Chapter 7 Sedimentary Rocks

Front 1

bedding plane, p 236

Back 1

a nearly flat surface separating two beds of sedimentary rock. Each bedding plane marks the end of one cycle of deposition and the beginning of another cycle with different characteristics.

Front 2

beds, p 236

Back 2

see "strata"

Front 3

biochemical, p 220

Back 3

a type of chemical sediment forming when material dissolved in water is precipitated by water-dwelling organisms. Shells are common examples.

Front 4

cementation, p 213

Back 4

one of the ways that sedimentary rocks are lithified. Material precipitating from water percolating through the sediment fills up open spaces and glues the sediment pieces into a solid mass.

Front 5

chemical sedimentary rock, p 214

Back 5

sedimentary rock made up of material precipitated from water because of inorganic or organic processes

Front 6

clastic texture, p 228

Back 6

A sedimentary rock texture consisting of broken fragments of preexisiting rock.

Front 7

compaction, p 213

Back 7

a type of lithification where the weight of overlying material compresses underlying buried sediments. Compaction is most easily recognized in fine-grained sedimentary rocks such as shale.

Front 8

cross-bedding, p 235

Back 8

a principle of relative dating or rock units. A rock or fault is younger than any rock or fault through which it cuts. The older unit had to be there first in order to be changed (intruded into, faulted).

Front 9

crystalline texture, p 228

Back 9

same as "nonclastic texture"

Front 10

detridal sedimentary rock, p 214

Back 10

rocks forming from accumulated materials originating and transported as solid particles. The particles can come from mechanical weathering, or chemical weathering, or both.

Front 11

diagenesis, p 212

Back 11

the general term for changes taking place after sediments are deposited. These changes can be chemical, physical, or biological in origin. The changes can take place during lithification, or after lithification, or both.

Front 12

environment of deposition, p 228

Back 12

a geographic setting where sediment accumulates. Each site offers a unique combination of geologic processes and environmental conditons.

Front 13

evaporite deposit, p 223

Back 13

a deposit of chemical sedimentary rock formed as material is deposited from solution by the evaporation of water.

Front 14

facies, p 235

Back 14

a section of a rock unit that has a unique set of characteristics distinguishing it from other parts of the same unit

Front 15

fissibility, p 216

Back 15

the property of splitting easily into layers along closely spaced, parallel surfaces, such as bedding planes in shale.

Front 16

fossil, p 23

Back 16

the remains or traces of organisms preserved from the geologic past

Front 17

graded bed, p 237

Back 17

a layer of sediment that has larger particles on the top and smaller particles on the bottom. Graded beds change gradually in grain size from top to bottom.

Front 18

lithification, p 213

Back 18

The process, generally cementation, or compaction (or both) converting sediments to solid rock.

Front 19

mud crack, p 238

Back 19

a feature in some sedimentary rocks that forms when wet mud dries out, shrinks, and cracks

Front 20

nonclastic texture, p 228

Back 20

a term for the texture of sedimentary rocks in which the minerals form a pattern of interlocking crystals.

Front 21

ripple mark, p 237

Back 21

small waves of sand that develop on the surface of a sediment layer by the action of moving air or water.

Front 22

salt flat, p 224

Back 22

a white crust on the ground produced when water evaporates and leaves its dissolved materials behind.

Front 23

sediment, p 212

Back 23

unconsolidated particles created by the weatering and erosion of rock, by chemical precipitation from solution in water, or from the secretions of organisms. Sediments are transported by water, wind, or glaciers.

Front 24

sedimentary environment, p 228

Back 24

same as "environment of deposition"

Front 25

sorting, p 216

Back 25

the degree of similarity in particle size in sediment or sedimentary rock

Front 26

strata, p 236

Back 26

parallel layers of sedimentary rock

Front 27

Shale

Back 27

fissile sedimentary rock composed of layers of claylike, fine-grained sediments

Front 28

Sandstone

Back 28

sedimentary rock consisting of sand held together by cement such as quartz or calcite

Front 29

conglomerate

Back 29

composite sedimentary rock made up of rounded particles of varying size

Front 30

sedimentary breccia

Back 30

a sedimentary rock consisting of sharp angular fragments embedded in clay or sand

Front 31

precipitation

Back 31

process of forming a chemical precipitate

Front 32

organic

Back 32

carbon-based compound

Front 33

inorganic

Back 33

compound not containing carbon

Front 34

Coquina

Back 34

soft porous limestone, composed essentially of fragments of shells and coral,

Front 35

chalk

Back 35

soft compact calcite, CaCO3, with varying amounts of silica, quartz, feldspar, or other mineral impurities, generally gray-white or yellow-white and derived chiefly from fossil seashells

Front 36

limestone

Back 36

common sedimentary rock consisting mostly of calcium carbonate (calcite), CaCO3, used as a building stone and in the manufacture of lime, carbon dioxide, and cement.

Front 37

dolostone

Back 37

carbonate rock made up predominately of the mineral dolomite, CaMg(C03)2

Front 38

chert

Back 38

variety of silica containing microcrystalline quartz siliceous rock occurring as inclusions within limestone.

Front 39

evaporite

Back 39

sedimentary deposit resulting from the evaporation of seawater

Front 40

coal

Back 40

carbonized vegetable matter deposited in the Carboniferous period

Front 41

jasper

Back 41

opaque form of quartz; red or yellow or brown or dark green in color; used for ornamentation or as a gemstone

Front 42

agate

Back 42

an impure form of milky or gray quartz used as a gemstone and for making mortars and pestles

Front 43

flint

Back 43

very hard, fine-grained, opaque quartz that sparks when struck with steel

Front 44

Peat

Back 44

partially carbonized vegetable matter saturated with water; can be used as a fuel when dried

Front 45

Lignite

Back 45

intermediate soft, brownish-black coal in which the alteration of vegetable matter has proceeded further than in peat but not as far as in bituminous coal. Also called brown coal.

Front 46

bituminous coal

Back 46

rich in tarry hydrocarbons; burns readily with a smoky yellow flame

Front 47

anthracite coal

Back 47

hard natural coal that burns slowly and gives intense heat

Front 48

facies

Back 48

rock or stratified body distinguished from others by its appearance or composition.

Front 49

coprolite

Back 49

fossilized excrement