can be metamorphosed to schist through

burial during continental collision.

factors that cause metamorphism

change in pressure, temperature, fluids, stress

shear

changes the angle of a shape

minerals are identified by

color, streak, luster, hardness, cleavage, fracture tendency

the two polymorphs of carbon are

diamond and graphite: the hardest and softest minerals, result of different atomic bonds

mineral identification

effervescence- reactivity with acid (calcite) magnetism- magnetic attraction (magnetite) taste smell

characteristics of intrusive igneous bodies

features like stocks, laccoliths, sills, and dikes are formed

Determine whether the rock is felsic, intermediate, mafic, or ultramafic.

felsic

Sort the images of rocks below into the three different categories of rocks. (THREE MAJOR ROCK GROUPS)

igneous (volcanic & marbled rock-- extrusive, small crystals) sedimentary (rocks & cliffs) metamorphic (form/pattern changing)

Cite factors that can result in metamorphism.

increased temperature increased pressure hydrothermal fluids

physical interior of the earth (modern)

inner core, outer core, mesosphere, asthenosphere, lithosphere

The crystallization of salt from evaporating seawater

is an example of precipitation from a solution.

The boundary between the lithosphere and the asthenosphere

is the boundary between rigid mantle and plastic mantle.

Match the following geologic settings to the form of metamorphism which occurs at that location.

mid-ocean ridge: hydrothermal mountain range core: dynamol-thermal ten miles below the surface: burial fault zone: dynamic Intrusion of pluton: thermal meteorite impact site: shock

Label the atoms in the silica-oxygen tetrahedron shown in the image below

middle: silicon red balls: oxygen

Identify outcomes of physical weathering. Choose one or more: A. clay minerals B. more rounded fragments C. chemically altered minerals D. smaller fragments

more rounded fragments smaller fragments

silicates

most abundant mineral family & most rock forming mineral group - oxygen and silicon (46, 27%) - silicate minerals are by far the most dominant substances comprising earth's crust and mantle - silicate minerals with isolated tetra. do not share any oxygens

Which of the following sedimentary structures indicates that the sediments were deposited by a moving fluid?

ripple marks

The genetic scheme for classifying rocks is based on

the origin of formation.

cleavage

the tendency of a mineral to break along lattice planes with weaker atomic bonds - can be distinguished from crystal faces because it is through-going ; faces are on external surfaces only

The global occurrence of earthquakes reveals that

they usually occur on the boundaries of plates or at hot spots.

metamorphic rocks definition

those that result from solid-state alteration of preexisting rocks

The heavier elements on the Earth (those with atomic numbers greater than 5)

were formed by stellar nucleosynthesis during the life cycles of older stars and supernovae.

Place in chronological order the events that led to the formation of the Earth.

1) The Earth cleared its orbit of all other matter, making it a true planet. 2) The Moon formed. 3) Volcanic activity occurred, releasing gases. 4) An atmosphere formed.

Place in chronological order the events that led to life as we know it on Earth.

1) The oceans formed. 2) Photosynthetic organisms appeared on Earth. 3) Oxygen (O2) accumulated in the atmosphere. 4) Multicellular life developed rapidly on Earth.

mineral

- naturally occurring - inorganic solid - crystalline structure (exception is lacking internal atomic order: glasses) - formed by geologic processes - definite chemical composition

Order the steps that lead to assimilation.

1) A magma forms and begins to migrate through the crust. 2) Blocks of the surrounding silica-rich crust break off and become incorporated into the magma. 3) Incorporated crustal blocks within the magma melt, mixing with the magma. 4) The amount of silica in the magma increases and the magma composition changes accordingly.

Order the events chronologically that occurred in the formation of our Solar System.

1) An accretionary disk formed. 2) A protosun formed. 3) Rings formed in the protoplanetary disk. 4) Planetesimals collected to the protoplanets.

