ERTH 31O

What type of plate boundary is forming the Himalaya Mountains, the tallest in the world?? Select one: a. Continent to continent convergent b. Divergent c. Ocean to continent convergent d. Ocean to ocean convergent e. Transform

a. Continent to continent convergent

Refer to the video on Classifying Igneous Rocks. Which of the following statements best describes a plutonic igneous rock? Select one: a. It cooled slowly, so it is coarse grained (has large-sized crystals). Correct b. It cooled relatively quickly, so it is fine grained (has small-sized crystals). c. It cooled so quickly that no crystals formed (it is a glass).

a. It cooled slowly, so it is coarse grained (has large-sized crystals). Correct

Chert is a rock that tells us about the geologic history of San Francisco. According to this web page: http://www.nps.gov/prsf/naturescience/chert.htm, where did the chert form? Select one: a. It formed at the bottom of the ocean, when the plate was near the equator. It was then transported here by plate movements. Correct b. It formed at the bottom of the ocean at a time when the plate was fairly near to San Francisco. c. It formed along a mid-ocean ridge, when the plate was located to the north (near Alaska). It was then transported here by plate movements. d. It formed at the bottom of the ocean when the plate was near southern California. The plate then moved here along a transform fault (e.g., the San Andreas).

a. It formed at the bottom of the ocean, when the plate was near the equator. It was then transported here by plate movements. Correct

Clastic sedimentary rocks are best described as (for additional info on sedimentary rocks: https://www.youtube.com/watch?v=uozyWZ6XQzM) Select one: a. Made up of broken pieces eroded from other rocks (example: sandstone) Correct b. Formed by the cooling of molten (liquid) rock. c. Made up of pieces of organisms shells (example: limestone) d. Formed deep in the interior of Earth

a. Made up of broken pieces eroded from other rocks (example: sandstone) Correct

The lava lamp illustrates which important internal Earth process? For a super helpful explanation, see: https://www.youtube.com/watch?v=DL3Ez9bxMTo Select one: a. convection b. conduction c. convergence d. divergence e. radiation

a. convection

Refer to the sequence of events shown below, which explains the development of an unconformity (gap in the record of geologic time). What is the name of an erosion surface that separates two sets of sedimentary layers with parallel bedding planes? Unconformities: https://www.youtube.com/watch?v=DNcYBLG3TBo Select one: a. disconformity Correct b. angular unconformity c. nonconformity

a. disconformity

Again, examine Figure 2.18 and the blue arrows that show relative motion of plates adjacent to plate boundaries! You can see similar arrows here, except they are black: http://academic.emporia.edu/aberjame/student/june3/767june.html Tension is a force that you feel if you hang by your arms from a pull up bar. Which type of plate boundary is characterized by tensional forces (or stresses)? Select one: a. divergent boundary b. convergent boundary (subduction type) c. convergent boundary (continental collision type) d. transform boundary

a. divergent boundary

Refer to the map of seafloor age below. Where in the oceans is the oldest ocean crust found? Select one: a. in an oceanic trench where it's about to be subducted b. under a continental shelf at a passive margin c. the abyssal plain d. mid-ocean ridges e. all ocean crust is the same age

a. in an oceanic trench where it's about to be subducted

Seismic waves travel more easily through solid rocks... because those materials can ring like a bell! Consider the attached plot which shows seismic wave velocity (speed) measured at increasing depths below the earth's surface. You can see the the seismic wave velocity (speed) changes. This is because the nature of the rocks is also changing with depth! Remember: higher wave velocities mean that those elements transmit the waves better—like tuning forks! In general, seismic wave velocities tend to _____________ with depth due to the trend towards increasing __________________. Select one: a. increase, density b. increase, temperature c. decrease, density d. decrease, temperature

a. increase, density

Gold _____________ because______________. Select one: a. is a mineral, it meets all 5 requirements b. is not a mineral, it does not have an orderly internal structure c. is not a mineral, it is organic d. is not a mineral, it does not have a definite chemical composition

a. is a mineral, it meets all 5 requirements

Shown below is a figure that describes the elevation of earth's surface relative to sea level. (Higher elevations are warm in color and lower elevations are cooler in color.) In general, there is a distinct contrast in surface elevation (or topography!) between the ocean basins and the continents. Please assume that this effect is a result of buoyancy. Study the elevation differences and identify any patterns. If the elevation differences are due to buoyancy, different lithospheric plates appear to have different buoyancies, yes? Imagine two blocks that are the same size... one wooden and one styrofoam. Which will float higher on the asthenosphere? Which lithospheric plates are relatively more dense? Select one: a. oceanic b. continental c. asthenospheric d. mohorovicic

