Study Guide: Midterm Exam
Concentrate your studies in the following areas. Questions for the Midterm Exam will come principally from this material.
Lutgens and Tarbuck Textbook:
Minerals (Chapter 1) * Know the definition of a mineral. a solid inorganic substance of natural occurrence * Know the basic definition of a rock. the solid mineral material forming part of the surface of the earth and other similar planets, exposed on the surface or underlying the soil or oceans * Know how atoms of the same element are related. Atoms of the same element must have the same number of protons which is the atomic number. What do they have in common? They all have protons * Know definitions for the following terms: valence electrons, an electron of an atom, located in the outermost shell (valence shell) of the atom, that can be transferred to or shared with another atom. An electron in one of the outer shells of an atom that can participate in forming chemical bonds with other atoms nucleus, the central and most important part of an object, movement, or group, forming the basis for its activity and growth. atom, the basic unit of a chemical element element, ion, and chemical compound. * Know the difference between ionic and covalent bonds. Ionic compounds contain a metal cation bonded to a nonmetal anion. This means that the first element in the compound's name and formula is to the left of the zig-zag line on the periodic table above. Covalent compounds contain NO metals. They contain no ions at all. Instead, covalent compounds contain nonmetals only. They are composed completely of elements to the right of the zig-zag line on the periodic table above. Which is typically stronger? Ionic * Know the components and structure of the silicon-oxygen tetrahedron that makes up silicate minerals. This structure is in fact a compound anion; that is, while as a unit it carries a negative charge it is composed of atoms with individual negative and positive charges. At the center of the structure is the silicon ion with a positive four charge. Surrounding the silicon in a highly symmetrical structure are four oxygen ions, each of which carries a negative two charge. * Know and understand the following physical properties of minerals: luster, gentle sheen or soft glow, esp. that of a partly reflective surface. color, The intrinsic color of the mineral. streak, The color of the powdery residue of a mineral left behind when you drag it across an unglazed porcelain plate hardness, Measure of the resistance of a mineral to scratching (not breakage) cleavage, Breakage of a mineral along a flat plane of weakness. fracture, Uneven breakage (non-planar breakage) and specific gravity. the ratio of the density of a substance to the density of a standard, usually water for a liquid or solid, and air for a gas. * What mineral found in nature is the hardest known to man? Diamond Name some of the softer minerals known. quartz * What minerals are known for their perfect cleavage in one direction micas have a perfect cleavage in one direction that is easy to produce? What minerals are known for perfect cleavage in three directions? calcite has a perfect cleavage in three directions that is also easy to produce * Be able to define atomic number, the number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table. atomic mass, the mass of an atom of a chemical element expressed in atomic mass units. It is approximately equivalent to the number of protons and neutrons in the atom (the mass number) or to the average number allowing for the relative abundances of different isotopes. protons, a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron, but of opposite sign neutrons, a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen. and electrons a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.. Also, know the following formula and be able to apply it: Atomic Mass = # of protons + # of neutrons. * Know the eight most common elements in the earth’s crust. Oxygen 46.6%
Silicon 27.7 Aluminum 8.1 Iron 5.0 Calcium 3.6 Sodium 2.8 Potassium 2.6
Magnesium 2.1 Also, know the different mineral groups (i.e., silicates, a salt in which the anion contains both silicon and oxygen, esp. one of the anion SiO42-. carbonates, a salt of the anion CO32-, typically formed by reaction of carbon dioxide with bases sulfides, a binary compound of sulfur with another element or group. etc.). See Table 1.1 on page 39 for the non-silicate mineral groups. Which of the mineral groups is most common in the earth’s crust?

