Exam 2: Geology 101, Fall 2001
Name:_______________________________________
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1. Moscow Mountain is mainly composed of (a)_____, while (b)_____ is the rock that occurs in Moscow directly under the soil.
B. (a) basalt, (b) granite
C. (a) garnet, (b) mica
D. (a) shale, (b) basalt
E. none of the above combinations
2. Which sequence of rock types occurs in the Moscow area, from oldest to youngest?
B. granite, basalt, metamorphic belt rocks
C. basalt, metamorphic belt rocks, granite
D. basalt, granite, the shales that contain plant fossils
E. none of the above sequences
3. The metamorphic rocks that occur in our area:
A. are the youngest rocks we saw on the field trip
B. started forming as sediments about 1 billion years ago
C. were converted from sedimentary to metamorphic rocks about 100 to 200 million years ago
E. none of the above
4. The granite that occurs in our area:
A. formed from a magma that crystallized several miles deep about 60 million years ago
B. was formed from magma at a converging plate boundary
C. was exposed at the surface after it was uplifted from several miles deep
E. none of the above
5. The basalt that occurs in our area:
B. was formed when felsic magma erupted at the surface
C. was formed from magma at a converging plate boundary
D. all of the above
E. none of the above
6. About 15 million years ago, deep cracks formed in our area because of a/an (a)_____. The result of these cracks was the formation of (b)_____.
A. (a) converging plate boundary, (b) granite
B. (a) converging plate boundary, (b) basalt
C. (a) diverging plate boundary, (b) granite
D. (a) diverging plate boundary, (b) shale
7. The plant fossils we saw on the field trip were preserved in (a)_____ -sized sediments. These sediments were deposited in a lake which formed behind a/an (b)_____ dam.
A. (a) sand, (b) basalt
B. (a) silt, (b) ice
C. (a) silt, (b) granite
E. none of the above combinations
8. Although we saw no evidence of this on our field trip, another major geological event occurred in our area about 10,000 years ago. It was a major flood that occurred when a lake formed behind a/an _____ dam in Montana emptied in a day or so to produce the Scablands of central Washington.
A. basalt
C. landslide
D. human-made
E. none of the above
9. The current landscape around Moscow and to the west, termed the Palouse, forms as result of:
A. erosion of basalt
C. wind-blown sediments from the east
D. erosion of granite
E. none of the above
10. To summarize the geological development of our region (from past to present): Approximately 1 billion years ago, (a)_____. About 800 million years ago, the area (b)_____. About 100-200 million years ago, (c)_____. The last major rock type, (d)_____, formed about 15 million years ago.
A. (a) metamorphism occurred, (b) was dry, (c) divergence occurred, (d) granite
B. (a) metamorphism occurred, (b) was wet, (c) divergence occurred, (d) basalt
C. (a) sediments were deposited, (b) pulled apart, (c) convergence occurred, (d) basalt
D. (a) sediments were eroded, (b) pulled apart, (c) convergence occurred, (d) granite
E. none of the above combinations
11. The grain size in (a)_____ igneous rocks is smaller than in (b)_____ igneous rocks because the former formed rapidly at the surface of the earth.
A. (a) extrusive, (b) intrusive
B. (a) volcanic, (b) plutonic
C. (a) intrusive, (b) extrusive
E. none of the above combinations
12. (a)_____ magmas are high in Fe and Mg and low in Si, while (b)_____ magmas are low in Fe and Mg and high in Si.
A. (a) Granite, (b) basalt
B. (a) Felsic, (b) mafic
D. (a) Light, (b) dark
E. none of the above combinations
13. Flood basalts form when (a)_____ magma erupts at the surface, and composite volcanoes form when (b)_____.
B. (a) felsic, (b) mafic magmas erupt at the surface
C. (a) intermediate, (b) felsic magmas erupt at the surface
D. (a) mafic, (b) plates pull apart
E. none of the above combinations
14. Volcanoes composed of _____ form when an ocean and continental plate collide.
A. rhyolite
C. basalt
D. granite
E. none of the above
15. _____ is a volcanic rock that forms when lava cools very fast.
A. Rhyolite
B. Andesite
C. Basalt
E. none of the above
16. Magma forms when rocks melt. Rocks can melt (a)_____ and/or (b)_____.
A. (a) when they move deep into the earth, (b) by increases in pressure
C. (a) by increases in temperature, (b) by increases in pressure
D. both A and C
E. none of the above combinations
17. Bowen’s reaction series can be used to explain:
B. why igneous rocks that form on the surface have small grain sizes
C. why igneous rocks that form deep in the earth have large grain sizes
D. all of the above
E. none of the above
18. As a magma starts to cool, (a)_____ is the first formed Fe-Mg rich mineral and (b)_____ is the first formed feldspar.