a. oceanic

Below is a map of the major plate boundaries (several similar figures also appear in your text!) Consider the global earthquake distribution in relation to the location and type of plate boundary. Here, earthquakes are colored points. The location of the point is the location of the earthquake epicenter. In this figure, the depth of each earthquake is indicated by the color of the point. Use the explanation to the right of the figure to assess which earthquakes are relatively deep and which are relatively shallow. Along divergent plate boundaries, earthquakes tend to be: Select one: a. shallow b. shallow to intermediate c. shallow to deep

a. shallow

According to the website http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/cardat.html and the Table below, what would be the most appropriate material for carbon dating? Select one: a. Gypsum beds preserved in a sand from an evaporated lake b. Bone found in a clay bed overlying a 30,000 year old lava flow c. 100 million year old granite of the Sierra Nevada d. Well sorted sediment preserved in cross beds from ancient sand dunes

b. Bone found in a clay bed overlying a 30,000 year old lava flow

Carefully study the cross-section below (and read Chapter 5!) which shows a generalized model for the distribution of various igneous rocks in the lithosephere. Overall, this model describes the lithosphere very well. The key observation to remember is that one typically finds felsic, intermediate, or mafic igneous rocks in specific plate tectonic settings. Which of the following statements is most true?Select one: a. Continental lithosphere is more buoyant because it consists mostly of mafic igneous rocks b. Continental lithosphere is more buoyant because it consists mostly of felsic igneous rocks Correct c. Ocean lithosphere is more buoyant because it consists mostly of mafic igneous rocks d. Ocean lithosphere is more buoyant because it consists mostly of felsic igneous rocks

b. Continental lithosphere is more buoyant because it consists mostly of felsic igneous rocks Correct

Igneous rocks are best described as (see Ch. 5.1-5.2) Rock Types: Note: Rocks are aggregates of minerals and are classified (named) based on how the rock formed. Igneous Rocks: https://www.youtube.com/watch?v=PrN7jygu4cQ Classifying igneous rocks: https://www.youtube.com/watch?v=Zbz4e-9pjY4 Identifying Igneous Minerals and Rocks: https://www.youtube.com/watch?v=jsWvqWzFOXk Sedimentary Rocks: https://www.youtube.com/watch?v=uozyWZ6XQzM Metamorphic Rocks: https://www.youtube.com/watch?v=Ncr-46YX-N0 Select one: a. Made up of broken pieces eroded from other rocks (example: sandstone) b. Formed by the cooling of molten (liquid) rock. Correct c. Made up of pieces of organisms shells (example: limestone)

b. Formed by the cooling of molten (liquid) rock. Correct

Volcanic activity occurs where heat is able to reach near to the earth's surface... Heat can travel along faults or by way of plumes in the earth's mantle. This includes a few different geologic settings... Which of the following features is not generally associated with volcanic activity? Select one: a. In subduction zones b. In a craton c. In divergent zones d. Hotspots

b. In a craton

Check out your reading for details on magnetic reversals... How did we discover that these occur? Where is the best geologic evidence for these reversals? What is the importance of magnetic reversals to the theory of plate tectonics? Select one: a. It causes earthquakes on the seafloor. b. It provides evidence for seafloor spreading. c. It causes volcanic eruptions underwater. d. It is associated with mass extinction events. e. It explains times of rapid change on the Earth's surface.

b. It provides evidence for seafloor spreading.

Now look over at the east coast... what kind of continental margin is the east coast of the United States? Select one: a. Active b. Passive c. Marginal d. Atlanticus e. Pacificus

b. Passive

Below is a list of methods for relative and numerical dating of Earth events. Which method is a numerical method (also called "absolute" method)? Select one: a. Fossils b. Radiometric dating Correct c. Principal of horizontality d. Principal of cross-cutting

b. Radiometric dating Correct

REVIEW QUESTION: Which statement best describes the relationship between temperature and depth in the earth. Select one: a. The temperature is hotter at the surface and cooler at depth. b. The temperature is cooler at the surface and increases most rapidly in the upper 50 km. Correct c. There is no change in temperature with depth.

b. The temperature is cooler at the surface and increases most rapidly in the upper 50 km. Correct

Serpentinite is the state rock of California, and widely abundant in the Bay Area. Visit the following website to read about serpentinite, http://www.conservation.ca.gov/cgs/information/publications/cgs_notes/note_14. What type of rock is the parent rock for serpentinite? Select one: a. a sedimentary rock. b. an ultramafic plutonic igneous rock. c. an intermediate plutonic igneous rock. d. a felsic volcanic rock.

b. an ultramafic plutonic igneous rock.

