Geosphere- Rock Cycle Pt 2

Question 1

weathering vs erosion

Answer 1

weathering= how water/ wind etc attack and break down a rock

erosion= the removal of the broken down rock by wind/ water etc

Question 2

mechanical weathering=

Answer 2

physically breaking down by a process (like wind)

Question 3

chemical weathering=

Answer 3

water/ atmosphere undergoes a chemical rxn with the rock to break it down

Question 4

what are 3 products of weathering (that can be removed by erosion)?

Answer 4

regolith, soil, sediment

Question 5

what are the 4 processes of mechanical weathering?
Products?

Answer 5

1. frost action
2. abrasion
3. pressure release
4. biological effects

products= rock and mineral products

Question 6

How does frost work to mechanically weather a rock?

Answer 6

water/ frost gets into the cracks in a rock
- the temp goes above and below zero
- when water freezes, it expands and fractures the rock into smaller pieces

Question 7

How does abrasion work to mechanically weather a rock?

Answer 7

particles of rock collide with other particles of rock
- common on coastlines: water vs rock and rock particles in the water vs rock
caused by energy from waves

Question 8

How does pressure release work to mechanically weather a rock?

Answer 8

rocks created under the surface (high pressure): when they come to the surface, they expand a bit b/c of less pressure. this causes them to crack and exfoliate (peel)

-smooth, rounded rock surface where sheets have exfoliated in the past

Question 9

How do biological effects work to mechanically weather a rock? Give an ex

Answer 9

eg. invasive tree roots- work their way into rocks and fracture them further

Question 10

____ materials chemically weather a rock. List 3 of those materials
What are 2 products that form from chemical weathering?

Answer 10

raw

1. gases from atmosphere like CO2
2. water
3. minerals

products:
1. new minerals (via reaction)
2. ions in solution

Question 11

____ is very vulnerable to chemical weathering because it’s slightly ___, so reacts with __

Answer 11

limestone
acidic
calcite

Question 12

dissolution of CO2 in water forms a ___ ___
- common ___ weathering

Answer 12

weak acid

chemical

Question 13

chemical weathering of feldspar produces ___ ____

Answer 13

new minerals (clay minerals)
eg sheet silicates

Question 14

regolith=

Answer 14

products of weathering that has not been moved yet

Question 15

soil=

Answer 15

products of weathering plus organic matter from plants

Question 16

-
-
-

Answer 16

• gravity (fall off a cliff)
• moved by water
• moved by ice (glaciers)
• moved by wind

Question 17

____ currents transport sediment in water down the continental slope to “deep-sea fans”

Answer 17

turbidity

Question 18

how were turbitity currents discovered?

Answer 18

not discovered until 1930’s when a turbidity current took out the underwater phone lines b/w US and Europe

Question 19

Flow of ice is ____ (__-___)
glacial deposits are ___ till

Answer 19

laminar (non-turbulent)

unsorted till- huge range of grain size b/c no mechanism to sort them (the transport mechanism is a SOLID)

Question 20

Sediment transport by water:
- speed/ energy determines ___-___
- duration/ energy of flow determines ___

Answer 20

grain-size
sorting

Question 21

if the sediment in a river is very well sorted, what does that imply?

Answer 21

it has been flowing for a very long time (well sorted)

Question 22

T/F
sediment transported by wind tends to be rounded and not well sorted

Answer 22

false

It does tend to be rounded (mechanical abrasion)
but
It is also well sorted because wind can only carry a certain size

Question 23

how do non-clastic sedimentary rocks form?
give 5 examples

Answer 23

form from chemical or biochemical reactions

• carbonate
• organic (coal)
• siliceous
• iron rich sediment
• evaporites