Identify statements true of Pangaea. Choose one or more:

Pangaea was one of several supercontinents that have formed and broken up during Earth's history. Rates of seafloor spreading in the Atlantic Ocean are compatible with what is known about the breakup of Pangaea. The regional-scale folds visible in the Appalachian Mountains are remnants of Pangaea's formation.

Sort outcomes of continental collision versus those related to ocean-ocean (oceanic) convergence.

continental collision: - crustal thickening - mountain building oceanic convergence: - subduction - volcanism

Identify the four tectonic settings of igneous activity.

continental rift, hot-spot volcano, mid-ocean ridge, subduction zone

Which of the following methods of heat transfer occurs when an increase in temperature creates a decrease in density, causing the warm, less dense material to rise, as shown in this diagram?

convection

chemical interior of the earth (classical)

core, mantle, crust

Drag and drop the mineral names to the correct position on this graph of the Mohs hardness scale. (Note that in this graph the actual hardness is plotted on the vertical axis.)

diamond: highest talc: lowest

As magma cools and minerals begin to form, the composition of the resulting magma becomes more

felsic.

Wegner's evidence for continental drift

fit of continents, locations of past glaciations and past tropical regions, distribution of fossils, continuity of geologic units and mountain belts between continents

classifying clastic sedimentary rocks

grain size and texture, mineralogy and texture

The hardness of a mineral is determined by

its ability to resist being scratched by other substances.

The Earth is round because

its interior rock is warm enough to flow slowly in response to gravity.

In which tectonic setting would you most expect to find igneous activity?

landward of oceanic trenches

Drag the appropriate labels to the geological features on the map below. Keep in mind that the darker blues represent deeper water.

left to right: - fracture zone - abyssal plain - continental shelf - mid-ocean ridge

Label the image with the features of tectonic plates.

left to right: - moho - continent - continental crust - continental shelf - lithospheric mantle - asthenosphere - abyssal plain - oceanic crust

Label each target on the map below with the name of the appropriate geological feature.

left to right: - mountain belt - ice sheet - continental shelf - plain

Which of the following features is a bed-surface marking, meaning that it appears on the surface of a bed as a result of events during or soon after sediment deposition?

mud cracks

Biogenic minerals are minerals produced by living organisms. Two commonly seen biogenic minerals are _____________, which is often produced by coral and other invertebrates, and ____________, which often makes up the shell material of mollusks such as clams.

aragonite calcite

After an explosive volcanic eruption on an island, the surrounding sea is full of light-gray, floating rock. What must it be?

pumice

Which of the following terms has to do with extrusive igneous activity?

pyroclastic

When you scrape a mineral along a ceramic plate to observe the color of its powder, you are checking the physical property known as

streak

inclination

- the angle between the earth's surface and the magnetic field line - towards magnetic pole

Steps to create a sedimentary rock

- weathering - erosion (removal of grains) - transportation - deposition (transp. of fluids) - lithification (transformation fo solid rock)

Order the steps in neocrystallization.

1) Protolith minerals are consumed by chemical reactions. 2) Thin clay minerals begin to align. 3) Clay grains flatten out and become parallel to one another. 4) Small garnets appear.

Order the steps in the weathering process, starting with a solid rock, such as granite.

1) coherent, unweathered rock 2) chemical weathering weakens rock 3) rock breaks apart into loose grains 4) regolith and clay form

The early view of the Earth's interior layers resembled a hard-boiled egg. Identify the correct labels for this simplified view.

1: crust, 2: mantle, 3: core

Which statement(s) is true about igneous rocks? Choose one: A. They were molten and have frozen into a solid form. B. They may form from lava. C. They may form around volcanoes. D. All of the possible answers are correct.

All of the possible answers are correct.

What physical characteristics can be used to distinguish individual rock types? Choose one: A. the size and shape of grains that compose the rock B. texture C. All of the possible answers are correct. D. composition

All of the possible answers are correct.

Sort the following rock examples into their appropriate rock group based on texture.