Rocks (Chapter 2)

* Be able to name and describe the three main rock types found in the earth’s crust (i.e., igneous, is one of the three main rock types, the others being sedimentary and metamorphicrock. Igneous rock is formed through the cooling and solidification of magma or lava. sedimentary, Sedimentary rocks are types of rock that are formed by the deposition of material at the Earth's surface and within bodies of water. Sedimentation is the collective name for processes that cause mineral and/or organic particles (detritus) to settle and accumulate or minerals to precipitate from a solution. and metamorphic). metamorphic rock definition. Rock that was once one form of rock but has changed to another under the influence of heat, pressure, or some other agent without passing through a liquid phase. Note: Examples are marble, which can be formed from limestone, and slate, which is formed from shale. * Have a basic understanding of the rock cycle. an idealized cycle of processes undergone by rocks in the earth's crust, involving igneous intrusion, uplift, erosion, transportation, deposition as sedimentary rock, metamorphism, remelting, and further igneous intrusion * Know how crystal size in igneous rocks is related to cooling history. * Know the basic differences between intrusive Intrusive igneous rocks are formed from magma that cools and solidifies within the crust of a planet, surrounded by pre-existing rock (called country rock), the magma cools slowly, and as a result these rocksare coarse grained. and extrusive igneous rocks. Igneous rocks which form by the crystallization of magma at the surface of the Earth are called extrusive rocks. They are characterized by fine-grained textures because their rapid cooling at or near the surface did not provide enough time for large crystals to grow. * Be able to describe the following igneous rock textures: fine-grained, have small grains, less than a millimeter across, that are invisible to the naked eye. Hand samples of fine-grained rocks often appear homogeneous—they look the same throughout the rock. Hand lenses, magnifying glasses, or microscopes can reveal the small crystals in these rocks. vesicular, Vesicles are fossil bubbles. So, a rock that looks like Swiss cheese has a vesicular texture. Vesicles range in shape from spherical to elongated and in size from ~1mm to more than 1 cm. Basalts are most commonly vesicular. coarse-grained, Coarse-grained textures generally indicate magmas that slowly cooled deep underground. Slow cooling gives crystals enough time to grow to easily seen sizes glassy, f a rock looks like a block of (colored) glass, with no visible mineral crystals, it has a glassy texture. and porphyritic. Many rocks with an overall fine-grained texture display scattered minerals that are more than 1 mm across. This porphyritic texture indicates that the magma sat and cooled a bit below the Earth's surface, thus giving time for the large crystals to grow, before erupting onto the surface and cooling very quickly. * Know the basic differences between granitic (felsic) Felsic: Usually white or another light colour. Can contain Quartz, biotite, muscoviite, amphibole, k-feldspar amongst other things. Very sticky magma, it erupts violently - Mt St Helens style. No olivine or pyroxene (usually). igneous rocks and basaltic (mafic) igneous rocks. Mafic: usually black or dark brown, contains olivine, clinopyroxene, orthopyroxene, plagioclase, or combination's of the above. When molten this is usually very runny, it erupts gently, creating shield volcanoes, e.g. Hawaii. Which is found in abundance is oceanic crust? Which is found in abundance in continental crust? Mafic * Know which igneous rock is popular as a building material. Granite * Know the differences between mechanical any of the various weathering processes that cause physical disintegration of exposed rock without any change in the chemical composition of the rock:. and chemical weathering. the erosion or disintegration of rocks, building materials, etc., caused by chemical reactions (chiefly with water and substances dissolved in it) rather than by mechanical processes. Be able to define and discuss each. * Know the different physical processes that mechanically weather rock material (e.g., frost The weathering process caused by cycles of freezing and thawing of water in surface pores, cracks, and other openings. Alternate or repeated cycles of freezing and thawing of water contained in materials; the term is especially applied to disruptive effects of this action. wedging, Ice wedging is defined as mechanical weathering by which rock are, over time, broken by the expansion of water that freezes in a rock's joints, pores, or bedding plans. This expansion forces rocks apart. Ice wedging may also be referred to as frost wedging. sheeting, Massive igneous rocks (granite) form in hi pressure. Pressure is released as overlying rock is eroded off. Release causes expansion, forming SHEET or EXFOLIATION JOINTS parallel to Earth's surface biological activity). Likewise, be able to identify the processes that chemically weather rock material (e.g., oxidation, decomposition [in the presence of acid], hydrolysis [in the presence of water]). * Know the differences between detrital They form as sediment grains (detritus or clasts), weathered and eroded from pre-existing rocks, are deposited as layers in low-lying areas such as valleys, lakes, or an ocean basin. and chemical sedimentary rocks. Chemical sedimentary rocks form by the precipitation of minerals from water (this process may or may not involve the actions of organisms). In contrast to the clastic textures of the rocks discussed above, chemical sedimentary rocks have crystalline textures. What physical property is used principally to classify detrital sedimentary rocks? The simple ideal model for the evolution of sedimentary rocks says there are three end products, three attractors, that all sedimentary processes are working to reach - quartz sandstone, shale, and limestone. * Name some common minerals found together in detrital sedimentary rocks. Quartz, * Name the most abundant chemical sedimentary rock found on earth. Limestone * What are evaporite deposits? it is a mineral that was dissolved in water and when the water dries up the mineral is deposited. Where do these typically form? In bodies of water * In terms of sedimentary rocks, define these terms: lithification, the process or processes by which unconsolidated materials are converted into coherent solid rock, as by compaction or cementation. cementation, the binding together of particles or other things by cement. strata, a layer of material, naturally or artificially formed, often one of a number of parallel layers one uponanother: a stratum of ancient foundations. and fossils. the remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock. * What is metamorphism? alteration of the composition or structure of a rock by heat, pressure, or other natural agency. * Name and describe the two basic types of metamorphism (i.e., contact metamorphism due to contact with or proximity to an igneous intrusion and regional). metamorphism affecting rocks over an extensive area as a result of the large-scale action of heat and pressure. * Be able to identify the agents of metamorphism.
