Physical Science Summer Midterm Chapters 20-23

Unconformities

Gaps in the rock record are called

Stromatolites, when? why do we care?

Precambrian

Perched-

When a perched water table intersects the surface on a hillside, the result is a spring. Because rock layers are not always continuous, sometimes a low permeability layer can stop and hold the downward-percolating water above the water table. When this happens, perched water table is created. Wherever the water table meets the land surface, groundwater emerges from an aquifer as a spring, stream, or lake. Springs can generally be found where the water table (or a perched water table) intersects the surface along a slope, such as on a hillside or coastal cliff. Because water tends to leak out of the ground through cracks and breaks in a rock, springs are often associated with faults. In fact, field geologists can often locate faults by looking for springs. When the water table intersects the land surface, groundwater is released. From the perched water table, water is released via a spring; from the main water table, water is released by or into a stream.

Glaciers - how are they formed

Winter snowfalls do not melt completely so snow accumulates. Deepest layers of snow are compressed causes deepest snow to melt, water trickles down and freezes

Radiometric dating

gives the actual age of a rock by measuring the ratio of radioactive isotopes to their daughter products.

Cambrian explosion?

great diversity of life forms evolved during this time 543 to 490 Ma

What is meant by the phrase 100-year flood?

"One hundred year flood" is a statistical term, indicating a 1-in-100 chance that a flood this size will occur during any year. Perhaps a better term would be "1-in-100 chance flood."

turbulent vs laminar flow

Laminar flow—slow and gentle Turbulent flow—fast and rapid

Deserts - mechanical weathering

- Stream water carries dissolved substances that chemically weather and erode rock.

Glaciers

- a large mass of ice formed by the compaction and recrystallization of snow, moving downslope under its own weight.

Oceans

97.2% of Earth's water is in oceans. Most of earth's surface area is ocean, so the evaporation and precipitation are greatest over oceans.

The most common source of groundwater is _______ ?

98.5% resides in porous regions beneath Earth's surface.

Whats the difference between rocks and minerals

A Rock is a natural material that is made of multiple minerals. Igneous, Sedimentary, Medimorphic. Minerals A chemical that naturally occurs and has a crystal structure. Gold, Diamond, Sulfer.

cirque

A bowl shaped basin carved by a glacier.

Continental Drift Theory

A hypothesis that stated that the world's continents were once joined together as a super continent that Alfred Wegener called Pangaea. Wegener supported his hypothesis with impressive geologic, biologic, and climatologic evidence.

aretes-

A jagged, narrow ridge that separates two adjacent glacier valleys or cirques.

horns-

A pointed, mountain peak, typically pyramidal in shape, bounded by the walls of three or more cirques.

Asthenosphere

A subdivision of the upper mantle situated below the lithosphere, a zone of plastic, easily deformed rock

Age of the Reptiles, when?

Mesozoic Era

Artesian

A type of confined aquifer that flows upward to Earth's surface without need for pumping. Pressure from water in long sides of aquifer pushes water up well shaft

Alpine vs Continental

APLINE-a glacier in mountainous regions that flows down preexisting valleys. CONTINENTAL-- A glacier that covers much of a continent or large island.

accumulation vs ablation

Accumulation-the amount of snow added and the process of adding snow to a glacier Ablation-The annual amount of snow lost and the process of losing ice by a glacier

advance vs. retreat

Advance-Glacier moves forward (more ice is supplied than melts) Retreat- More melt occurs (moves backward)

