sedpet review

Question 1

2 types of weathering

Answer 1

mechanical and chemical

Question 2

physical destruction of the original rock

Answer 2

mechanical weathering

Question 3

decomposes minerals in the rocks

Answer 3

chemical weathering

Question 4

Loose deposits are converted into rocks by the processes of ____ and ____, which include ____ and ____ of the loose materials

Answer 4

diagenesis and lithification

compaction and cementation

Question 5

2 products of mechanical weathering

Answer 5

detritus/clastic material
terrigenous sediments

Question 6

solid fragments and mineral particles from mechanical weathering

Answer 6

detritus or clastic material

Question 7

sediments with clastic textures

Answer 7

terrigenous sediments

Question 8

2 sediment products from chemical weathering

Answer 8

orthochemical sediments and allochemical sediments

Question 9

truly chemical sediments which are products of chemical decomposition

Answer 9

orthochemical sediments

Question 10

organisms have caused the precipitation of the major sedimentary mineral components, or the precipitated minerals have undergone substantial movement (and redeposition) after their crystallization, different

Answer 10

allochemical sediments

Question 11

what two points are important for sediments to be classified as allochemical?

Answer 11

• organisms caused the precipitation
• or precipitated minerals have repositioned after crystallization

Question 12

describe the flow of source rock to sedimentary rocks

Answer 12

source rock
> (mechanical and chemical weathering) detritus > (transportation) clastic sediment > (burial and lithification) terrigenous sedimentary rock

> (chemical weathering) solution > (transportation and precipitation) chemical precipitate

breaks into
> (diagenesis and lithification) orthochemical sedimentary rock
or
> (cementation, fragmentation and transport with basin) allochemical sedimentary rock with clastic texture

Question 13

what are the three major categories of sedimentary rocks

Answer 13

I. terrigenous sedimentary rocks (clastic texture)
II. allochemical sedimentary rocks (biochemical/biogenic, with clastic texture)
III. orthochemical sedimentary rocks

Question 14

type of sedimentary rock that includes conglomerates, breccias, sandstones, mudstones, agglomerates and volcaniclastic sandstones

Answer 14

terrigenous sedimentary rocks

Question 15

type of sedimentary rock that includes limestone, dolostones, phosphorites, chert and coal

Answer 15

allochemical sedimentary rocks

Question 16

type of sedimentary rock that includes cherts, travertine and iron formations

Answer 16

orthochemical sedimentary rocks

Question 17

consist of detrital grains, which form the framework of the rock, and which are joined together by cement

Answer 17

Terrigenous sedimentary rocks

Question 18

T or F: Variable amounts of matrix, which consists of fragmental material substantially smaller than the mean size of the framework grains, may also be present in terrigenous sedimentary rocks

Answer 18

T

Question 19

The texture is a composite of the ___, ____, ____ and ____ of the framework grains.

Answer 19

grain size, grain shapes, sorting, and angularity

Question 20

draw the udden wentworth and krumbein scales

Answer 20

refer to notes

Question 21

conversion formula from mm to phi

Answer 21

phi = -log2 d

Question 22

consists of large clasts (boulders, cobbles, pebbles, and granules) with or without a sandy matrix;

Answer 22

conglomerates and breccias

Question 23

show pronounced rounding of the clasts

Answer 23

conglomerates

Question 24

contain more angular clasts

Answer 24

breccias

Question 25

coarse-grained pyroclastics (volcanic debris) with a grain size over 32 mm

Answer 25

agglomerates or volcanic breccias

Question 26

finer-grained (grain size between 2 and 0.062 mm) and most easily classified by determining the amounts of clastic (framework) grains composed of quartz (and chert), feldspar, and lithic fragments

Answer 26

sandstone

Question 27

when the sandstone matrix constitutes more than 10 volume percent of the rock

Answer 27

wacke

Question 28

mostly dark gray sandstones with abundant matrix

Answer 28

greywacke

Question 29

sandstones made up of chiefly volcanic fragments, volcanic glass, and crystals.

Answer 29

volcaniclastics

Question 30

why do volcaniclastics tend to be green

Answer 30

bc of chlorite

Question 31

draw the sandstone classification diagram

Answer 31

refer to notes

Question 32

general term for sediments composed mainly of silt-sized, (0.062 to 0.004 mm) and clay-sized (<0.004 mm) particles

Answer 32

mudstone

Question 33

silt particle size

Answer 33

siltstone

Question 34

clay particle size; nonfissile, commonly with a massive or blocky texture

Answer 34

claystone

Question 35

characterized by its fissility (ability to split into thin sheets), generally parallel to bedding

Answer 35

shale

Question 36

with a well-developed cleavage, which may or may not be parallel to the bedding, and is commonly the result of metamorphism

Answer 36

slate

Question 37

process when calcite is easily replaced, often destroys the texture of the original carbonate

Answer 37

dolomitization

Question 38

what typically replaces original calcium carbonate

Answer 38

secondary dolomite

Question 39

what are the orthochemical components

Answer 39

microcrystalline ooze and sparry calcite cement

Question 40

a very fine-grained carbonate precipitate that has settled to the bottom of the basin

Answer 40

microcrystalline ooze

Question 41

coarser in grain size than the ooze and tends to be clear or translucent; a pore-filling cement that was precipitated in place

Answer 41

sparry calcite cement

Question 42

what are the 4 allochem components

Answer 42

intraclasts, oolites, fossils, and pellets

Question 43

fragments of weakly consolidated carbonate sediment that have been torn up, transported, and redeposited by currents within the basin of deposition

Answer 43

intraclasts

Question 44

in a size range of 0.1 to 1.0 mm in diameter, are spherical, show radial and concentric structures, and resemble fish roe. They are commonly formed by chemical accretion around nuclei such as shell fragments, pellets, or quartz sand grains

Answer 44

oolites

Question 45

remains of organisms

Answer 45

fossils

Question 46

well-rounded, homogeneous aggregates of microcrystalline calcite in a size range of 0.03 to 0.2 mm in diameter; feces of mollusks, worms, and crustaceans

Answer 46

pellets

Question 47

three types of limestone under folks classification

Answer 47

type 1 2 and 3

Question 48

consist of a matrix of allochemical constituents and sparry calcite cement

Answer 48

type 1

Question 49

variable percentage of allochemical grains in a microcrystalline matrix

Answer 49

type 2

Question 50

microcrystalline calcite matrix only (micrite)

Answer 50

type 3

Question 51

emphasizes the depositional texture

Answer 51

dunhams classification of limestone

Question 52

consists of more than 10% grains in a microcrystalline ooze (micrite)

Answer 52

wackstone

Question 53

grain-supported limestone with micrite matrix and sparry calcite cement

Answer 53

packstone

Question 54

grain-supported limestone with very little micrite.

Answer 54

grainstone

Question 55

a limestone made up of organic structures that grew in situ (in place), forming a coherent rock mass during growth

Answer 55

boundstone

Question 56

what is boundstones equivalent

Answer 56

biolithite

Question 57

formed by direct precipitation

Answer 57

orthochemical sedimentary rocks