Sedimentary Textures

Question 1

5 parameters of sedimentary texture

Answer 1

1. grain size
2. grain shape
3. grain orientation
4. porosity
5. permeability

Question 2

a diagram that describes particle sizes in epiclastic rocks and classifies them on a logarithmic phi scale

Answer 2

Udden-Wentworth Scale

Question 3

phi value formula

Answer 3

-log₂d

Question 4

component of detrital sedimentary rocks with sizes ranging from sand to gravel

Answer 4

clasts

Question 5

component of detrital sedimentary rocks that are mud sized

Answer 5

matrix

Question 6

measure of particle population that represents the typical particle size

Answer 6

central measure

Question 7

bar graph that compares the weight percentage vs the phi value of clasts

Answer 7

histogram

Question 8

line graph that compares the weight percentage vs the phi value of clasts

Answer 8

frequency curve

Question 9

line graph that shows the cumulative weight percent of all sizes coarser than the size under consideration

Answer 9

cumulative curve

Question 10

most abundant particle size

Answer 10

mode

Question 11

average size of particles

Answer 11

mean

Question 12

average diameter of particles

Answer 12

graphic geometric mean

Question 13

method of passing soil and sediment through a series of stacked mesh

Answer 13

sieving

Question 14

factors affecting shape

Answer 14

1. lithology
2. hardness

Question 15

spheroid, similar in all directions

Answer 15

equant

Question 16

rod shaped, elongate that have on axis much longer than the other two

Answer 16

prolate

Question 17

disk shaped, flattened cylindrical where two axes are shorter than the other

Answer 17

oblate

Question 18

flattened shaped where three axes have different lengths

Answer 18

bladed

Question 19

the more travelled a sediment is the more ____ it is

Answer 19

rounder and spheroidal

Question 20

distribution of grain sizes present within a rock

Answer 20

sorting

Question 21

quick method of determining the phi size value for any percentile

Answer 21

sorting coefficient

Question 22

more complicated measure that involves finding values that are in standard deviation to the mean

Answer 22

inclusive graphic standard deviation

Question 23

volume of void space in a rock

Answer 23

porosity

Question 24

arrangement of grains in a rock

Answer 24

packing density

Question 25

the denser the packing, the _____ the porosity

Answer 25

lesser

Question 26

porosity associated with the original depositional texture

Answer 26

primary porosity

Question 27

porosity developed after deposition and burial

Answer 27

secondary porosity

Question 28

degree of how much fluids can pass through the rock

Answer 28

permeability

Question 29

property of a curve having many turns

Answer 29

tortuosity

Question 30

extent of how much the sediment of a rock has undergone change

Answer 30

maturity

Question 31

the degree of maturity that indicates a rocks’ transportation history

Answer 31

textural maturity

Question 32

the degree of maturity based on a rocks’ composition

Answer 32

compositional maturity

Question 33

the more ______ a rock has the more compositionally mature it is

Answer 33

quartz