HEAT contributes to the process in two ways. First, atoms may combine differently at different temperatures. This means that a mineral stable at one temperature might become unstable at a higher (or lower) temperature and be converted to a different mineral with a more stable atomic structure. This may or may not involve changing the exact elemental composition. Second, heat makes practically all chemical reactions go faster, meaning that mineral transformations are much easier at higher temperature.
PRESSURE also has two effects. As with heat, it can control which minerals or forms of minerals are stable. Some minerals may be converted to minerals with similar composition but different atomic packing simply because pressure is increased. The exact nature of the pressure is not important in this case, only the amount. Thus the CONFINING (or LITHOSTATIC) PRESSURE created by deep burial of rocks under sediment may have this effect as well as the DIRECTED (or DIFFERENTIAL) PRESSURE produced by converging plates. The second effect of pressure is to reorient minerals with linear or platy structure or to create a preferred orientation of them as they form. Thus elongate minerals such as amphiboles, or platy minerals such as clays or micas tend to align themselves parallel to each other when under pressure. This only happens when there is directed pressure; confining pressure does not accomplish it. The diagram illustrates the effect. A texture of this sort in a metamorphic rock is called FOLIATION and the rocks are said to be FOLIATED.
FLUIDS serve only to speed up other metamorphic processes, or perhaps even allow them to happen at all. Chemical reactions require water, and most proceed much faster as the amount of water goes up. Dissolved ions in the fluid also make those mineral transformations that require chemical changes in the minerals to occur, whether by supplying needed ions or flushing away excess ones. * What is foliation in metamorphic rocks? A foliated metamorphic rock is a rock which is formed by alternating layers of minerals. This rock is formed after environmental changes in temperature or due to pressure; * Know the differences between foliated foliated rocks show banding throughout. The banding is caused by pressure that is placed upon the rocks as they form. and non-foliated metamorphic textures. Non foliated rock has no banding or layers. Examples of non foliated rock are marble and quartzite. Be able to give examples of each (i.e., gneiss is foliated; quartzite is non-foliated; etc.).

Landscapes Fashioned by Water (Chapter 3)

* What is mass wasting? Mass wasting, also known as slope movement or mass movement, is the geomorphic process by which soil, sand, regolith, and rock move downslope typically as a mass, largely under the force of gravity, but frequently affected by water and water content as in submarine environments and mudslides.What force is primarily responsible for mass wasting? Gravity, the shape of the slpe and water * Have a basic understanding of the hydrologic cycle. . the natural sequence through which water passes into the atmosphere as water vapor, precipitates to earth in liquid or solid form, and ultimately returns to the atmosphere through evaporation. * Know the various “loads” in a river (i.e., dissolved load Dissolved load is the term for material, especially ions from chemical weathering, that are carried in solution by a stream. The dissolved loadcontributes to the total amount of material removed from a catchment., suspended load, Suspended load is the portion of the sediment that is carried by a fluid flow which settle slowly enough such that it almost never touches the bed. It is maintained in suspension by the turbulence in the flowing water and consists of particles generally of the fine sand, silt and clay size. and bed load the sand, gravel, boulders, or other debris transported by rolling or sliding along the bottom of a stream. river or stream for taking a bed load sample. Bed load is the sediment that is transported in a stream by rolling, sliding,). What size particles are typically carried in each type of load? * Be able to define these terms: stream discharge, The depth and swiftness of a stream affect the communities of macroinvertebrates and other organisms that are able to live in the stream.stream gradient, is the grade measured by the ratio of drop in elevation of a stream per unit horizontal distance, usually expressed as feet per mile or metres per kilometre. longitudinal profile. A graphic presentation of elevation vs. distance; in channel hydraulics it is a plot of water surface elevation against upstream to downstream distance. * Be able to determine stream gradient using the following formula: (change in elevation [in meters]) divided by (change in horizontal distance of flow [in kilometers]). For example, if a stream decreases in elevation 100 meters over a flow distance of 500 kilometers, then the stream gradient is 100 meters/500 kilometers = 0.2 m/km. * Know the difference between stream capacity The capacity of a stream or river is the total amount of sediment a stream is able to transport. This measurement usually corresponds to the stream power and the width-integrated bed shear stress across section along a stream profile. and stream competence. The maximum particle size that a stream can carry * Define base level. The base level of a river or stream is the lowest point to which it can flow, often referred to as the 'mouth' of the river. For large rivers, sea level is usually the base level, but a large river or lake is likewise the base levelfor tributary streamsWhat is the ultimate base level? For large rivers, sea level is usually the base level, but a large river or lake is likewise the base level for tributary streams. All rivers and streams erode toward sea level, which is also known as the "ultimate base level.” * In