Refer to the sequence of events shown below, which explains the development of an unconformity (gap in the record of geologic time). Which type of unconformity is a surface of erosion that separates overlying sedimentary rock from underlying tilted layers of sedimentary rock? Unconformities: https://www.youtube.com/watch?v=DNcYBLG3TBo Select one: a. disconformity b. angular unconformity Correct c. nonconformity

b. angular unconformity

Evidence suggests the planet Earth formed from __________. Select one: a. volcanism b. asteroid accretion c. a biological experiment in an alien laboratory d. The big bang of a super nova

b. asteroid accretion

All of the following are forces that may contribute to plate movements EXCEPT: Select one: a. convection currents within the asthenosphere. b. centrifugal forces from the rotation of the Earth. c. the gravitational pull of the Earth on the subducting slabs of oceanic lithosphere d. the gravitational pull of the Earth on plates away from the mid-ocean ridges

b. centrifugal forces from the rotation of the Earth.

According to this web page: http://www.nps.gov/prsf/naturescience/chert.htm, chert is best described as a(n): Select one: a. clastic sedimentary rock b. chemical or biologic sedimentary rock Correct c. igneous volcanic rock d. igneous plutonic rock e. metamorphic rock

b. chemical or biologic sedimentary rock Correct

Explore global patterns in topography, which you can play around with to your hearts content using this site: https://www.ldeo.columbia.edu/~small/GDEM.html. Again, you'll want to have your text open to a map of the plate boundaries. The mountain belts highest in elevation tend to be located along which type of plate boundary? Select one: a. divergent boundary (plates moving apart from each other) b. convergent boundary (plates moving toward each other) c. transform boundary (plates sliding past each other) d. There is no association of mountain belts with plate boundary type.

b. convergent boundary (plates moving toward each other)

Examine the map of tectonic plates and earthquakes (see question 1). The west coast of South America, where many earthquakes occur, is which type of plate boundary? Select one: a. divergent boundary b. convergent boundary (subduction type) c. convergent boundary (continental collision type) d. transform boundary

b. convergent boundary (subduction type)

Consider the global volcano distribution in relation to the location of the plate boundaries (there is a nice figure of this in Ch. 2 of your text). Volcanos tend to: Select one: a. occur on plate boundaries b. lie in a chain parallel to plate boundaries c. occur randomly

b. lie in a chain parallel to plate boundaries

Consider the global earthquake distribution in relation to the major plate boundaries. Along transform plate boundaries, earthquakes tend to be: Select one: a. shallow in depth b. shallow to intermediate in depth c. shallow to deep

b. shallow to intermediate in depth

Along what type of plate boundary is new seafloor created? Along what type of plate boundary would you happen to find the oldest seafloor, maybe just before it is destroyed? Examine the map of global topography provided below. Elevation is shown by color, with highest elevations appearing red, and lowest are deep blue. You can see some subtle elevation changes across the oceanic plate, yes? These are shown by a change from aqua to deep blue. What is the most accurate description of water depth related to oceanic crust? Select one: a. water depth is shallowest where seafloor age is oldest. b. water depth is shallowest near the mid-ocean ridges. c. water depth is shallowest where the seafloor is coldest. d. water depth is shallowest in the Pacific Ocean.

b. water depth is shallowest near the mid-ocean ridges.

What would be the most appropriate material for potassium to argon dating? Select one: a. Gypsum beds preserved in a sand from an evaporated lake b. Bone found in a clay bed overlying a 30,000 year old lava flow c. 100 million year old granite in the Sierra Nevada d. Well sorted sediment preserved in cross beds from ancient sand dunes

c. 100 million year old granite in the Sierra Nevada

Based on the estimates of Alfred Wegener, approximately when did the supercontinent called Pangea begin to split apart? Select one: a. 430 million years ago b. 300 million years ago c. 180 million years ago d. 50 million years ago

c. 180 million years ago

Read or check out the video on metamorphic rocks... How does contact metamorphism occur? Select one: a. By hot water circulating through mafic igneous rocks. b. By high pressure (and low-temperature) conditions in subduction zones. c. By heat from the magma of an adjacent igneous intrusion.

c. By heat from the magma of an adjacent igneous intrusion.

