Geology 1C Practice Exam 2 (key at bottom)
Professor Bennington

1. Massive outpourings of basaltic lava called flood basalts cover large areas and can be observed:
1. in the dark areas on the surface of the moon
2. in the Watchung Hills of central New Jersey
3. in the Snake River Plateau of Oregon and Idaho
4. all of the above
5. none of the above

2. Metamorphism due to compression during mountain building is called
1. contact metamorphism
2. burial metamorphism
3. regional metamorphism
4. cataclastic metamorphism
5. fluid metamorphism

3. Magma is composed of which of the following components:
1. molten rock
2. gas
3. some solid crystals of mineral
4. all of the above
5. 1 and 2 only

4. Extrusive and volcanic igneous rocks are usually
1. aphanitic
2. phaneritic
3. pegmatitic
4. mafic
5. felsic

5. The source of most of the calcium carbonate sediments that form limestones is...
1. inorganic precipitation in seawater
2. mechanical weathering of pre-existing limestones
3. chemical weathering of sandstones
4. precipitation by marine organisms
5. all of the above

6. Placer deposits are important because they are...
1. mineral buildups that damage your teeth
2. important indicators of volcanic activity
3. a major source of oil
4. a major source of coal
5. concentrations of gold and other heavy minerals

7. Which of the following is a low grade metamorphic rock produced from shale?
1. slate
2. gneiss
3. marble
4. amphibolite
5. schist

8. Which of the following is a foliated metamorphic rock?
1. gneiss
2. quartzite
3. marble
4. hornfels
5. all of the above

9. Bauxite, an important ore of aluminum, is produced by this process:
1. crystallization of igneous magma
2. concentration by streams and rivers in placer deposits
3. intense weathering of feldspar-rich, tropical soils
4. upward migration of aluminum ions in rock strata
5. hydrothermal leaching around volcanic vents

10. As the percentage of silica increases in a magma, its viscosity:
1. decreases
2. increases
3. remains the same

11. Which of the following is NOT an important economic use of sedimentary rock?
1. crushed stone for highways
2. raw material for concrete
3. raw material for glass
4. source rock for oil and natural gas
5. source rock for diamonds

12. A typical example of a shield volcano is
1. Mt. Saint Helens
2. Mt. Fuji
3. Mt. Rainier
4. Mona Loa
5. Vesuvius

13. Sedimentary rocks composed of fragments of shell and mineral from marine organisms are called:
1. carbonates
2. clastics
3. evaporites
4. limestones
5. both 1 and 4

14. A by-product of the chemical reaction of acid with limestone is...
1. carbon dioxide gas bubbles
2. oxygen gas bubbles
3. nitrogen gas bubbles
4. sulphur
5. ammonia

15. Magmas that erupt explosively (such as in Mt. Saint Helens) contain this combination of attributes:
1. low viscosity and low gas content
2. low viscosity and high gas content
3. low viscosity and no gas
4. high viscosity and high gas content
5. high viscosity and low gas content

16. Mature sediments are:
1. poorly sorted and angular
2. poorly sorted and rounded
3. well sorted and angular
4. well sorted and rounded
5. none of the above

17. Weathering does which of the following?
1. breaks down rock into sediments
2. forms soils
3. forms some economic mineral deposits
4. all of the above
5. 1 and 2 only

18. During metamorphism, limestone is transformed into this rock:
1. quartzite
2. schist
3. gneiss
4. slate
5. marble

19. The spontaneous tendency for rock to fracture as pressure is released from it at the surface is called:
1. spalling
2. wedging
3. cleaving
4. fracturing
5. jointing

20. Which is an important characteristic of sedimentary rocks?
1. they are layered
2. they form at the surface of the Earth
3. they contain fossils
4. they contain information about past environments
5. all of the above

21. Obsidian is different from most volcanic rocks in that it
1. contains no minerals
2. is green in color
3. is erupted underground
4. is erupted underwater
5. is radioactive

22. Sedimentary rocks composed primarily of eroded fragments of mineral are called:
1. clastic
2. carbonate
3. chemical
4. evaporite
5. organic

23. Which of the following is caused by differential pressure during metamorphism:
1. foliation
2. schistocity
3. cleavage
4. all of the above
5. 2 and 3 only

24. When hot spots or rifting beneath continents melts continental crust, this type of magma forms:
1. basaltic
2. andesitic
3. rhyolitic

25. Which of the following are common minerals in evaporite deposits?
1. halite and gypsum
2. calcite and dolomite
3. quartz and clay
4. pyroxene and amphibole
5. biotite and muscovite

26. The viscosity of a lava is determined primarily by
1. silica content
2. temperature
3. water content
4. age of the volcano
5. both 1 and 2

27. Light colored igneous rocks contain large amounts of these minerals:
1. pyroxene and amphibole
2. olivine and pyroxene
3. quartz and pyroxene
4. quartz and feldspar
5. mica and pyroxene

28. This type of volcano is associated with subduction zones and island arcs where oceanic crust is remelted:
1. shield volcano
2. composite or stratovolcano
3. cinder cone volcano
4. both 1 and 3
5. volcanoes do not occur in these regions