VOCABS

Anticline: An up-fold in rock with relatively old rocks at the fold core; rock age decreases with horizontal distance from the fold core. Asthenosphere: A subdivision of the upper mantle situated below the lithosphere, a zone of plastic, easily deformed rock. Body wave: a type of seismic wave that travels through Earth's interior Continental Drift: A hypothesis by Alfred Wegener that the world's continents are mobile and have moved to their present positions at the ancient supercontinent Pangaea broke apart. Convergent plate boundary: A plate boundary where tectonic plates move toward one another; an area of compressive stress where lithosphere is recycled into the mantle or shortened by folding and faulting Core: The central layer of Earth's interior, divided into an outer liquid core and an inner solid core Crust: Earth's outermost layer Divergent plate boundary: A plate boundary where lithosphere plates move away from one another-a spreading center; an area of tensional stress where new lithosphere crust is formed. Earthquake: The shaking of trembling of the ground that happens when rock under Earth's surface moves or breaks Fault: A fracture along which movement of rock on one side relative to rock on the other side has occurred Isostasy: The process by which oceanic crust and continental crust come into vertical equilibrium with respect to the mantle; the dense oceanic crust sits lower in the mantle than the less-dense continental crust Lithosphere: The entire crust plus the rigid portion of the mantle that is above the asthenosphere Mantle: The middle layer in Earth's interior, between the crust and the core Mohorovičić discontinuity: (Moho) The crust-mantle boundary; this marks one of the depths where the speed of P-waves traveling through Earth suddenly increases Paleomagnetism: The natural, ancient magnetization in a rock that can be used to determine the polarity of Earth's magnetic field and the rock's location of formation Plate tectonics: The theory that Earth's lithosphere is broken into pieces (plates) that move over the asthenosphere; boundaries between plates are where most earthquakes and volcanoes occur and where the lithosphere is created and recycled Primary Wave: (P-Wave) A longitudinal body wave that compresses and expands the material through which it moves; it travels through solids, liquids, and gases and is the fastest seismic wave Rift: (Rift Valley) A long, narrow gap that forms as a result of two plates diverging Seafloor spreading: The moving apart of two oceanic plates at a rift in the seafloor Secondary wave: (S-wave) A transverse body wave that vibrates the material through which it moves side to side or up and down; it cannot travel through liquids and so does not travel through Earth's outer core Subduction: The process in which one tectonic plate bends and descends beneath another plate at a convergent boundary Surface Wave: A type of seismic that travels along Earth's surface Syncline: A down-fold in rock with relatively young rocks at the fold core; rock age increases with horizontal distance from the fold core Transform plate boundary: A plate boundary where two plates are sliding horizontally past each other, without appreciable vertical movement

What is an aquifer? A spring?

Any water-bearing underground region through which groundwater can flow is called an aquifer. These reservoirs of groundwater underlie the land surface in many places and contain an enormous amount of water. More than half the land area in the US is underlain by aquifers. Whenever the water table meets the land surface, groundwater emerges from an aquifer as a spring. Springs can generally be found where the water table (or perched water table) intersects the surface along a slope, such as on a hillside or coastal cliff. Because water tends to leak out of the ground through cracks and breaks in a rock, springs are often associated with faults. In fact, field geologists can often locate faults by looking for springs.

Plutons - batholiths and dikes

Batholiths-are very large intrusions, many km's long and wide and very thick. Usually granitic due to slow underground cooling. Either a big pluton or a large body made up of smaller plutons Dikes- Formed when magma squeezes across rock layers and cools (vertically).

Body waves vs Surface waves

Body waves travel through Earth's interior. Body waves are further classified as either primary waves (P-waves) and secondary-waves (S-waves) Surface waves travel along Earth's surface.

cut bank vs point bar

CUT BANK-a steep bank on the outside bend of a river's channel; an area of erosion. POINT BAR- a sandy, gentle bank on the inside bend of a rivers channel; an area of deposition.

Trilobites, when?

Cambrian 521

Shelled organisms, when?

Cambrian 543-490

Shelled egg, when

Carboniferous 290 mya

Age of Mammals, when?

Cenozoic Era

Lithification - Compaction vs. cementation

Compaction—Weight of overlying material presses down upon deeper layers. Cementation—Compaction releases "pore water" rich in dissolved minerals. This mineralized "pore water" acts as a glue to cement sediment particles together.

Metamorphisis - Contact vs Regional

Contact metamorphism: a body of rock is intruded by magma is typically associated with high temperatures and high water content—lots of chemical activity, not much, or no, mechanical deformation. Regional metamorphism: the alteration of rock by both heat and pressure over an entire region rather than just near a contact between rock bodies.

Five properties of minerals-

Crystal form Hardness Cleavage and fracture Color Density

Dino Dyout, when?

Dec. 14 to 26 end of the Cretaceous Period

Coal deposits, when?

Dense swamplands 354 to 290 Ma

Age of the Fishes, when?

Devonian 417 to 354 Ma

Pangea, Gondwanaland, Laurasia, Rodnina - How are these four related?