terms of stream erosion, what is the difference between a V-shaped valley (eroding well above base level) V shaped only means that it was eroded by a swiftly running river - and the river cut down through. Had the valley been glaciated - full of ice - at any point, it wold be U shaped. What you can sometimes see is a fairly U shaped valley which was later cut in the middle in a V shape because once the ice melted, the valley was further eroded by a river. and wide river valleys with meandering rivers A meander is formed when the moving water in a stream erodes the outer banks and widens its valley and the inner part of the river has less energy and deposits what it is carrying. (eroding very close to base level)? * Be able to define the following terms: floodplain, an area of low-lying ground adjacent to a river, formed mainly of river sediments and subject to flooding. cutoff, cutoff occurs when a meander bend in a river is breached by a chute channel that connects the two closest parts of the bend. oxbow lake, a curved lake formed at a former oxbow where the main stream of the river has cut across the narrow end and no longer flows around the loop of the bend. cut bank, A cut bank, also known as a river cliff or river-cut cliff, is the outside bankof a water channel (stream), which is continually undergoing erosion. and point bar. an alluvial deposit that forms by accretion on the inner side of an expanding loop of a river. * Know and be able to describe the four basic stream drainage patterns (i.e., dendritic, was a tree-like trace of the streams on a map that resulted from uniform surface control of the development of stream channels. The bedrock is of equal resistance to erosion. radial, a drainage system is the pattern formed by the streams, rivers, and lakes in a particular drainage basin. They are governed by the topography of the land, whether a particular region is dominated by hard or soft rocks, and the gradient of the land. ... rectangular, the drainage pattern of streams that make many right-angle bend and trellis forms when tributaries join the main river at right angles.it froms in a ridge-and-valley landscape). In what types of geologic conditions do each tend to form? Which is the most common? * Know the difference between an aquifer a body of permeable rock that can contain or transmit groundwater. and an aquitard. the shallowest aquifer at a given location is unconfined, meaning it does not have a confining layer (an aquitard or aquiclude) between it and the surface. The term "perched" refers to ground water accumulating above a low-permeability unit or strata, such as a clay layer. * Know the different zones of groundwater (i.e., zone of saturation, The water table is defined as the level beneath the Earth's surface below which all pore spaces are filled with water, and above which the pore spaces are filled with air. The zone of saturation is the area beneath the water table where all pore spaces are completely filled with water. unsaturated zone, The unsaturated zone is the portion of the subsurface above the groundwater table. The soil and rock in this zone contains air as well as water in its pores. belt of soil moisture The upper subdivision of the zone of aeration limited above by the land surface and below by the intermediate belt; this zone contains plant roots and water available for plant growth. Also known as belt of soil moisture; discrete film zone; soil-water belt; soil-water zone; zone of soil water.). Be able to describe each (generally) * What is the water table? the level below which the ground is saturated with water. * Know the difference between porosity Porosity is the quality of being porous, or full of tiny holes. Liquids go right through things that have porosity. Go back far enough and you'll find thatporosity stems from the Greek word poros for "pore," which means “passage.” So something with porosity lets things through. and permeability in soil/rock. the state or quality of a material or membrane that causes it to allow liquids or gases to pass through it. * Understand and be able to define the following: hot springs, a spring of naturally hot water, typically heated by subterranean volcanic activity geysers, a hot spring in which water intermittently boils, sending a tall column of water and steam into the air. cone of depression, A cone of depression occurs in an aquifer when groundwater is pumped from a well. In an unconfined aquifer (water table), this is an actualdepression of the water levels. In confined aquifers (artesian), the cone of depression is a reduction in the pressure head surrounding the pumped well. and land subsidence. Land subsidence is a gradual settling or sudden sinking of the Earth's surface owing to subsurface movement of earth materials. In most cases, from where does the heat come to “power” hot springs and geysers? The heat of these rocks comes from the molten rocks below. Eventually, the intense heatboils the water, which then turns into steam. This increases the pressureinside the crevice as bubbles of steam build up. Finally, the pressure is strong enough to shoot the water and steam upwards and out through avent, high into the air. * What is an artesian well? Water may even reach the ground surface if the natural pressure is high enough, in which case the well is called a flowing artesian well. Under what geologic conditions are these wells found? an inclined aquifer sandwiched between impervious rock layers above and below that trap water in it. * Karst topography describes topography that evidences the erosional effects of groundwater. What are some topographic evidences of karst topography? * Know the difference between stalactites a tapering structure hanging like an icicle from the roof of a cave, formed of calcium salts deposited by dripping water. and stalagmites. a mound or tapering column rising from the floor of a cave, formed of calcium salts deposited by dripping water and often uniting with a stalactite. Where do they form (i.e., in the zone of saturation or the unsaturated zone)? * How do sinkholes form? A sinkhole, also known as a sink-hole,[1] sink, swallow hole, shakehole,[2] swallet or doline, is a depression or hole in the ground caused by some form of collapse of the surface layer. Some are caused by karst processes—for example, the chemical dissolution of carbonate rocks[3] orsuffosion processes.[4]