Consider the location of Magnitude 8 and greater earthquakes since 1900 based on these resources: http://www.businessinsider.com/map-earthquakes-magnitude-animated-1900-2016-8 and http://www.livescience.com/30320-worlds-biggest-earthquakes-110412.html These are the largest earthquakes in history! There is a pattern in terms of what types of plate boundaries and faults are responsible for these events. You may find it helpful to compare the earthquake locations to the map of major plate boundaries. What type of plate boundary is known to create the most powerful earthquakes? Select one: a. divergent b. transform c. convergent d. transverse e. subvergent

c. convergent

Pressure is a force per area (distance squared.) When someone steps on your foot, you feel the pressure across the top of your foot. But you also feel a bit squashed... right? Imagine if your foot was constrained on all sides... Density is defined as the mass per given volume of a substance. Because pressures at great depths below earth's surface are ___________, earth materials at depth tend to have __________ densities. Read carefully! Select one: a. low, decreased b. low, increased c. high, increased d. high, decreased

c. high, increased

Look back at the definition of a mineral. (See your textbook or the video.) Sugar ___________because______________. Select one: a. is a mineral, it meets all 5 requirements b. is not a mineral, it does not have an orderly internal structure c. is not a mineral, it is organic d. is not a mineral, it is not a solid

c. is not a mineral, it is organic

The sequence of events shown below explains the development of an unconformity (a gap in the record of geologic time). Which type of unconformity is a surface of erosion that separates overlying sedimentary rock from underlying igneous or metamorphic rock? Unconformities: https://www.youtube.com/watch?v=DNcYBLG3TBo Select one: a. disconformity b. angular unconformity c. nonconformity

c. nonconformity

Consider this map which shows the global hotspot (orange dot) distribution in relation to the major plate boundaries (shown as red and black lines #1-3). Hotspots tend to: Select one: a. occur on plate boundaries b. lie in a chain parallel to plate boundaries c. occur randomly

c. occur randomly

Consider how the relative density—and thus the global topography—of two plates affects the outcome, when two plates collide... You may find it helpful to take a look at a few examples, like these! http://www.passmyexams.co.uk/GCSE/physics/convergent-boundaries.html Here, we see convergence between oceanic and continental plates. We also see convergence between 2 continental plates. When oceanic and continental lithosphere meet (or converge), which plate will subduct and why? Select one: a. oceanic because it contains lighter minerals b. continental because it contains lighter minerals c. oceanic because it contains heavier minerals d. continental because it contains heavier minerals

c. oceanic because it contains heavier minerals

Consider the pie charts below, which describe the earth's composition! Which are the two dominant elements found within Earth's crust? Select one: a. oxygen and iron. b. oxygen and aluminum. c. oxygen and silicon. d. iron and silicon.

c. oxygen and silicon.

Consider the global earthquake distribution in relation to the major plate boundaries. Along convergent plate boundaries, earthquakes tend to be: Select one: a. shallow in depth b. shallow to intermediate in depth c. shallow to deep

c. shallow to deep

The asthenosphere is a crystal mush. It is a solid because the pressures below the lithosphere are very high and cause great densities. But the asthenosphere is also very very hot! So... over long periods of time, the asthenosphere behaves like a fluid, and flows!! Because the asthenosphere is _____________, it deforms (changes shape) ________________. Select one: a. solid, elastically (snapping like a rubber band) b. rigid, elastically (snapping like a rubber band) c. solid, plastically (moving like toothpaste that is sheared) d. rigid, plastically (moving like toothpaste that is sheared)

c. solid, plastically (moving like toothpaste that is sheared)

