Chapter 6 Vocabulary Flashcards Preview

Geology 4 Test 2 > Chapter 6 Vocabulary > Flashcards

Flashcards in Chapter 6 Vocabulary Deck (48):
1

sediment

Loose, solid particles that can originate by
1. weathering and erosion of preexisting rocks,
2. chemical precipitation from solution, usually in water, and
3. secretion by organisms

2

gravel

Rounded particles coarser than 2 millimeters in diameter

3

sand

Sediment composed of particles with a diameter between 1/16 and 2 millimeters

4

clay

Sediment composed of particles with diameter less than 1/256 millimeter

5

transportation

The movement of eroded particles by agents such as rivers, waves, glaciers, or wind

6

rounding

The grinding away of sharp edges and corners of rock fragments during transportation

7

sorting

Process of selection and separation of sediment grains according to their grain size (or grain shape or specific gravity)

8

deposition

The settling or coming to rest of transported material

9

environment of deposition

The location in which deposition occurs, usually marked by characteristic physical, chemical, or biological conditions

10

lithification

The consolidation of sediment into sedimentary rock

11

pore space

The total amount of space taken up by opening between sediment grains

12

compaction

A loss in overall volume and pore space of a rock as the particles are packed closer together by the weight of overlying material

13

cement

The solid material that precipitates in the pore space of sediments, binding the grains together to form solid rock

14

cementation

The chemical precipitation of material in the spaces between sediment grains, binding the grains together into a hard rock

15

clastic texture

An arrangement of rock fragments bound into a rigid network by cement

16

crystallization

Crystal development and growth

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crystalline texture

An arrangement of interlocking crystals

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sedimentary rock

Rock that has formed from
1. lithification of any type of sediment,
2. precipitation from solution, or
3. consolidation of the remains of plants or animals

19

detrital sedimentary rock

A sedimentary rock composed of fragments of preexisting rock

20

chemical sedimentary rock

A rock composed of material precipitated directly from solution

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organic sedimentary rock

Rock composed mostly of the remains of plants and animals

22

sedimentary breccia

A course-grained sedimentary rock (grains courser than 2 millimeters) formed by the cementation of angular rubble

23

conglomerate

A coarse-grained sedimentary rock (grains coarser than 2 millimeters) formed by the cementation of rounded gravel

24

sandstone

A medium-grained sedimentary rock (grains between 1/16 and 2 millimeters) formed by the cementation of sand grains

25

alluvial fan

Large, fan-shaped pile of sediment that usually forms where a stream's velocity decreases as it emerges from a narrow canyon onto a flat plain at the foot of a mountain range

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matrix

Fine-grained material found in the pore space between larger sediment grains

27

shale

A fine-grained sedimentary rock (grains finer than 1/16 millimeter in diameter) formed by the cementation of silt and clay (mud).
Has thin layers (lamentations) and an ability to split (fissility) into small chips

28

limestone

A sedimentary rock composed mostly of calcite

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recrystallization

The development of new crystals in a rock, often of the same composition as the original grains

30

dolomite

A sedimentary rock composed mostly of the mineral dolomite

31

chert

A hard, compact, fine-grained sedimentary rock formed almost entirely of silica

32

evaporite

Rock that forms from crystals precipitating during evaporation of water

33

coal

A sedimentary rock formed from the consolidation of plant material. It is rich in carbon, usually black, and burns readily

34

sedimentary structure

A feature found within sedimentary rocks, usually formed during or shortly after deposition of the sediment and before lithification

35

bedding

An arrangement of layers or beds of rock

36

original horizontality

The deposition of most water-laid sediment in horizontal or near-horizontal layers that are essentially parallel to Earth's surface

37

bedding plane

A nearly flat surface separating two beds of sedimentary rock

38

cross-bedding

An arrangement of relatively thin layers of rock inclined at an angle to the more nearly horizontal bedding planes of the larger rock unit

39

ripple mark

Any of the small ridges formed on sediment surfaces exposed to moving wind or water. The ridges form perpendicularly to the motion

40

graded bed

A single bed with coarse grains at the bottom of the bed and progressively finer grains toward the top of the bed

41

turbidity current

A flowing mass of sediment-laden water that is heavier than clear water and therefore flows downslope along the bottom of the sea or a lake

42

mud crack

Polygonal crack formed in very fine-grained sediment as it dries

43

fossil

Traces of plants and animals preserved in rock

44

formation

A body of rock of considerable thickness that has a recognizable unity or similarity making it distinguishable from adjacent rock units.
Usually composed of one bed or several beds of sedimentary rock, although the term is also applied to units of metamorphic and igneous rock.

45

contact

Boundary surface between two different rock types or ages of rocks

46

source area

The locality that eroded to provide sediment to form a sedimentary rock

47

silt

Sediment composed of particles with a diameter of 1/256 to 1/16 millimeter

48

porosity

The percentage of rock's volume that is taken up by openings