Glaciers (Chapter 4) * Know how much of the earth’s land area was covered by glaciers during the last ice age. 30% How much of the earth’s surface is covered by glaciers today? 10% * What is the division of geologic time in which many geologists place the last ice age? Geologic time is the 4.6 Billion year history of Earth, from its origin to the present, as inferred from the rock record, both on Earth and the Moon, and the geochemical make-up of those two bodies. * Know the location of the world’s major ice sheets today. antartic * Know the different types of glaciers (i.e., valley [alpine], glacier usu. originating in a cirque at a valley head or in a plateau ice cap and flowing downward between the walls of a valley ice sheets, a permanent layer of ice covering an extensive tract of land, esp. a polar region. piedmont, a type of glaciation characteristic of Alaska; large valley glaciers meet to form an almost stagnant sheet of ice ice caps) is an ice mass that covers less than 50 000 km² of land area (usually covering a highland area). Masses of ice covering more than 50 000 km² are termed an ice sheet. and be able to describe each (generally). Give examples of each. * Know the difference between the zone of accumulation The annual Glacier equilibrium line separates the accumulation and ablation zone annually. The accumulation zone is also defined as the part of a glacier's surface, usually at higher elevations, on which there is netaccumulation of snow, which subsequently turns into firn and then glacier ice. and the zone of wastage in a glacier. that part of a glacier where more ice is removed (ablates) from the glacier than is added (accumulates) - over a period of 365 days. What is the “budget of the glacier”? The balance in a glacier between the input of snow and firn, that is, accumulation, and the loss of ice due to melting, evaporation, sublimation, and calving, that is, ablation. A glacier grows where the budget is positive and retreats when it is negative.
If accumulation exceeds wastage, what happens to the glacier? It advances What about if wastage exceeds accumulation? It receeds What if the two are equal? It stops moving * Be able to describe the major flow mechanisms operating in a glacier (i.e., plastic flow deformation of a material that remains rigid under stresses of less than a certain intensity but that behavesunder severer stresses approximately as a Newtonian fluid. and basal slip When a glacier moves because it's ice touches the ground [i.e., slipping along its lower surface where it contacts the land surface]). * Know the difference between abrasion the process of scraping or wearing away and plucking. is a glacial phenomenon that is responsible for the erosion and transportation of bedrock especially large joint blocks. ... * Name and describe the erosional features in glacial terrain: glacial striations, Long scratches in bedrock caused by a moving glacier glacial trough, a valley shaped by valley glaciers and ice streams within ice sheets that has a distinct trough form hanging valleys, is a valley that has a higher floor than the main valley cirques, A bowl shaped depression in the side of a mountain with steep sides arêtes, A ridge that separates two adjoining cirques horns, and fiords. * Name and describe the depositional features in glacial terrain: lateral are parallel ridges of debris deposited along the sides of a glacier and medial moraines, is a ridge of moraine that runs down the center of a valley floor. end moraines, Multiple erratics on the terminal moraine of the Okanagan Lobe. Cascade mountains in the background. End moraines, or terminal moraines, are ridges of unconsolidated debris deposited at the snout or end of the glacier. ground moraines, a moraine deposited beneath a glacier and back from its edge or end eskers, a long ridge of gravel and other sediment, typically having a winding course, deposited by meltwater from a retreating glacier or ice sheet. kames, a steep-sided mound of sand and gravel deposited by a melting ice sheet. drumlins, a low oval mound or small hill, typically one of a group, consisting of compacted boulder clay molded by past glacial action kettles, are believed to form when a block of ice left by a glacier becomes covered by sediments and later melts, leaving a hollow. and outwash plains/valley trains. is a plainformed of glacial sediments deposited by meltwater outwash at the terminus of a glacier. * What is the zone of fracture in a glacier? is a linear oceanic feature--often hundreds, even thousands of kilometers long--resulting from the action of offset mid-ocean ridge axis segments. They are a consequence of plate tectonics. How deep is this zone? * Describe glacial calving. The ice sheets lose material by several processes, including surface melting, evaporation, wind erosion (deflation), iceberg calving, and the melting of the bottom surfaces of floating ice shelves by warmer seawater. Where does it occur? Where glaciers meet the sea * Know the definitions of the terms glacial drift, is the loose and unsorted rock debris or earth distributed by glaciers and glacial melt waters till, is unsorted glacial sediment and stratified drift. Sediments deposited by glacial meltwater that are sorted and layered; a major subdivision of glacial drift that includes river, lake, and marine How do these relate to one another?