A. (a) pyroxene, (b) Ca-feldspar
B. (a) olivine, (b) Na-feldspar
D. (a) pyroxene, (b) Na-feldspar
E. none of the above combinations
19. Because different minerals form (i.e., crystallize) at different temperatures, magma compositions will change as these first formed minerals crystallize. In general, this causes:
A. the magma composition to change from mafic to felsic as temperature decreases
B. the magma to become depleted in Fe and Mg
C. the magma to become enriched in Si
E. none of the above
20. Basalt and granite are the most abundant extrusive and intrusive igneous rocks, respectively. The intrusive equivalent of a basalt is (a)_____ and the extrusive equivalent of a granite is (b)_____.
B. (a) diorite, (b) rhyolite
C. (a) andesite, (b) gabbro
D. (a) rhyolite, (b) gabbro
E. none of the above combinations
21. One of the main reasons we care about sedimentary rocks is:
A. they are the most abundant rock in the earth
C. they form from magma
D. they comprise most of the surrounding rocks of our area
E. none of the above
22. I introduced the sediment-sedimentary rock cycle to help us understand how sedimentary rocks form. Which of the following belongs to my sediment-sedimentary rock cycle?
A. weathering
B. erosion and transportation
C. deposition
D. lithification and crystallization
23. (a)____ deals with rocks and minerals breaking apart due to changes in pressure and temperature, while (b)_____ deals with minerals and rocks dissolving.
A. (a) Lithification, (b) crystallization
B. (a) Melting, (b) crystallization
C. (a) Chemical weathering, (b) mechanical weathering
E. none of the
24. One of the end results of chemical weathering is formation of ____.
A. magma
B. metamorphic rock
C. sedimentary rock
E. none of the above
25. Water, wind, ice, and gravity all can erode and transport sediment. Sorting and rounding of sediments give us clues about which of these may have eroded and transported the sediment. For instance, ice would transport sediment of (a)_____ while wind would only carry sediment of (b)____.
A. (a) small size, (b) large size
B. (a) well rounded shapes, (b) poorly rounded shapes
C. (a) many different sizes, (b) large size
E. none of the above combinations
26. Also, the distance sediment is moved can be determined from its rounding. _____ sediment is only transported very short distances.
A. Rounded
C. Well sorted
D. both A and C
E. none of the above
27. Sedimentary structures are used to help determine the depositional environment of a sediment. For instance, (a)_____ would form at the land/water interface and (b)_____ would indicate deposition in a deep lake or the ocean.
A. (a) horizontal-bedding, (b) cross-bedding
B. (a) horizontal-bedding, (b) mud cracks
D. (a) graded-bedding, (b) ripple marks
E. none of the above combinations
28. A recent video of Osama bin Laden showed rocks in the background; based on this, a geologist:
A. predicted that the rocks might contain oil
B. said the rocks could contain gold
C. said the rocks were fake
D. recognized the rocks because of his work on geology in that area and could pinpoint the location
E. none of the above
29. Two of the three major classes of sedimentary rocks are (a)_____ made by lithification of sediments and (b)_____ which form(s) from crystallization of CO3.
A. (a) evaporates, (b) coal
B. (a) sandstone, (b) coal
C. (a) clastic rocks, (b) coal
E. none of the above combinations
30. Sedimentary rocks are classified based on their composition and texture. The texture is partly based on grain size. From smallest to largest, which of the following are the grain sizes used in sedimentary rock classification?
A. silt, clay, sand, gravel
B. mud, silt, clay, sand, gravel
C. gravel, sand, silt, clay
E. none of the above
31. Coal is a sedimentary rock formed from (a)_____ that (b)_____.
B. (a) preexisting sedimentary rocks rich in CO2, (b) were buried deep in the earth
C. (a) animal remains, (b) were exposed on the surface for millions of years
D. (a) wind-blown sediment rich in organic material, (b) did not decay
E. none of the above combinations
32. (a)_____ is a rock composed of very fossils composed of CaCO3, and (b)_____ is a rock composed of very small fossils of SiO2.