Amorphous - a rock with no crystal or grain structure Clastic - a rock derived from weathered sediments - a rock formed by lithification Crystalline - a rock with identifiable mineral crystals - a rock formed by the slow cooling of magma - a rock formed by the precipitation of water

Which of the following statements are true about partial melting?Choose one or more: A. Mafic components of the parent rock tend to go into the liquid state first during partial melting. B. As more of the rock melts during partial melting, the magma becomes more mafic than the original melt that formed. C. Felsic components of the parent rock tend to go into the liquid state first during partial melting. D. Partial melting results in magmas that are more felsic in composition than the parent rock.

As more of the rock melts during partial melting, the magma becomes more mafic than the original melt that formed. Felsic components of the parent rock tend to go into the liquid state first during partial melting. Partial melting results in magmas that are more felsic in composition than the parent rock.

Identify the true statement. Choose one: A. The series of rock stripes perpendicular to and bilaterally symmetric across the mid-ocean ridge records the sequence of the Earth's magnetic reversals over time. B. Positive magnetic anomalies occur where seafloor basalt has the same polarity as Earth's present-day magnetic field. C. All polarity chrons are the same length of time; they differ only in the magnetic strengths they represent. D. The width of each rock stripe is a measure of how long the polar direction took to change.

B. Positive magnetic anomalies occur where seafloor basalt has the same polarity as Earth's present-day magnetic field.

Identify the true statement. Choose one: A. The only two planets with moons are the Earth and Jupiter. B. Our Sun is the only star we know of that has planets associated with it. C. The composition of the giant (Jovian) planets is mainly gas and "ice." D. The Sun accounts for almost 50% of the Solar System's mass.

C. The composition of the giant (Jovian) planets is mainly gas and "ice."

Order the steps of continental volcanic arc formation.

Convergence begins 1) A subduction trench forms where the subducting plate bends downward into the mantle. 2) An accretionary prism begins to form. 3) Magma, created by flux melting of the mantle, rises through the continental lithosphere. 4) Lava erupts onto the surface, forming volcanoes.

Identify the statement that is true about the Big Bang.

It began with all matter and energy concentrated in an infinitesimally small point.

Silicate minerals Choose one: A. are the most common minerals on the Earth. B. have a silicon-oxygen tetrahedron as their structural unit. C. are classified by the manner in which the silica tetrahedra are arranged. D. All of the possible answers are correct.

D. All of the possible answers are correct.

What does grain size generally indicate about the cooling of a melt?

Larger crystals indicate the melt cooled gradually

Which statements are true about lava? Choose one or more: A.Lava is molten rock that has been erupted onto the surface of the Earth. B.Lava composition can vary greatly among different types of volcanoes. C.Lava is molten rock beneath the surface of the Earth. D.All lavas originate with the same composition that is then changed over time.

Lava is molten rock that has been erupted onto the surface of the Earth. Lava composition can vary greatly among different types of volcanoes.

Which of the following statements about lithosphere and asthenosphere is true?

Lithosphere consists of the crust and the upper mantle and behaves like a rigid layer that breaks or bends rather than flowing like the asthenosphere.

terrestrial planets

Mercury, Venus, Earth, Mars

Planets in order from the sun

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune

How are metamorphic rocks different from igneous rocks?

Metamorphic rocks are formed by solid-state changes

Identify the true statement. Choose one: A. Every mineral is affected by every type of chemical weathering reaction. B. Most of the minerals in granite weather to clay except quartz. C. Quartz weathers more quickly than other common minerals in granite. D. All minerals weather at the same rate.

Most of the minerals in granite weather to clay except quartz.

Which of the following statements is true? Choose one: A. A well-sorted clastic rock is made up of a wide range of particle sizes. B. Conglomerate consists of a single grain size. C. Pieces of broken rock produced by physical weathering are called clasts. D. All well-rounded clasts are also spherical.

Pieces of broken rock produced by physical weathering are called clasts.