Mineral evidence suggests that on Earth, the oceans first formed as early as _________. Consider the following article, as a cool reference! http://serc.carleton.edu/NAGTWorkshops/earlyearth/questions/formation_oceans.html Select one: a. 4 thousand years ago b. 4 million years ago c. 400 million years ago d. 4.2 billion years ago

d. 4.2 billion years ago

Which of the following best describes an isotope? Select one: a. An atom that has gained or lost electrons and has an electrical charge. b. An atom that has bonded with another atom to form a molecule. c. An atom that has changed into another atom through loss or gain of protons. d. An atom that has more or fewer neutrons than protons

d. An atom that has more or fewer neutrons than protons

Now a question about Geologic Time... Which relative dating principle states that sedimentary layers lower in a sequence are older than the sedimentary layers overlying them? Be sure to read and watch the videos to learn these ideas! Select one: a. Principle of original horizontality b. Principle of cross-cutting relationships c. Principle of inclusions d. Principle of superposition

d. Principle of superposition

Let's review what we know about earth's structure. The earth consists of different zones that can be mapped clearly. We can identify zones based on chemical differences or zones based on other physical characteristics (e.g., solid or liquid). Refer to your textbook's description of the lithosphere (a physical zone). Which of the statements below best describes the lithosphere? Select one: a. The lithosphere is the innermost layer of Earth that consists of metal. b. The lithosphere is the liquid layer of Earth. c. The Earth layer that is mostly solid, but still quite weak. d. The lithosphere is a strong and rigid layer of Earth

d. The lithosphere is a strong and rigid layer of Earth

Read over Appendix A. Which substance is NOT a mineral? Select one: a. Ice b. Quartz c. Mica (biotite) d. Volcanic glass (obsidian)

d. Volcanic glass (obsidian)

The Theory of Plate Tectonics is super powerful, because it explains __________. Select one: a. the global distribution of volcanoes b. the global distribution of earthquakes c. Milankovitch Cycles d. both a and b e. both b and c

d. both a and b

Refer to the map of seafloor age above. Age of the lithosphere is indicated by color, according to the legend on the right. Note that the rocks that make up the continental lithosphere are generally much, much older than the ages shown in this range. Where in the oceans is the newest ocean crust found? Select one: a. in an oceanic trench where it's about to be subducted b. under a continental shelf at a passive margin c. the abyssal plain d. mid-ocean ridges e. all ocean crust is the same age

d. mid-ocean ridges

Again, examine Figure 2.18 and the blue arrows that show relative motion of plates adjacent to plate boundaries! Shear is a force that you feel when you slide into home base, low and slow. Which type of plate boundary is characterized by shear forces? Select one: a. divergent boundary b. convergent boundary (subduction type) c. convergent boundary (continental collision type) d. transform boundary

d. transform boundary

The previous plot of seismic wave velocities was for relatively shallow depths below the earth's surface. Now, consider the attached plot which shows velocities at various depths, including all the way down to the inner core!! Remember that dense, rigid materials (aka solids!) ring like bells, while weaker fluids do not transmit seismic (sound) waves as effectively... You have observed this effect, if you have ever tried yelling out loud under water. The plots above show changes in seismic wave velocity vs. depth, but remember... density is not the only property changing with depth! The state or phase (liquid vs solid) of the different rock layers are also influenced by changes in temperature. Which of the following statements best describes the internal structure of the earth, based on these plots, your reading, and the videos? Select one: a. An orange (a thin peel with a solid, but watery inside) b. A bowling ball (completely solid all the way through) c. An egg (solid at the core, surrounded by liquid and then a hard outer shell) d. A geode (hollow at the center with a strong, hard, outside layer) e. A chocolate covered cherry (solid at the core surrounded by a liquid layer and semi-solid layer, then covered in a thin solid coating)

e. A chocolate covered cherry (solid at the core surrounded by a liquid layer and semi-solid layer, then covered in a thin solid coating)

Based on your reading, it is clear that evidence for plate tectonics comes from: Select one: a. Sonograms of the ocean floor b. Magnetic surveys of the ocean floor c. Volcanic chains that parallel the subduction zones d. Distributions of non-marine fossils across the globe e. All of the above

e. All of the above

Which of the following data listed below provides evidence in support of this accepted age for the planet Earth? Please consider the following article: http://serc.carleton.edu/NAGTWorkshops/earlyearth/questions/formation_oceans.html Select one: a. Radiometric dates of ancient sedimentary zircon b. Radiometric dates of meteorites c. Solar mass and luminosity d. Radiometric dates of Lunar samples e. All of the above

e. All of the above

Again, examine Figure 2.18 and the blue arrows that show relative motion of plates adjacent to plate boundaries! Compression is a force that you feel when someone squeezes your hand too hard. Which type of plate boundary is characterized by compressional stresses? Select one: a. divergent boundary b. convergent boundary (subduction type) c. convergent boundary (continental collision type) d. transform boundary e. B and C

e. B and C

Which of the following statements best describes a volcanic igneous rock? Remember that rocks can consist of bits that aren't minerals... for example: teeth, bones, glass, coal, etc. Select one: a. It cooled slowly, so it is coarse grained (has large-sized crystals). b. It cooled relatively quickly, so it is fine grained (has small-sized crystals). c. It cooled so quickly that no crystals formed (it is a glass). d. A and B e. B and C

e. B and C

What is the age of the Earth determined to be through scientific investigation of evidence? Select one: a. 3.5 million years b. 4.6 million years c. 3.5 billion years d. 4.6 billion years e. 13.5 billion years

