Download Sedimentary rocks and environments

Physical Geology Learning Objectives and Study Questions
Chapter 7: Tarbuck and Lutgens, 12 ed.
1. Infer a reasonable weathering and transport history for a body of clastic sediment from
observations of its rounding, sorting, and compositional maturity.
2. Recognize planar-, cross-, or graded-bedding in a sedimentary rock sample and use it to
infer the likely conditions of water movement during the sediment's deposition.
3. Many chemical sedimentary rocks—whether of organic or inorganic origin—are made of
silica or calcium carbonate; cite an example of a rock made from each material and describe
how you could distinguish it from one made of the other.
4. Classify common depositional environments as continental, transitional, or marine.
5. Apply the concept of a sedimentary facies to determine whether a sequence of continental
shelf sediments was deposited during marine transgression or regression.
6. Contrast the conditions under which coal, petroleum and natural gas form in terms of their:
geologic settings, source materials, and the physical changes these materials undergo as
fossil fuels develop.
7. Predict the likely locations for petroleum or natural gas traps in a geologic cross-section that
shows the subsurface structure of source, reservoir, and cap rocks.
1. The rock shown in the accompanying photo is best characterized as
a/an _____ sedimentary rock.
A. detrital
B. biogenic
C. chemical
D. inorganic
E. coarse grained
2. The limestone shown in the accompanying photo is best
characterized as a chemical sedimentary rock of _____ origin.
A. evaporite
B. cosmogenic
C. diagenetic
D. biogenic
E. inorganic
3. Of the following transport agents, which is likely to do the best job of producing well-sorted
sediment?
A. debris flow
B. river
C. glacier
D. wind
E. all about the same
4. Typically, the _____ a sediment grain is carried away from its parent rock the more rounded
it becomes.
A. farther
B. faster
C. later
D. more slowly
E. sooner
5. The longer sediment is subjected to weathering and transport the richer in “chemically
stable” minerals, such as _____, it becomes.
A. plagioclase
B. olivine
C. quartz
D. biotite
E. pyroxene
6. Beds such as the one shown at right that change
continuously from coarse bases to fine tops display _____
bedding.
A. cross
B. flannel
C. graded
D. planar
E. reversely graded
7. Continental depositional environments include all of the following, except _____.
A. sand dunes
B. estuaries
C. lakes
D. river floodplains
E. glacial moraines
8. Marine depositional environments include all of the following, except _____.
A. continental shelves
B. carbonate platforms
C. deep seafloor
D. deltas
E. continental slopes
9. The set of characteristics that distinguish one sedimentary rock formation from neighboring
formations deposited at the same time is called _____.
A. sedimentary provenance
B. depositional environment
C. fossil assemblage
D. depositional succession
E. sedimentary facies
10. A coarsening-upward sequence of marine strata records a _____.
A. digression
B. regression
C. intercession
D. recession
E. transgression
11. Oil and natural gas are derived primarily from the
partially-decomposed remains of _____ that have been
entombed in sedimentary strata.
A. dinosaurs
B. marine microorganisms
C. old people
D. plants growing in marshes or swamps
E. trees and forests