Rocks

Question 1

physical/mechanical weathering

Answer 1

biological (roots), exfoliation, frost wedging

Question 2

chemical weathering

Answer 2

oxidation, hydrolysis (water change structure), dissolution

Question 3

factors controlling weathering

Answer 3

type of rock/mineral, rock structure, rainfall/temp, vegetation

Question 4

formation of soil

Answer 4

in situ weathering

Question 5

controls of soil formation

Answer 5

time, topography, organisms, composition of bedrock

Question 6

soil composition

Answer 6

minerals (45%), water (25%), gases (25%), organic matter (5%)

Question 7

layers of soil

Answer 7

organic matter then top soil, subsoil, weathered rock, solid rock

Question 8

when does erosion happen

Answer 8

after weathering

Question 9

types of erosion

Answer 9

water, ice, wind

Question 10

depositional environment

Answer 10

lake, swamp, beach, river

Question 11

allochthonous

Answer 11

material from outside environment that blows to sea

Question 12

autochthonous

Answer 12

matter in ocean

Question 13

principle of superposition

Answer 13

oldest at bottom

Question 14

principle of horizontality

Answer 14

rocks layered horizontally

Question 15

geological archives

Answer 15

continuous accumulation of sediment, lakes/basins

Question 16

what do sediments contain

Answer 16

proxies

Question 17

biological proxies

Answer 17

pollen/diatoms

Question 18

chemical proxies

Answer 18

isotopes

Question 19

physical proxies

Answer 19

colour/grain size

Question 20

classifying sediments

Answer 20

clastic (over 2mm, conglomerate/breccia), organic (coal), chemical

Question 21

conglomerate/breccia

Answer 21

con is rounded coarse, breccia angular coarse

Question 22

formation of limestone

Answer 22

organisms with calcite shells accumulate together

Question 23

flintstone formation

Answer 23

diatoms have silica shells, when they die it accumulates as chert

Question 24

metamorphic diagenesis

Answer 24

occurs in sediments at less than 100C or less

Question 25

agents of metamorphism

Answer 25

temp/heat/fluids

Question 26

metamorphic changes

Answer 26

rotation/compression of crystals, new minerals, recrystallisation into bigger crystals, foliation

Question 27

types of metamorphism

Answer 27

regional (tectonic), contact, hydrothermal (mid-ocean ridge), shock (meteors)

Question 28

rock types

Answer 28

migamitite (highest grade), slate is lowest