Deserts (Chapter 4)

* What is the difference between desert and steppe climates? A desert is a dry, often sandy region of little rainfall, extreme temperatures, and sparse vegetation. A steppe is a grassland without trees. It may be a semi-desert or covered with grass or shrubs. The term is also sometimes used to describe a climate that is to dry to support trees. A prairie can be considered a steppe. * What is the most important erosional agent in a desert environment? The most important erosional agent in Deserts is the water. It is because water is the most resourceful out of the whole entire world. Without water nothing could live. * Know the geographic distribution of deserts around the world. See SmartFigure 4.24 on page 137. How much of the world is covered by deserts? 33% * Be able to define the following terms: ephemeral stream, a stream that flows only briefly during and following a period of rainfall in the immediate locality alluvial fan, is a fan- or cone-shaped deposit of sediment crossed and built up by streams. bajada, consists of a series of coalescing alluvial fans along a mountain front. and playa lake. are round hollows in the ground in the Southern High Plains of the United States. They are ephemeral, meaning that they are only present at certain times of the year. * What is deflation? the erosion of soil as a consequence of sand, dust, and loose rocks being removed by the wind How does this relate to desert pavement? * What is loess? a loosely compacted yellowish-gray deposit of windblown sediment of which extensive deposits occur, e.g., in eastern China and the American Midwest. What is its origin? * Describe sand dunes and how they form. a ridge of sand created by the wind; found in deserts or near lakes and oceans

Plate Tectonics (Chapter 5)

* Who proposed the hypothesis of continental drift? Alfred Wagener What did he call his proposed supercontinent? pangaea * What physical and geological evidences support continental drift? Rock distribution, mountain ranges, fossil distributions, and evidence of glaciation * Why was continental drift largely rejected by the scientific community in the early 20th century? One reason for their skepticism was the difficulty one encountered in attempting to "fit" continents of the Northern Hemisphere back together. But their biggest objection was to the mechanism Wegener proposed for how the continents had "drifted"!

* Know what glossopteris meaning "tongue", because the leaves were tongue-shaped) is the largest and best-known genus of the extinct order of seed ferns known as Glossopteridales and mesosaurus an extinct small aquatic reptile of the early Permian period, with an elongated body, flattened tail, and a long narrow snout with numerous needlelike teeth are. How are these important to the continental drift hypothesis? 2 continents used to be joined together * Be able to define lithosphere the rigid outer part of the earth, consisting of the crust and upper mantle. and asthenosphere. the upper layer of the earth's mantle, below the lithosphere, in which there is relatively low resistance to plastic flow and convection is thought to occur. How do the two differ? is how the materials in these layers can flow. Rocks in the lithosphere are "rigid", meaning that they can bend but they cannot flow. Rocks in the asthenosphere are "plastic", meaning that they can flow in response to deformation. * What are the relative densities of oceanic and continental crust continental is 2.7 and the oceanic is 2.9 . Oceanic is denser(i.e., which is denser)? * Be able to define the following: divergent boundary, is a linear feature that exists between two tectonic plates that are moving away from each other. convergent boundary, A subduction zone is formed at a convergent plate boundary when one or both of the tectonic plates is composed of oceanic crust. The denser plate, made of oceanic crust, is subducted underneath the less dense plate, which can be either continental or oceanic crust. and transform fault boundary. also known as conservative plate boundary since these faults neither create nor destroy lithosphere, is a type of fault whose relative motion is predominantly horizontal in either sinistral or dextral direction Know what happens at each of these boundaries in terms of plate interaction, seafloor production/destruction, volcanism, and earthquake activity. Also, know what kinds of geologic features form at each type of boundary. Finally, how does the presence of both divergent and convergent boundaries help explain the fact that the earth is neither growing in size nor shrinking in size? * What is a subduction zone? are sites of high rates of volcanism, earthquakes, and mountain building. Orogenesis, or mountain-building, occurs when large pieces of material on the subducting plate (such as island arcs) are pressed into the over-riding plate or when subhorizontal contraction occurs in the over-riding plate. * What is a hot spot? a small area or region with a relatively hot temperature in comparison to its surroundings. How are these evidence of plate tectonics? * Know what the Pacific Ring of Fire is. They are formed due to subduction zones of three main active tectonic plates namely the Eurasian Plate, Pacific Plate, and the Indo-Australian Plate. * Be able to name and describe the forces that drive plate motion (i.e., slab pull, is the portion of motion of a tectonic plate that can be accounted for by its subduction. Plate motion is partly driven by the weight of cold, dense plates sinking into the mantle at trenches. This force and slabsuction account for almost all of the force driving plate tectonics. ridge push, or sliding plate force is a proposed mechanism for plate motion in plate tectonics. Because mid-ocean ridges lie at a higher elevation than the rest of the ocean floor, gravity causes the ridge to pushon the lithosphere that lies farther from the ridge and mantle drag). Hot mantle that spreads out laterally beneath the ridges or at hot spots may speed up or slow down the plates, a force known as mantle drag. However, the mantle flow pattern at depth does not appear to be reflected in the surface movements of the plates * What is a mid-ocean ridge? a long, seismically active submarine ridge system situated in the middle of an ocean basin and marking the site of the upwelling of magma associated with seafloor spreading. An example is the Mid-Atlantic Ridge. Know the average rate of seafloor spreading at an ocean ridge. * Know how age of the ocean crust and depth of ocean sediment relate to distance from the mid-ocean ridge. * Who were the scientists who first studied (comprehensively) magnetic striping in oceanic crust? Bernard Brunhes in France and Motonari Matuyama What did they find?

