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.
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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
How does burial of sediment promote diagenesis as sediment converts to rock?
A. Burial subjects the sediment to increased fluids not available at the surface of the Earth.
Burial subjects the sediment to increasingly higher temperatures and pressures.
C. Burial causes sediment to partially melt and dissolve.
D. Burial causes a sediment pile to increase spaces between grains, allowing more water to flow through it.
Which of these sedimentary rocks would most likely form in the deepest water?
A. breccia
B. sandstone
C. limestone
D. conglomerate
Desert floods arrive suddenly and subside quickly.
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