weathering

Question 1

what is sediment

Answer 1

sediments comprise loose fragments of rocks or minerals, shells and shell fragments, or mineral crystals that precipitate out of water

Question 2

how are sediments produced

Answer 2

sediment is produced by weathering

Question 3

sediment covers bedrock in

Answer 3

variable thicknesses

Question 4

what is weathering

Answer 4

weathering refers to the combination of processes that break up and corrode solid rock, and may eventually transform it in to loose debris or detritus

Question 5

in the pipe cleaner analogy

Answer 5

physical weathering is a drain snake
chemical weathering is drano

Question 6

physical weather is also known as

Answer 6

mechanical weathering

Question 7

boulder size

Answer 7

> 256mm

Question 8

cobble size

Answer 8

65-256mm

Question 9

pebbles size

Answer 9

3-64mm

Question 10

sand size

Answer 10

1/16-2mm

Question 11

silt size

Answer 11

1/256-1/16mm

Question 12

mud size

Answer 12

<1/256mm

Question 13

what does physical weathering do

Answer 13

breaks intact rocks in to unconnected clasts

Question 14

what is jointing

Answer 14

rocks buried deep endure enormous pressure and temperature

these rocks can be exhumed

the resulting change in P and T can cause the rock to change shape

natural cracks are known as joints

Question 15

sedimentary rock jointing

Answer 15

planar vertical joints

Question 16

igneous plutons jointing

Answer 16

exfoliation

Question 17

jointing turns intact bedrock in to

Answer 17

separate blocks

Question 18

what is frost wedging

Answer 18

water get in joints and freezes growing cracks by pushing rocks across

Question 19

what is salt wedging

Answer 19

dissolved salt precipitates out of water in open spaces in rock

the growing crystals push apart the rock grains

Question 20

what is root edging

Answer 20

as roots grow they exert a force on the surrounding rock

Question 21

what is thermal expansion

Answer 21

heat applied to a rock causes the outer layer to expand

Question 22

how does thermal expansion weather

Answer 22

day night cycles
forest fires

Question 23

what is chemical weathering

Answer 23

refers to a chemical reaction that alters or destroys minerals

Question 24

what the 5 commons types of chemical weathering

Answer 24

dissolution
hydrolysis
oxidation
hydration
organic influence

Question 25

hydrolysis is

Answer 25

water reacts with minerals and breaks them down to form other minerals

Question 26

oxidation is

Answer 26

reactions during which an element loses electrons
common in iron bearing minerals

Question 27

hydration is

Answer 27

absorption of water in to the crystal structure

causes some minerals to expand

clay (smectite)

expansion and dehydration can damage rock

Question 28

organic influence is

Answer 28

organisms play a role in chemical weathering process

Question 29

mafic minerals weather by

Answer 29

oxidation

Question 30

felsic minerals weather by

Answer 30

hydrolosis

Question 31

carbonate minerals and salts weather by

Answer 31

dissolution

Question 32

oxide minerals are resistant to

Answer 32

chemical weathering

Question 33

rate of weathering depends on

Answer 33

surface area to volume
preexisting weathering