Order the steps in continental rift formation.

Rifting Initiates 1) The lithospheric mantle begins to stretch horizontally and thin vertically. 2) The crust fractures, and faults develop. 3) Large fault blocks of crust slide down into the widening rift. 4) Magma erupts as lava, creating volcanoes along and near the center of the rift.

Order the steps that lead to seafloor spreading.

Rifting initiates 1) The asthenosphere beneath diverging plates rises and melts. 2) A magma chamber forms beneath the ridge axis. 3) Magma rises to the surface and erupts via submarine volcanoes. 4) Newly formed crust is moved laterally away from the ridge.

Sort likely consequences of shear stress versus uniform pressure on rocks.

Shear Stress - elongation of grains - foliation Uniform Pressure - development of large, equant grains - rounding of grains

Label each of the following minerals with the correct mineral class.

Silicate (SiO44-): quartz Sulfide (S2-): pyrite Oxide (O2-): magnetite Halide (Cl-): halite Carbonate (CO32-): calcite Native metal: copper Sulfate (SO42-): gypsum

Which of the following statements about metamorphic rocks and their characteristic environments is true?

Slate, phyllite, schist, and gneiss are found in areas of continental collision

Determine consequences of phase changes by experimenting with a mineral in the Phase Change Interactivity. Listen to the Phase Change Interactivity introduction, and then drag the yellow star to new pressure and temperature conditions on the diagram to see the effect on the mineral.

The crystal structure of the mineral changes. The species of mineral changes. The atoms in the mineral are rearranged or displaced.

Which environment is most likely to facilitate the formation of coal?

a heavily vegetated swamp with stagnant water

graphite is

a polymorph of diamond.

Humans are part of the

biosphere.

classification scheme for igneous rocks

classified into four categories, based on either their chemistry or their mineral composition: felsic, intermediate, mafic, and ultramafic.

Which of the following classes of sedimentary rock is produced by weathering and erosion of pre-existing rocks?

clastic

sedimentary rock types

clastic- loose fragments clasted together with sediment biochemical- cemented shells of organisms organic- remains of once living organisms chemical- minerals that crystalize directly from water

The tendency of a mineral to break and produce smooth, curving, shell-shaped surfaces is termed

conchoidal fracture.

alfred wegner

continental drift - theorized continents had moved - 200 million years ago, super continent pangea - proposed Incorrectly that the continents plowed through basaltic ocean basins

Metamorphic rock

has changed physical characteristics while remaining solid.

types of bonds

ionic- forms between a positive ion of sodium and a negative ion of chloride covalent- form when carbon atoms share electrons

Quartzite

is basically a solid mass of interlocking quartz grains.

Why does a delta often form where a river meets a standing body of water?

it loses velocity/energy and can no longer carry sediment

Natural cracks in rock that form due to exhumation of deeply buried rock are called

joints.

common types of metamorphism

limestones, sandstones, phyllsilicate

the earth system

lithosphere (geosphere) , biosphere, crysosphere, hydrosphere, atmosphere - nitrogen and oxygen are dominant gasses in the modern atmosphere

A metamorphic rock

may have preferred mineral orientation caused by differential stress.

The metamorphic grade of a rock is determined by observing the

metamorphic mineral assemblage.

Which of the following lists accurately reflects an increase in grain size from smallest to largest?

mud, silt, sand

protolith

original rock type

Minerals are the building blocks of?

rocks

harry hess

sea floor spreading seafloor is created at mid ocean ridges, moves away from ridges, then subducts back to mantle seafloor spreading + continental drift = plate tectonics

Place the parts of the rock cycle in the appropriate location on the image of the rock cycle below. (ROCK CYCLE)

sedimentary rock -> burial and heating -> metamorphic rock (burial and remetamorphis) -> melting (return of material to mantle by subduction) -> igneous rock -> erosion, transportation, and deposition

This figure shows air temperature values in the layers of the Earth's atmosphere. Identify each layer by dragging the labels to the correct spot on the figure.

top to bottom: - thermosphere - mesosphere - stratosphere - trophosphere

The Earth's magnetic field is created by

the flow of liquid iron in the Earth's molten outer core.