Geologic Time (Chapter 8)

* According to Lutgens and Tarbuck (and other secular geologists), how old is the earth? 4.5 billion years * Define uniformitarianism Uniformitarianism is the assumption that the same natural laws and processes that operate in the universe now have always operated in the universe in the past and apply everywhere in the universe.and catastrophism. Catastrophism is the theory that the Earth has been affected in the past by sudden, short-lived, violent events, possibly worldwide in scope. How do they differ? Who is responsible for proposing the idea of uniformitarianism? James Hutton, Charles Lydell * What is an unconformity? a surface of contact between two groups of unconformable strata. * Be able to name and describe the three basic types of unconformities (i.e., angular unconformity, unconformity where horizontally parallel strata of sedimentary rock are deposited on tilted and eroded layers, producing an angular discordance with the overlying horizontal layers. The whole sequence may later be deformed and tilted by further orogenic activity. disconformity, a break in a sedimentary sequence that does not involve a difference of inclination between the strata on each side of the break. and non-conformity). failure or refusal to conform to a prevailing rule or practice. * Be able to describe the principle of superposition, the principle that in a series of stratified sedimentary rocks the lowest stratum is the oldest the principle of original horizontality, was proposed by the Danish geological pioneer Nicholas Steno (1638–1686). This principle states that layers of sediment are originally deposited horizontally under the action of gravity.the principle of cross-cutting relationships, Originally developed by James Hutton in Theory of the Earth (1795) and embellished upon by Charles Lyell in Principles of Geology (1830), theprinciple of cross-cutting relationships states that the geologic feature which cuts another is the younger of the two features.and the principle of fossil succession. In a stratigraphic sequence, different species of fossil organisms appear in a definite order; once a fossil species disappears in a sequence of strata, it never reappears higher in the sequence. * Name the conditions that favor fossil preservation. Rapid burial, and possession of skeleton, or shell. Low oxegyn * Be able to describe the different types of fossils, premineralization, Permineralization is a process of fossilization in which mineral deposits form internal casts of organisms. Carried by water, these minerals fill the spaces within organic tissue. molds and casts, Cast and mold are a type of fossilization where the physical characteristics of organisms are impressed onto rocks, especially coarse porous rocks such as sandstones. carbonization fossils, Carbonization refers to fossils being preserved as dark-colored, flattened, carbon-rich films. Most fossil leaves in the rock record have been carbonized. But, any fossil that's been preserved as a dark, flattened film can be called carbonized. and trace fossils. Trace fossils, also called ichnofossils, are geological records of biological activity. Trace fossils may be impressions made on the substrate by an organism: for example, burrows, borings, urolites, footprints and feeding marks, and root cavities * What is an index fossil? a fossil that is useful for dating and correlating the strata in which it is found. What are the essential characteristics of an index fossil? * Define correlation. mutual relationship or connection between two or more things. How are fossils used to correlate sedimentary rocks across large geographical areas? * Define parent elements A Parent Element is a radioactive element which freely decays into a new substance. and daughter elements is the new product that decays from the parent element. This therefore means that the parent element determines the outcome of the daughter element. in terms of radioactive decay processes. * Be able to describe the three basic types of radioactive decay: alpha, beta, and electron capture. You must be able to speak of these in terms of the change in atomic number and atomic mass when the parent element decays. For example, alpha particle decay reduces the atomic number of a parent element by 2 and reduces the atomic mass by 4. See Figure 8.17 on page 284. * Know the half-lives of common radioisotopes such as uranium-238, uranium-235, potassium-40, rubidium-87, and carbon-14. See page 286 for assistance. * Which rock types can and cannot be dated using radiometric methods? Sedimentary rocks * If given the half-life of a radioisotope AND the number of years that have passed since radioactive decay processes began, be able to determine 1) the number of half-lives that have passed and 2) the amount of the parent element remaining. For instance, if you are told the half-life of carbon-14 is 6,000 years and