Geology Chapter 6

14.___ is a sedimentary rock formed by the cementation of coarse angular fragments of rubble. A. Breccia B. Conglomerate C. Boulder rock D. Arkose E. Cataclastic

A

22._______ sediments are deposited or precipitated as a result of the actions of organisms. A. Biochemical B. Pyroclastic C. Hyaloclastic D. Siliciclastic E. Calciclastic

A

6. ____ is the process by which sediment grains are selected and separated according to grain size by agent of transportation. A. Sorting B.Grading C.Distillating D.Selection E.Segregation

A

11. The most common type of sedimentary rocks are ____. A. inorganic B. detrital C.chemical D.biochemical E.carbonates

B

12.A sedimentary rock that consists of sediment grains bound by cement into a rigid framework is called _______. A. crystalline B. clastic C. biochemical D. organic E. recycled

B

20. Carbonate rocks contain the _____ ion as part of their chemical composition. A. CaO32- B. CO32- C. CaCO32- D. limestone E. Carbonate rocks do not contain ions

B

24. _____ are precipitated as a result of inorganic processes. A. Chalks B. Oolitic limestones C.Coals D.Calcic sandstones E.Fossiliferous limestones

B

29.The principle of ___ holds that, in a stack of horizontal layers the oldest layer is on the bottom and the layers become younger upward. A.supposition B.superposition C.superannualation D.original horizontality E.bedding

B

31.___ are features found within sedimentary rock that formed during or shortly after deposition. A. Bedding planes B. Sedimentary structures C. Laminations D. Formations E. Turbidity currents

B

10.The most common cements are _____ and ____. A.hematite; limonite B.dolomite; halite C.calcite; quartz D.olivine; pyroxene E.feldspar; mica

C

15.______ are sedimentary rocks deposited by direct precipitation of minerals from water. A. Hydro rocks B. Clastic rocks C. Chemical rocks D. Aquatic rocks E. Biologic rocks

C

17. A(n) ______ is sandstone in which more than 15% of the rock's volume consists of fine- grained matrix. A.quartz sandstone B.quartzite C. graywacke D.oolitic limestone E.arkose

C

19._____ form(s) only in fine-grained sediments that are exposed to air. A.Cross beds B.Cleavage C.Mudcracks D.Bedding E.Ripples

C

23._______ limestones are precipitated through the actions of organisms. A.Hyaloclastic B.Calciclastic C.Bioclastic D.Siliciclastic E.Pyroclastic

C

26.___ is a hard, compact, very fine-grained sedimentary rock composed entirely of silica. A. Tuff B. Chalk C. Chert D. Travertine E. Claystone

C

3.Silt is mostly composed of ___ grains. A.clay mineral B.feldspar C. quartz D.mica E.calcite

C

30.Oil and natural gas originate from _____ in marine sediments. A. peat B. the earth's interior C. organic matter D. coal E. comet impacts

C

33.Asymmetrical _____ are produced by current flowing in a single direction. A. wave marks B. ridge marks C. ripple marks D. mullion marks E. burrow marks

C

35.Sedimentary rock on ____ will enable planetary geologists to one day unravel its history. A. the moon B. Jupiter C. Mars D. Mercury E. Io

C

38.A(n) ____ is a body of sediment deposited when a river flows into standing water, like a lake or sea. A. formation B. alluvial fan C. delta D. sandbar E. intrusive deposit

C

13._______ is an organic rock formed from the compression and alteration of plant remains such as leaves, twigs, and tree trunks. A. Crystalline B. Clastic C. Bioclastics D. Coal E. Recycled

D

18.A _____ is a layer of sedimentary rock with a vertical change in particle size, usually from coarse at the bottom to fine at the top. A. patterned bed B. cross bed C. sorted bed D. graded bed E. schist

D

21.The two primary types of carbonate sedimentary rocks are ___ and dolostone. A. dolomite B. gypsum C. coal D. limestone E. sandstone

D

27.Rock salt is composed of the mineral ______. A.calcite B.trona C.dolomite D.halite E.gypsum

D

32.___ are polygonal patterns that form in very fine sediment as it dries. A.Ripple marks B.Cross beds C.Burrows D. Mud cracks E. Graded beds

D

34.In sandstone, a thick bed will often consist of a series of thinner inclined beds called____. A. laminations B. ripple beds C. graded beds D. cross beds E. tweed beds

D

36.Continental environments include all of the following except __. A. lake beds B. river beds C. glacial deposits D. coral reefs E. alluvial fans

D

37.A(n) ___ is a body of rock of considerable thickness that is large enough to be mappable and with characteristics that distinguish it from adjacent rocks. A. layer B. bed C. blanket D. formation E. epoch

D

39._____ are massive deposits of limestone. A.Turbidity flows B.Alluvial fans C.Deltas D. Reefs E. Lithosomes

D

4.Sand grains can be distinguished from silt grain by ____. A. the gritty feel between the teeth B. seeing the individual sand grains C. composition of the grains D. the gritty feel between the fingers. E. only by a microscope

D

5.Under what conditions is a sediment considered to be well-sorted? A. when the grains contains a wide variety of grain sizes mixed together B. when the grains contains just one general grain size and one mineral C. when the grains are in individual layers D. when the grains are nearly all the same size E. when the grains contain just one or two general grain sizes

D

8.______ is the shift to a tighter packing of sediment grains due to the weight of overburden. A. Cementation B. Recrystallization C. Preservation D. Compaction E. Deposition

D

9.______ is the general term for the processes that convert loose sediment into sedimentary rock. A. Gluing B. Hardening C. Crystallization D. Lithification E. Stiffening

D

1.In order of decreasing size (largest listed first), sedimentary grain sizes include __. A. clay, sand, silt, and gravel B. gravel, sand, clay, and silt C. sand, gravel, silt, and clay D. gravel, sand, silt, and clay E. gravel, silt, sand, and clay

D. gravel, sand, silt, and clay

16.A(n) ___ is sandstone containing a significant amount of feldspar. A.marble B.quartz sandstone C.graywacke D.shale E. arkose

E

2._____ is a coarse-grained sedimentary rock formed by the cementation of rounded gravel. A. Breccia B. Mega sandstone C. Pebble rock D. Boulder rock E. Conglomerate

E

25.____ limestones have a clastic texture. A.Fossiliferous B.Bioclastic C.Inorganic D.Chemical E.Oolitic

E

28. Peat is a brown lightweight unconsolidated deposit that ultimately can transform into____. A.bogolite B.swampstone C.crude oil D.shale E.coal

E

40. ______ forms from limestone when the calcium in calcite is partially replaced by magnesium. A.Gypsum B.Halite C.Chert D.Quartz E.Dolomite

E

7._____ is a term that describes a series of visible layers in sedimentary rock. A.Units B.Tables C.Sheets D.Planes E.Bedding

E