During the Ordovician the ancestral continental landmasses of South America, Africa, Australia, Antarctica, and India were merging together to form a new supercontinent called Gondwanaland. Throughout the Ordovician, Gondwanaland shifted southward, finally settling on top of the South Pole. With so much landmass over the South Pole, the latter part of the Ordovician was one of the coldest times in Earth history. Ice and massive glaciers covered much of Gondwanaland, draining the shallow seas. As sea level dropped, many shallow water invertebrates were deprived of their habitat. During the Silurian period, Gondwanaland remained close to the South Pole, and the ancestral continents of North America, Europe, and Siberia were located near the equator. The climate began to stabilize and warm, which resulted in the melting of many large glaciers and a general rise in the sea level. Shallow seas moved in to cover continental interiors. These reefs blocked the circulation of water between the inland seas and the open oceans. As water in the inland seas evaporated, deposits of gypsum and other evaporite minerals were left behind. During the Devonian period, the ancestral continents of North America, Europe, Siberia, and North China merged to form another super continent known as Laurasia, which positioned near the equator. The super continent of Gondwanaland remained in the Southern Hemisphere. Throughout the Carboniferous and into the Permian, Laurasia and Gondwanaland became close and began merging into the supercontinent Pangaea. The collision of Gondwanaland with Laurasia created the Appalachian Mountains and Ural Mountains. At the end of the Permian period, sea level lowered. The lowering was a result of glaciation as Pangaea drifted near the South Pole, the collision of Gondwanaland and Laurasia to form Pangaea, and tectonics and climate change. All continental landmasses merged to form a single super continent - Rodinia (Russian for homeland). Rodinia stretched between the North and South Poles and then split to form other continental configurations.

What is the basic compositions of the different layers of the earth?

Earth's core is mainly composed of iron and smaller amounts of nickel. Mantle - Hot iron rich silicate rock Crust: subdivided into continental crust and oceanic crust. The crust of the ocean basins is compact, thick and composed of dense basaltic rocks. Continental crust is thicker and composed of granitic rocks. Because granitic rocks are less dense than basaltic rocks, most of the continental crust is above sea level.

Crust

Earth's outermost layer

Metamorphic Rock - Foliated vs Non-foliated

FOLIATED- Layered in sheets Slate Schist Gneiss NON- Not layered Marble Quartzite

Alluvium

Features deposited by flowing water A fan-shaped deposit of sediment on land.

Fault - footwall vs hanging wall block

Footwall block: the half containing the fault surface where someone could stand Hanging Wall block: the fault surface of the other half is inclined and would make standing impossible.

Pangaea

Formed by a continental-continental collision that ultimately resulted in the formation of the supercontinent Pangaea.

Groundwater vs soil moisture

Groundwater- occurs in the saturated zone—water has filled all pore spaces. Soil moisture- is above the saturated zone in the unsaturated zone—pores filled with water and air.

what are the three types of rocks, how they are formed-

Igneous Formed from cooling and crystallization of magma or lava Sedimentary Formed from preexisting rocks subjected to weathering and erosion Metamorphic Formed from preexisting rock transformed by heat, pressure, or chemical fluids

what layers of the earth are solid, liquid or in-between?

Inner core solid - Inner Core: the iron and nickel are solid. (Although the inner core is very hot, intense pressure from the weight of the rest of the Earth prevents the inner core from melting). Outer core molten - Outer Core: the iron and nickel are liquid (because less weight is exerted on the outer core) Lower mantle solid Upper mantle plastic

Seismic Waves

Internal movements that generate waves that travel through Earth's interior and across Earth's surface. Measuring the speeds of seismic waves provides clues about Earth's composition.

Weathering - mechanical vs. chemical

Mechanical weathering—breaking and disintegration of rocks into smaller pieces. Chemical weathering—chemical decomposition and transformation of rock into one or more new compounds.

What's a Moho?

Mohorovičić discontinuity: (Moho) The crust-mantle boundary; this marks one of the depths where the speed of P-waves traveling through Earth suddenly increases

Moraines vs drumlins

Moraines- Lateral moraine: forms along the sides of glaciers; dark fringe of rocks and other debris. When the glacier melts, it forms low ridges. Medial moraine: is a sediment-rich belt in the center of the glacier. It forms where two glaciers join, trapping their lateral moraines within the combined glacier; not well preserved. Terminal moraine: forms at the termination of a glacier and generally marks the glacier's farthest downhill extent. Large and conspicuous DRUMLINS-An elongated hill of glacial till in the shape of an inverted spoon or half-buried egg.