The great varieties of minerals on the Earth are classified by mineralogists into a small number of groups on the basis of

the negative ion or ionic group in their chemical composition.

rock

- coherent, holds together - naturally occurring - made by minerals or a body of glass

Order the steps involved in fractional crystallization.

1) Magma, after entering through the bottom of the magma chamber, reaches the top of the chamber where temperatures are lower. 2) Magnesium- and iron-rich minerals begin to crystallize. 3) Mineral crystals, having a higher density than liquid magma, sink to the bottom of the magma chamber. 4) The magma shifts toward a more intermediate composition.

Order the compositions of magmas produced via melting from lowest temperature to highest. What composition of magma is produced by melting at lower temperatures? At higher temperatures?

1) felsic 2) intermediate 3) mafic 4) ultramafic

Rank the following steps describing how a clastic sedimentary rock forms from its pre-existing parent rock.

1) weathering 2) erosion 3) transportation 4) deposition 5) lithification

types of chemical weathering

1. Dissolution - affects salts and CO3 mins 2. Oxidation - rusting 3. Hydrolysis - transforms mins to clay 4. Hydration - absorption of water

Magmas can have a variety of chemical compositions for which of the following reasons? Choose one: A. All of the possible answers are correct. B. Two magmas may mix together to form a third of differing composition. C. Source rocks undergo varying degrees of partial melting, producing magmas of a different composition than the rock. D. Melts may come from different source rocks.

All of the possible answers are correct.

Which statement accurately describes the relationship between air pressure and altitude, as illustrated in this figure?

At the top of Mt. Everest, air pressure is 30% of what it is at sea level (altitude of zero).

Order the steps of volcanic island arc formation.

Convergence begins 1) A subduction trench forms where the subducting plate bends downward into the mantle. 2) An accretionary prism begins to form. 3) Magma, created by flux melting of the mantle, rises through the overriding plate. 4) Lava erupts onto the surface, forming volcanoes.

Which of the following statements is true?Which of the following statements is true?

Growing and harvesting crops leads to nutrient depletion of the soil.

Gas giant planets

Jupiter, Saturn, Uranus, Neptune

Compare and contrast the melting of water and rock by matching each statement to the appropriate category below.

Melting of Water - The composition stays the same. Melting of Rock - Partial melting can take place. Applies to Both - A change of state takes place. Applies to Neither - This phase change takes place at 100°C.

Which of the following statements regarding the Big Bang theory are true?

The Universe is considerably older than Earth. All matter in the Universe was once confined to a single point.

Which of the following is a characteristic of all rocks?

They are a collection of minerals or a body of glass

Which statement is true according to the rock cycle?

Uplift, weathering, burial, and heating/melting can transform one rock type into another.

A mineral, as geologists understand the term, is a naturally occurring solid substance with a definable chemical composition and

a fixed crystalline structure.

The island of Hawaii is the youngest, and the islands get progressively older to the northwest. Plate tectonic theory explains this as

a hot spot currently sitting under Hawaii and the Pacific Plate moving across it in a northwesterly direction.

Place the label that identifies the correct layer of the Earth on the following diagram.

bottom to top: - inner core - outer mantle - lower mantle - upper mantle - crust

Label the polarity chrons with the appropriate title and polarity. Note that some of the chrons contain short-duration subchrons. The boundaries between the chrons are indicated by the heavy black lines. The thickness of layers on this diagram represents the duration of time during which the layer accumulated.

bottom to top: - oldest reversed polarity interval - oldest normal polarity layer - reversed polarity chron that lasted the longest - youngest normal polarity layer

mineral groups

carbonates (co32): calcite; construction, concrete oxides (o2): magentite, bauxite; fe and al sulfates (so42): gypsum sulfides (s2, s): galena, pyr, chalcopyrite, spahlerite halides (cl, f): halite, flouride; chemical flux in steel native elements (au, ag, cu, s, c): graphite, sulfur, diamond, silver; jewlery, led

Identify likely consequences of recrystallization as a result of metamorphic activity.

changes in the size of mineral grains changes in the shape of mineral grains

Recrystallization

changes the texture (shape and size) of the grains.