29. Igneous rocks can be observed in the process of formation:
1. when volcanoes erupt
2. during earthquakes
3. in deep mines
4. igneous rocks can never be observed in the process of formation
5. on the moon

30. The sequence of steps in the formation of a sedimentary rock are:
1. sediment production, transport, deposition, burial, compaction, cementation
2. sediment production, transport, burial, deposition, compaction, cementation
3. transport, deposition, burial, compaction, cementation, sediment production
4. sediment production, deposition, transport, burial, compaction, cementation
5. sediment production, transport, deposition, cementation, compaction, burial

31. Basaltic magmas are low in silica and produce this type of volcano:
1. shield volcano
2. stratovolcano
3. cinder cone volcano

32. Andesitic volcanic eruptions are the most destructive because they:
1. occur explosively
2. project huge clouds of hot gas and rock fragments
3. eject extremely large volumes of liquid lava
4. are unpredictable
5. both 1 and 2

33. Pillow structures result when lava is erupted
1. underground
2. underwater
3. in the air
4. into cold air
5. into hot air

34. Which of the following is NOT a foliated metamorphic rock?
1. schist
2. gneiss
3. phyllite
4. slate
5. marble

35. The difference between magma and lava is:
1. magma is cooler than lava
2. magma is darker than lava
3. magma is not molten
4. magma becomes lava when it erupts on the surface
5. lava has more gas in it than magma

36. Which of the following are important effects of metamorphism?
1. regrowth of crystals
2. reorientation of mineral grains
3. recrystallization of new minerals
4. all of the above
5. 1 and 2 only

37. Which of the following is a high grade metamorphic rock produced from shale?
1. gneiss
2. slate
3. marble
4. quartzite
5. phyllite

38. Enlargement of fractures in rock occurs because of:
1. ice wedging
2. crystal wedging
3. plant root wedging
4. all of the above
5. none of the above

39. Mature sediments have which of the following characteristics?
1. they are well rounded and poorly sorted
2. they are well rounded and well sorted
3. they are angular and poorly sorted
4. they contain an abundance of minerals
5. they are rich in mica and feldspar

40. Metamorphism due to baking of rock by igneous intrusions is called:
1. contact metamorphism
2. burial metamorphism
3. regional metamorphism
4. cataclastic metamorphism
5. fluid metamorphism

41. Explosive volcanic eruptions are caused by
1. high quantities of gas in the magma
2. high viscosity magma
3. excess heat in the magma
4. both 1 and 2
5. 2 and 3 only

42. Which of the following is NOT true about sedimentary rocks
1. they form only at the surface of the Earth
2. they form deep in the Earth's interior
3. they are usually layered
4. they are composed mostly of quartz, clay, or calcite
5. they are granular in texture

43. The main difference between chemical and mechanical weathering is...
1. mechanical weathering does not destroy existing minerals but chemical weathering does
2. chemical weathering is slower than mechanical weathering
3. chemical weathering only occurs in dry climates
4. mechanical weathering destroys minerals but chemical weathering does not
5. chemical weathering only affects carbonate rock

44. Rainwater contributes to chemical weathering because...
1. it is usually warm
2. it contains abundant metallic ions
3. it is usually mildly salty
4. it is always mildly basic
5. it is always mildly acidic

45. Sedimentary deposits of the minerals halite and gypsum crystallized out of sea water are called:
1. carbonates
2. clastics
3. conglomerates
4. evaporites
5. sandstones

46. The main types of gas in magma are:
1. water vapor and carbon dioxide
2. hydrogen sulfide and ammonia
3. carbon dioxide and ammonia
4. carbon monoxide and methane
5. water vapor and methane

47. Iron minerals chemically weathering into a rusty red residue is an example of 1. acid attack
2. oxidation
3. hydrolysis
4. dehydration sythesis
5. reduction

48. The most common mineral products of chemical weathering are:
1. quartz and feldspar
2. quartz and clay
3. clay and mica
4. calcite and dolomite
5. silicon and oxygen

49. Prograde metamorphism occurs at a much faster rate than retrograde metamorphism due to...
1. the presence of organic matter in surface rocks
2. the presence of water in surface rocks
3. the presence of oxygen in surface rocks
4. the absence of water in surface rocks
5. the absence of oxygen in surface rocks

50. Measured from its base, the largest volcano on the Earth is where?
1. in the Andes
2. in Japan
3. in Washington State
4. in Hawaii
5. in Mexico

Answer Key
1. 4
2. 3
3. 4
4. 1
5. 4
6. 5
7. 1
8. 1
9. 3
10. 2
11. 5
12. 4
13. 5
14. 1
15. 4
16. 4
17. 4
18. 5
19. 5
20. 5
21. 1
22. 1
23. 4
24. 3
25. 1
26. 5
27. 4
28. 2
29. 1
30. 1
31. 1
32. 5
33. 2
34. 5
35. 4
36. 4
37. 1
38. 4
39. 2
40 .1
41. 4
42. 2
43. 1
44. 5
45 .4
46 .1
47. 2
48. 2
49 .2
50 .4