A. (a) Limestone, (b) chert
B. (a) Limestone, (b) quartzite
C. (a) Chalk, (b) quartzite
E. none of the above combinations
33. The key criterion for formation of a metamorphic rock is:
A. they form after an increase in temperature has melted a rock
B. they form after a decrease in pressure has melted a rock
C. they form based on changes in temperature and pressure that have melted a rock
D. they form based on changes in temperature and pressure that have not melted a rock
E. none of the above
34. The _____ a metamorphic rock is/are different than what is found in the preexisting rock.
A. minerals occurring in
B. elements present in
C. texture in
E. none of the above
35. If an object undergoes confining pressure, its (a)_____ will change. If an object undergoes normal stress, its (b)_____ will change.
A. (a) shape, (b) shape and size
B. (a) shape and size, (b) size
C. (a) shape, (b) size
E. none of the above combinations
36. There are deviations from the normal geothermal and geopressure gradients. At a diverging plate boundary, there would be a (a)_____ geothermal gradient and a (b)_____ geopressure gradient.
B. (a) lower, (b) higher
C. (a) normal, (b) abnormal
D. (a) abnormal, (b) normal
E. none of the above combinations
37. In the study of metamorphic rocks, phase diagrams are used to:
B. determine when a rock melts
C. determine when a magma crystallizes
D. give the pressure at which the rock breaks
E. none of the above
38. Metamorphic rocks are classified based on their composition, which refers to (a)_____, and texture, which refers to (b)_____.
A. (a) the elements present, (b) grain shape
B. (a) the minerals present, (b) grain size
C. (a) the elements present, (b) grain size
D. (a) whether it is made of one or many minerals, (b) the layering, or lack of, in it
E. none of the above combinations
39. The minerals that occur in a metamorphic rock are:
A. based on the original rock’s composition
B. a function of the pressure and temperature conditions of formation
C. formed after the rocks melts
E. none of the above
40. Foliations in a metamorphic rock are caused by:
B. directed stress in a monomineral rock
C. non-directed stress in a polymineral rock
D. non-directed stress in a monomineral rock
E. none of the above
41. As a shale undergoes increasing P-T and time, it forms which series of rocks?
A. gneiss, phyllite, schist, slate
B. limestone. marble
C. sandstone, quartzite
D. garnet, granite
42. Grain sizes and shapes provide valuable clues as to how a rock forms. For instance, igneous rock tend to have (a)_____ grains, sedimentary rocks have (b)_____ grains, and metamorphic rocks have (c)_____ grains.
A. (a) rounded, (b) flattened, (c) non-interlocking
B. (a) non-interlocking, (b) interlocking, (c) spherical
D. (a) interlocking, (b) non-interlocking, (c) spherical
E. none of the above combinations
43. Geologists use two type of time. (a)____ tells order of events, while (b)_____ put/s numerical ages on events.
A. (a) Relative time, (b) cross-cutting relationships
B. (a) Absolute time, (b) tree rings
C. (a) Absolute time, (b) relative time
D. both B and C
44. From youngest to oldest, which are the three Eras I mentioned in class?
B. Paleozoic, Cenozoic, Mesozoic
C. Paleozoic, Mesozoic, Cenozoic
D. Mesozoic, Paleozoic, Cenozoic
E. none of the above
45. The law of superposition states:
A. sediments are deposited flat
B. sediments are deposited one on top the other, with the youngest on bottom
D. young rocks are always on top of old rocks
E. none of the above
46. The law of cross-cutting relationships states:
B. older material cuts younger material
C. younger material is always on top
D. older material is always on top
E. none of the above
47. Mass wasting can best be defined as:
A. creep
B. landslides
D. both A and B
E. none of the above
48. (a)_____ are examples of factors that control mass wasting, while (b)_____ are examples of triggering mechanisms for mass wasting.
B. (a) Low rainfall and flat ground, (b) oversteepening slopes and ground shaking
C. (a) High relief and steep slopes, (b) stable ground and droughts
D. (a) High humidity and low snowfall, (b) planting trees on slopes and addition of concrete
E. none of the above combinations
49. Mass movements are classified based on the rate of movement, type of material moved, and the nature of movement. The three kinds of movement are (a)_____, where the material behaves as a fluid, (b)_____, where the material moves as a unit, and falling.
A. (a) slip, (b) flow
B. (a) slide, (b) slump
D. (a) water, (b) slide
E. none of the above combinations
50. My ID and name are correctly entered on the scan sheet, and I have answered all the questions on the test and entered them on the scan sheet.
If you don’t know your ID, please ask me.