Describe 3 types of convergent margins

Oceanic-oceanic convergence-occurs when two oceanic plates meet and the older (and therefore cooler and denser) plate slides beneath the younger, less-dense plate. The process in which one plates bends and descends beneath the other is called subduction, and the area where is occurs is called the subduction zone. At earth's surface, subduction zones are marked by deep ocean trenches that run parallel to the edges of convergent boundaries. • When two oceanic plates converge, older and denser plate descends beneath the other (subduction). • As plate descends, partial melting of mantle rock generates magma and volcanoes. • If volcanoes emerge as islands, a volcanic island arc is formed (Japan, Aleutian islands, Tonga islands). Oceanic-continental convergence-occurs when an oceanic plate collides with a continental plate. In this case, the denser oceanic plate subducts beneath the less-dense continental plate. A deep ocean trench forms offshore where converging plates meet. As with oceanic-oceanic convergence, magma is generated. • Denser oceanic plate subducts beneath the less-dense continental plate. • As plate descends, partial melting of subducting rock generates magma. • Mountains produced by volcanic activity from subduction of oceanic lithosphere and compression from convergence are called continental volcanic arcs (Andes and Cascades). Continental-continental convergence-occurs when two continental plates collide. In this case, both plates are composed of buoyant granitic-type rocks, Because the colliding plates have similar densities, neither sinks below the other-so in continental-continental convergence there is no subduction. Instead, the convergence is more like a head on collision. Compression causes the plates to break and fold up on each other making the crust very thick. Intensely compressed and metamorphosed rock defines the zone where continental plates meet. In contrast with convergence involving two oceanic plates or one continental and one oceanic plate, volcanic activity is not a characteristic feature of continental-continental collisions-but earthquakes are. The collision between continental plates has produced some of the most famous mountain ranges, one of them being the snow-capped Himalayas, the highest mountain range in the world. • Continued subduction can bring two continents together. • Less dense, buoyant continental lithosphere does not subduct. • The result is a collision between two continental blocks. • The process produces mountains (Himalayas, Alps, Appalachians). • The continent to continent collision of India with Asia produced—and is still producing—the Himalayas • Sites of the deepest, strongest earthquakes

The six principles of relative dating

Original horizontality: New layers of sediment are horizontally laid down over older layers. Superposition: In undeformed sequences of rock, top layers are younger than bottom layers. Cross-cutting: A fault or intrusion that cuts into a rock is younger than the rock it cuts through. Inclusion: Any inclusion is older than the rock containing it. Lateral continuity: Allows us to date separated rock outcrops from similar characteristics. Faunal succession: Fossil organisms follow one another in a definite, irreversible time sequence.

P waves vs S waves

P-waves and S-waves are types of body waves. P-waves (primary waves), like sound waves, are longitudinal. They compress and expand the rock as they move through it. Primary waves are the fastest of all seismic waves and are the first to register on a seismograph. Because both solids and fluids can compress and expand, P-waves can travel through any type of material-solid rock, magma, water, or air. Secondary waves, like waves produced on a vibrating violin string, are transverse-they vibrate the particles of their medium up and down and from side to side, perpendicular to the direction of wave travel. Because S-waves travel more slowly than P-waves, they are the second waves to register on a seismograph. S-waves cannot move through fluids-they only travel through solids.

Vertebrates, when?

Paleozoic Era The Ordovician Period 490 to 443 Ma

Theory of Plate Tectonics

Plate tectonics is the unifying theory that explains the dramatic, changing surface features of the Earth. Earth's lithosphere is divided into 8 large plates and some smaller ones. The continents move because they are embedded within drifting plates. Plates are sections of Earth's strong, rigid outer layer-the lithosphere. Plates consist of uppermost mantle and overlying crust. Plates overlie and ride atop the weaker asthenosphere. There are eight major lithospheric plates. Plates are in motion and continually changing in shape and size. Largest plate is the Pacific Plate. Several plates include an entire continent plus a large area of seafloor. Earth's plates move in different directions and at different speeds. Continental plates tend to move slowly. Oceanic plates tend to move faster. Interactions between plates occur along plate boundaries. Creation and destruction of lithosphere occurs along plate boundaries. Earthquakes, volcanoes, and mountains occur along plate boundaries-and sometimes along former plate boundaries. Three plate boundaries: Divergent Plate Boundaries-where plates move away from each other. Magma generation and lithosphere formation Convergent Plate Boundaries-where plates move toward each other. Magma generation and lithosphere destruction. Oceanic crust is destroyed. Continental crust is deformed. Deep earthquakes Transform Fault Boundaries-where plates slide past each other. No magma generation, no formation or destruction of lithosphere

Earthquakes - two systems use for measuring them and what they are based on

Richter scale: measured the energy released by an earthquake in terms of ground shaking. Richter magnitude is based on the maximum seismic-wave amplitude of an earthquake, as recorded by a seismograph. The Richter scale is still commonly used, but earthquakes are now measured by moment magnitude. Today, when you hear about an earthquake, it is simply described as a "magnitude-7 earthquake," with no mention of the Richter Scale

Anatomy of a sand dune, how are they formed?