4.6 billion years

Half-life is the time that it takes for half of the parent material to decay to the daughter material. The half-life of 40K (K=Potassium) is 1,250 Ma. At that time, half of the potassium has changed into Argon. The graph below shows the relationship between the age of a mineral and a mineral's 40Ar/40K ratio. Again, the daughter product is Argon (Ar) and the parent is Potassium (K). Say you analyze a mineral today and you find that the 40Ar/40K ratio is 1 (meaning the amounts of 40Ar and 40K are equal). Use the graph to determine how many half-lives have occurred. Select one: a. 1 b. 2 c. 3 d. 4

a. 1

Take another peek at your plate tectonic map... What kind of continental margin do we live on here in San Francisco? This describes the familiar San Andreas fault! Select one: a. Active b. Passive c. Marginal d. Atlanticus e. Pacificus

a. Active

The radiolaria that form chert are planktonic critters that live on the surface of the ocean. After dying, they settle slowly through the water column and are deposited on the deep ocean floor. Given this depositional setting, radiolaria likely accumulated on top of which rock? :) Select one: a. Basalt pillows (a type of igneous volcanic rock) Correct b. Granite (an igneous plutonic rock) c. Gneiss (a metamorphic rock) d. Andesite (a type of igneous volcanic rock)

a. Basalt pillows (a type of igneous volcanic rock) Correct

Look back at the plots that show density changing with depth below the earth's surface... Compare and contrast the lithosphere and asthenosphere in terms of composition, temperature, and density. Why do some people think it's correct to say the lithosphere "floats" on the asthenosphere? Select one: a. Because the lithosphere is less dense, it is therefore more buoyant that the asthenosphere. b. Because the asthenosphere is less dense, it is therefore more buoyant that the lithosphere. c. Because the asthenosphere is warmer, it is therefore less buoyant that the lithosphere. d. Because the lithosphere is cooler, it is therefore less buoyant that the asthenosphere

a. Because the lithosphere is less dense, it is therefore more buoyant that the asthenosphere.

Please check out the following USGS web site, which shows the distribution and depths of earthquakes in South America (see your textbook for a map of plate boundaries!): http://maps.unomaha.edu/maher/GEOL1010/lecture15/18q_eqs_pacific_rim_usgs.gif The earthquakes (colored points) coincide really well with the plate boundaries. Often, earthquakes record discrete slip along a fault, so they usually are located nearer to where the fault shows on a map. In this figure, the depth of each earthquake is indicated by the color of the point. Check out the legend on the right of the map, which indicates which colors correspond to which depths. The location of the point on the map is the location of the earthquake epicenter. Once you focus on color, you can see that there are patterns (e.g., rainbows!) In which direction do earthquakes become deeper? In which direction do they occur shallower? Scientists can use this info to deduce the type of fault that is producing the earthquakes, and this info coincides with the type of plate boundary. :) Which statement best describes the depths of earthquakes along the west coast of South America? Select one: a. All earthquakes occur at the same depth. b. Earthquakes are deep at the plate boundary (yellow line at the coast)) and get progressively shallower to the east (on the continent away from the yellow line). c. Earthquakes are shallow at the plate boundary (yellow line at the coast) and get progressively deeper to the east (on the continent away from the yellow line). d. Earthquakes are shallow in the center of the continent and deep along the east and west coasts of the continent.

c. Earthquakes are shallow at the plate boundary (yellow line at the coast) and get progressively deeper to the east (on the continent away from the yellow line).