the decay process started 6,000 years ago, then you could say that 1) only one half-life has passed and 2) about 50% or one-half of the parent isotope remains. Use SmartFigure 8.19 on page 285 for assistance. * Know the basic structure of the geologic time scale. You do not have to memorize the scale, but you need to know what eons, an indefinite and very long period of time, often a period exaggerated for humorous or rhetorical effect.eras, a long and distinct period of history with a particular feature or characteristic. periods, belonging to or characteristic of a past historical time, esp. in style or design. and epochs a period of time in history or a person's life, typically one marked by notable events or particular characteristics. are, and how long they are relative to one another
 Eons: Longest subdivision; based on the abundance of certain fossils
 Eras: Next to longest subdivision; marked by major changes in the fossil record
 Periods: Based on types of life existing at the time
 Epochs: Shortest subdivision; marked by differences in life forms and can vary from continent to continent. T (i.e., eons are longer than periods, epochs are shorter than eons, etc.). * Know the basic definitions of the three most recent geologic eras: Paleozoic, meaning "ancient life" ) is the earliest of three geologic eras of the Phanerozoic Eon, spanning from roughly 541 to 252.2 ... Mesozoic, The Mesozoic era /mɛzɵˈzoʊɪk/ is an interval of geological time from about 252 to 66 million years ago. and Cenozoic. meaning "new life", from Greek καινός kainos "new", and ζωή zoe"life"[1]) is the current and most recent of the three Phanerozoic geological eras, following the Mesozoic Era and covering the period from 66 million years ago to the present. What do each of these mean (i.e., Mesozoic means “middle life”)? * What is the Precambrian? of, relating to, or denoting the earliest eon, preceding the Cambrian period and the Phanerozoic eon How much time do secular geologists say the Precambrian covers? 1,000 billion years * What are some difficulties in dating the geologic time scale? Deducing the events of five hundred million years ago is difficult, as evidence comes exclusively from biological and chemical signatures in rocks and very sparse fossils * Who was James Ussher? James Ussher (sometimes spelled Usher, 4 January 1581 – 21 March 1656) was Church of Ireland Archbishop of Armagh and Primate of All Irelandbetween 1625 and 1656. He was a prolific scholar, who most famously published a chronology that purported to establish the time and date of thecreation as the night preceding Sunday, 23 October 4004 BC, according to the proleptic Julian calendar.How old did he say the earth is? Bishop Ussher dates the creation of the world at 4004 BC
Morris Textbook (Chapters 1–2, 4–5, and 7): * How are human beings limited in their ability to interpret the past, according to Morris? * Does the Bible interpret the Hebrew word “yom”? literal day If so, what does “yom” mean? * Know the difference between young-earth creationists and old-earth creationists? On what major point do they differ? * What is meant by “overlapping days” in Genesis? Each day overlapped onto the days before it and after it. Is this an old-earth or young-earth viewpoint? Old earth What are some weaknesses in it? * How does Morris use tree rings and Niagara Falls in Chapter 4 to make his point about uncertainty in the geologic past? In what ways can Niagara Falls be used to support a young-earth model? * Know and understand (generally) the four assumptions that underlie radiometric dating methods. Isolation of the rock from its environment. The daughter product. Decay rate of percent into daughter. Earth is at least old enough for the present amount of lead in a specimen. * How does the supposed radiometric age of the Cardenas Basalt in the Grand Canyon as compared to the supposed radiometric age of the basalts on the canyon rim (i.e., the plateau basalts) bring into question the geologic history of the Grand Canyon? * What are radiohalos, or pleochroic halos are microscopic, spherical shells of discolouration within minerals such as biotite that occur in granite and other igneous rocks. and how do they support a young earth? * Why is carbon-14 dating not reliable for materials more than a couple thousand years old? Lacks the ability to identify small particals * How does helium in the atmosphere help explain a young earth? * How do old-earth geologists and young-earth geologists differ on the idea of “remnant magnetism” and magnetic reversals? * What are the input and output processes related to the salinity (i.e., salt concentrations) in the modern ocean? How do creation scientists use the salinity of the ocean to bolster the case for a young-earth? * In general, how does erosion of the continental rocks and deposition of the resulting sediment in the ocean support a young-earth model? +