Identify outcomes of chemical weathering. Choose one or more: A. more rounded fragments B. smaller fragments C. chemically altered minerals D. clay minerals

chemically altered minerals clay minerals

Which type of chemical bond occurs when atoms share electrons, as shown in this diagram?

covalent

According to the theory of plate tectonics, the plates are: Choose one or more:

discrete pieces of lithosphere which move with respect to one another. moved by the creation of new crust and subduction of old crust.

Earth's magnetic field

due to the flow of material in the liquid outer core

The earliest nebulae to form in the Universe were made almost entirely of

hydrogen and helium.

A crystalline rock

is composed of interlocking minerals that grew together.

Granite

is felsic in composition.

Felsic (or silicic) magma

is more viscous than mafic magma.

Classify the silicate groups based on how many oxygen atoms are shared by each silicon-oxygen tetrahedron with a neighboring silicon-oxygen tetrahedron. To see a larger version of the image, scroll down.

isolated tetrahedra: 0 single chain: 2 double chain: 2 or 3 two-dimensional sheet: 3 three dimensional framework: 4

The lithosphere and asthenosphere are known as physically different layers of the Earth because they behave very differently when deformed. Sort the items below into the correct boxes based on characteristics of the lithosphere and asthenosphere.

lithosphere: - mantle and crust - brittle - colder asthenosphere: - mantle only - ductile - warmer

Which of the following traps cosmic rays and shields life on the Earth from excessive radiation?

magnetosphere

Which of the Earth's layers accounts for most of the volume of the Earth?

mantle

The center of a mid-ocean ridge is where

new oceanic lithosphere is created.

The two most common gases of the Earth's atmosphere, and their percentages, are

nitrogen (N2) at 78%, and oxygen (O2) at 21%.

Coal is a form of

organic sedimentary rock.

Identify outcomes of metamorphic change.

phase change of minerals growth of new minerals changes in mineral size and shape creation of foliation

According to current plate tectonics theory,

plates are composed of the crust and the uppermost part of the mantle.

Big Bang Theory

proposes that all matter and energy in the universe started out as a single infinitesimally small point - exploded and has been expanding ever since

An unknown mineral scratches glass, has only average specific gravity, and shows no cleavage but does show conchoidal fracture. Which of the following could it be?

quartz

Which of the following variables could influence the width of marine magnetic anomalies on the floor of the ocean?

rate at which the plates are moving away from the mid-ocean ridge duration of the magnetic polarity event

Which of the following fits the definition of a mineral?

salt, because it's crystalline

mid ocean ridge

shallower and deeper than abyssal plains - where oceanic crust forms

Bowen's reaction series

shows that minerals in a cooling magma crystallize in a predictable order.

The silica-oxygen tetrahedra is the building block of which chemical class of minerals?

silicates

Which of the following classes of minerals are most abundant in the Earth's crust and mantle?

silicates

Which of the following pairs of elements composes most of the Earth's crust?

silicon and oxygen

dentify the list of rock types that is ordered by increasing degrees of metamorphism (i.e., from lower to higher grade).

slate, phyllite, schist, gneiss

During World War II, the military imaged the seafloor by sending pulses of sound waves down through the water and measuring the time it took for the sound to bounce off the seafloor and return to the receiver. This method is called

sonar.

Categorize processes related to transform boundaries. Sort the following processes those likely to be related to a transform boundary or those likely associated with other boundary types.

transform boundary: - earthquakes other boundary: - divergence - convergence - subduction