Refer to the figures in your text (and below) showing 1) the global distribution of tectonic plates and 2) the global distribution of earthquakes. Which of the following statements is true? Select one: a. Earthquakes only happen at tectonic plate boundaries. b. Earthquakes occur at great depths at divergent plate boundaries. c. Earthquakes mostly happen along tectonic plate boundaries

c. Earthquakes mostly happen along tectonic plate boundaries

Read over Chapter 5.1-5.2. Magma cools very slowly where it is insulated beneath Earth's surface. Cooling at this rate produces rock that: Select one: a. Is glassy, like obsidian b. Has very small crystals, like basalt c. Has large crystals, like granite Correct d. Has a mixture of large and small crystals

c. Has large crystals, like granite Correct

Based on your knowledge from the videos and the reading, which of the following is NOT a significant source of the internal heat of the earth? You may also like to study the curve below, which shows how temperature changes with depth below the surface of the earth! (You can find this and other cool plots provided in the folder on iLearn, too). Select one: a. Original heat retained within the planet during formation b. Heat produced during the transformation of liquid magma into a solid inner core c. Heat radiating to the earth from the Sun d. Radioactive decay of elements scattered throughout the mantle and core

c. Heat radiating to the earth from the Sun

Chemical or biologic sedimentary rocks are best described as (for additional info on sedimentary rocks: https://www.youtube.com/watch?v=uozyWZ6XQzM) Select one: a. Made up of broken pieces eroded from other rocks (example: sandstone) b. Formed by the cooling of molten (liquid) rock. c. Made up of pieces of organisms shells (example: limestone) Correct d. Formed deep in the interior of Earth

c. Made up of pieces of organisms shells (example: limestone) Correct

The earth's magnetic field is produced by the movement of charged particles (i.e., electricity!!) In which layer of the earth does this convection of charged particles lead to the earths magnetic field? Select one: a. Crust b. Mantle c. Outer Core d. Inner Core

c. Outer Core

Which of the following statements does not explain why rock at the mid-oceanic ridge is indeed about 2 km higher in elevation than along the adjacent seafloor? This is the average amount of elevation change across the mid-oceanic ridges that you can see in the figure above. Select one: a. This rock is relatively young and hot—therefore less dense. b. The rift features include some volcanic landforms. c. Pillow basalts are only formed at the mid-oceanic ridge.

c. Pillow basalts are only formed at the mid-oceanic ridge.

How has the scientifically accepted age of the Earth been most precisely determined? Select one: a. Relative dating b. Cross-cutting relationships c. Radiometric dating of meteorites d. Stromatolites outgassing e. Genealogy from ancient texts

c. Radiometric dating of meteorites

Based on Chapter 1, which of the following statements is most true. The rock cycle describes: Select one: a. How earth materials are created and destroyed b. The journey of earth materials from the center of the earth to the surface c. The continual recycling of earth's materials at a steady pace Correct d. The recycling of earth's materials with potentially many stops and starts

c. The continual recycling of earth's materials at a steady pace Correct

Given the Principle of Original Horizontality, what event must have occurred following deposition to produce the non-flat-lying stack of rock layers in the picture below? Original Horizontality: https://www.youtube.com/watch?v=mbQ8AIUJ7rg Select one: a. Strike-slip faults slide them around. b. They float to the surface due to low density. c. They are uplifted or exhumed by vertical movement on faults. Correct d. Natural gas pushes them up gradually.

c. They are uplifted or exhumed by vertical movement on faults. Correct

Many metamorphic rocks form deep underground. How is it possible to see these rocks at the surface of the Earth? Select one: a. Strike-slip faults slide them around. b. They float to the surface due to low density. c. They are uplifted or exhumed by vertical movement on faults. Correct d. Natural gas pushes them up gradually.

c. They are uplifted or exhumed by vertical movement on faults. Correct

Examine the geologic cross-section below. The view is "from the side" or along the earth's surface. The cross-section is useful to geologist because it shows the layers, faults, and other cross-cutting features (such as intruding igneous rocks) as if we've sliced open the earth's crust. Take plenty of time to decide which statement is true... Note that feature (F) is a fault. Understanding Geologic Time: Earth's History: https://www.youtube.com/watch?v=Z6k3NRy-YWs Law of superposition: https://www.youtube.com/watch?v=EadTLGMu3LI Original Horizontality: https://www.youtube.com/watch?v=mbQ8AIUJ7rg Geologic Principles: https://www.youtube.com/watch?v=rc3da3-znK4 Unconformities: https://www.youtube.com/watch?v=DNcYBLG3TBo Select one: a. Unit C is younger than Fault F. b. Unit A is younger than Unit C. c. Unit C is younger than Unit B. Correct d. Unit D is younger than Unit C.

c. Unit C is younger than Unit B. Correct