Sand dunes begin to form where airflow is blocked by an obstacle, such as a rock or a clump of vegetation. As wind, sweeps over and around the obstacle, the wind speed slows, causing sand grains to fall out of the air in the wind shadow. The falling sand forms a mound and blocks the flow of air even more. With more sand and more wind, the mound grows into a dune, which, with continued growth, begins to "move" downwind. The dune moves because grains on the windward slope are blown up and over the crest of the dune, falling on the leeward slope. In this way, wind removes sand from the back of the dune and redeposits it on the front of the dune. Over time, this continuous process moves the entire dune.

Volcanoes - three types and their outlines or shapes

Shield- Cinder cone- Composite-

spits-

Submerged ridges of sand that rise above the open waters and form continuations of the beach as finger like pieces of land

Surface water and landscape changes

Surface water includes streams, rivers, lakes, and reservoirs

Folds - Syncline vs Anticline

Syncline: the layers tilt in toward the fold axis, the fold is called a syncline. The rocks at the center, or core, of a syncline are the youngest, and as you move horizontally from the axis, the rocks get older and older. Anticline: if the fold layers fold layers tilt away from the axis, the fold is called an anticline. The rocks in the core of an anticline are oldest, and as you move horizontally away from the axis, the rocks get younger. Another way to think about this concept is that anticlines are pushed upward into an arch, and synclines are pushed downward into a sag.

Detritus

TO LESSEN OR WEAR AWAY

The relationship between crystallization and % silica

The crystallization points of silicate minerals strongly depend on the amount of silica they contain. As magma cools, the first minerals to crystallize have the highest (hottest) melting points and the lowest amount of silica. The last minerals to crystallize have the lowest (coldest) melting points but the highest silica content. Conversely, high-silica minerals melt at lower temperatures than do low-silica minerals.

Lithosphere

The entire crust plus the rigid portion of the mantle that is above the asthenosphere

Transform Fault

The fracture zone that forms a transform plate boundary. Most transform faults are found in the ocean basin and connect offsets in the mid-ocean ridges.

Estuary-

The geographic land area on which runoff water from precipitation gathers and flows into a single body of water

Half-life, and how the age of an object can be determined using it

The half-life of a radioactive isotope is the amount of time it takes for half of the material to decay to its daughter product. When the parent material decays to half its original amount, the time is one half-life. When one quarter of the parent material remains, the time is two half-lives. When one-eighth remains, the time is three half-lives and so on. To date geologically young objects, and especially for dating organic matter, carbon-14 is the isotope of choice. Carbon-14 has a relatively short half-life (5760 years), so it is useful for dating geologically recent events, within the last 50,000 years or so. To date older materials, radioactive elements such as uranium are used. Many common rocks contain trace amounts of uranium, and only a small amount is needed to perform the laboratory analysis. Uranium-238 decays to its stable daughter isotope lead-207. No other natural sources exist for these two isotopes of lead; therefore, any lead-206 and lead-207 found in a rock today were at one time uranium. If for example, a sample contains equal numbers of uranium-235 and lead-207 atoms, the age of the sample is one uranium-235 half-life-704 million years. If on the other hand, a sample of uranium contains only a small amount of lead-207, the sample is ounger than one half-life (a single half-life has not passed yet)

Meteorite, Impact crater, Iridium, Dinosaurs - How are these four related?

The most popular explanation of the great extinction was the extinction was caused by the impact of a very large meteorite. The meteorite hit Earth with such force that it wreaked havoc in many ways. The impact caused large, widespread earthquakes and huge shock waves. It also released enormous amounts of heat, which resulted in extreme firestorms. In the meteorite impact's aftermath, a gigantic light-blocking cloud of enveloped Earth. The dust cloud spread throughout the atmosphere and lasted long enough to stop the process of photosynthesis. So the cloud not only chilled Earth but also devastated the food supply. Evidence for this theory is found in the rock record. As the dust settled, a layer of iridium-enriched sediment was deposited. The element iridium is rare at Earth's surface, but it is abundant in meteorites. So the iridium layer that marks the boundary between Cretaceous and Tertiary periods (called the K-T boundary) is hypothesized to have been spread worldwide by the extraterrestrial impact. The Chicxulub crater (Dated at 65 million years), located off the Yucatan coast in Mexico, is hypothesized site of impact. Both the K-T boundary layer and the Chicxulub crater coincide with the time of the great Cretaceous extinction. An alternative to the Alvarez hypothesis suggests that the iridium layer may have been generated from massive volcanic eruptions. The ash and debris from these eruptions also could have blocked the sun. A third possibility is that large-scale volcanic eruptions could have been caused by the impact of an extraterrestrial object. Whatever the cause, the Creaceous extinction dramatically marked the close of the Mesozoic era.

