Why do metamorphic changes occur at great depths?
A. Greater depths are the locations of greater temperature and pressure necessary for metamorphism.
B. Temperature increases with depth, causing rocks descending deeper to become progressively less stable and to metamorphose in response.
C. Great depth is the area where most chemically active fluids are found, thus producing the most amount of hydrothermal metamorphism.
D. Temperature decreases with depth, causing rocks descending deeper to become progressively less stable and to metamorphose in response.
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Which of these is the most complete list of the agents of metamorphism, the agents that drive metamorphic transformations in rocks?
A. pressure, temperature, heat
B. chemically active fluids, pressure, differential stress
C. heat, differential stress, chemically active fluids
D. heat, pressure, parent rock
The three most common sedimentary environments are：
A. fluvial, aeolian, marine
B. continental, marine, abyssal
C. continental, marine, transitional
D. continental, alpine, oceanic
As we discussed in the class, shale is a common rock in the sedimentary rock world, but why isn't it as prominently exposed at the surface as sandstone?
A. Shale crumbles easily, causing increased mechanical weathering, whereas sandstone resists weathering more effectively.
B. Shale dissolves in water, whereas sandstone dissolves only if enough carbonic acid is present in the water.
C. Shale resists weathering more effectively, whereas sandstone crumbles easily, causing increased mechanical weathering.
D. Shale has easily broken, highly reactive minerals, whereas sandstone has harder-to-break minerals.
Which of the following statements appropriately describe the characteristics of quartz sandstone?
A. well-sorted, medium-size (up to 2 mm) particles, large pore spaces, accounts for about 20% of sedimentary rocks
B. silt- and clay-size particles, small pore spaces, accounts for > 50% of sedimentary rocks
C. quartz, feldspar and rock fragments dominate, poorly sorted, angular grains
D. angular large particles that are poorly sorted, few pore spaces
E. gravel- and sometimes boulder-sized particles that are poorly sorted and rounded, few pore spaces
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