Isostasy

The word isostasy derives from Greek roots "iso" meaning equal and "stasis" meaning standing-equal standing. Isostasy is the vertical positioning of the crust so that gravitational and buoyant forces balance one another. Low density crust floats on the denser, underlying mantle. Continents are high and oceans low because of Isostasy. Variations in surface elevations result from variations in the thickness and the density of the crust. Areas of continental crust stand higher that areas of oceanic crust, because continental crust is thicker and less dense than oceanic crust.

Five groups of minerals

They are naturally occurring (formed naturally rather than manufactured). They are crystalline solids. They have an orderly and repeating arrangement of atoms, ions, and/or molecules. They have a specific chemical composition, with slight variations. They are generally inorganic.

stream speed-

Three variables influence the speed of water in a stream: stream gradient, stream discharge, and channel geometry. Gradient is the vertical drop in the elevation of the steam channel divided by horizontal distance for that drop. If we look at a long profile of a stream, we see that the gradient is steep near the stream's headwaters and gentler, almost horizontal, near its mouth. Because of gravity, stream speed tends to be greater where the stream gradient is steep. Downstream, discharge and channel geometry also influence stream speed. Discharge is the volume of water that passes a given location in a channel in a certain amount of time. It is directly proportional to the cross-sectional area of the channel-the width times the depth-and to the average stream speed: Discharge = cross sectional area x average stream speed OR to put it another way, Average stream speed = discharge / cross-sectional area. Channel Geometry is the shape of the channel and it greatly influences stream speed. Consider two streams that have the same cross-sectional area but different channel shapes. Water flowing in a stream touches the channel bottom and sides. Friction between the water and the channel slows the stream speed. So, the shape of a channel determines the amount of water in contact with the channel. The greater the contact area, the greater the friction. If the stream channel is rounded and deep, as opposed to flat-bottomed and relatively shallow, the stream speed will be faster because there is less water in contact with the channel. Stream speed also varies within the channel. Flow speed is slower along the streambed (due to friction), and flow speed is faster near the water's surface. In a large stream flowing in a straight channel, the maximum flow speed is found midchannel. In a stream running through a bending, looping channel, the maximum flow speed is found toward the outside of each bend.

Unconfined vs Confined aquifers.

Unconfined -Is covered by permeable rock and can receive water from the surface. Water table rises or falls depending on amount of water entering and leaving the aquifer, only partly filled with water Confined- Lies between two layers of less permeable rocks and is filled with water. Water trickles down through cracks in the upper layers of less permeable rock, a nearby water source, such as an underground river or lake, or a nearby unconfined aquifer

Sedimentary rock - clastic vs chemical

clastic rocks—transported sediment particles—bits and pieces of weathered rock (shale, sandstone, conglomerate) Chemical rocks—sediments that were once in solution (travertine, halite, limestone)

Uniformitarianism

is the assumption that Earth's geology is the result of slow processes over long periods of time.

Delta - description and distributaries

is where a flowing stream meets a standing body of water. The flow slows down and the stream dumps sediment.

Karst Regions

lots of sinkholes, sharp rugged surfaces, thin soils, and more-

How are caves/caverns formed

reaction of carbonic acid released into the groundwater

Relative Dating

relative age, the ordering of rocks in sequence by comparative ages

What is necessary to make a 'true' glacier?-

snow accumulates to form ice and the ice mass begins to flow under its own weight.

stalactites vs stalagmites

stalactites- from water rich in calcium dripping from a cave ceiling and from a cave ceiling downward stalagmites-grow from the floor of a cave

3 things that affect stream speed

stream gradient, stream discharge and channel geometry

Lagoon-

stretch of salt water separated from the sea by low sandbank or coral reef

Seamounts-

submerged volcanic structures

Drainage Basins-

the area from which a single stream or river and tributaries drains all of the water

Erosion

the physical removal of material by mobile agents such as water, wind, ice, or gravity.Erosion does not occur in place. It involves movement

drift (Glacial deposits)-

the rock material carried and deposited by glaciers

Three aspects of change

water, wind, ice Water is the dominant agent of change altering our natural landscape