Processes That Operate In The Glacier System And Landforms Created By Glaicier Erosions And Depositons

Question 1

What are the 3 main processes that operate from erosion?

Answer 1

Frost-shattering/ freeze thaw
Abrasion
Plucking

Question 2

What is frost- shattering/ freeze thaw

Answer 2

It describes that action of glacial meltwater on joints, cracks and holes in rocks.

Question 3

What happens when the temp is above 0 degrees

Answer 3

The water thaws and contracts and eventually causes rocks to break up

Question 4

What happens when the temp reaches below 0 degrees

Answer 4

The water cracks,freezes, expands and causes the crack to widen

Question 5

What is abrasion?

Answer 5

The moraine frozen into the glacier scours the valley sides and base. It’s a sand papering effect.

Question 6

What is plucking?

Answer 6

Water At the bottom of the glacier freezes onto rock on the valley base. As the glacier moves, the rock is pulled away from the valley base. It mostly occurs when the rock’s well jointed

Question 7

What are corries?

Answer 7

A corrie is a horseshoe-shaped valley which is formed through erosion by ice or glaciers

Question 8

How does a corrie form

Answer 8

Snow gathers in a hail and turns into ice
Material from the base of the hollow is plucked out by the ice and erases the hollow to make it deeper
Eventually, the ice outgrows the hollow and goes down slope due to gravity
When the ice melts, it leaves a deepened hollow called a corrie which sometimes fills up with water to form a lake which is called a torn

Question 9

What is an aréte?

Answer 9

Knife edged ridge formed between two corries

Question 10

How does an aréte forms?

Answer 10

When two corries form next to each other and their adjacent walls are eroded backwards until they melt, a narrow and pointed rock ridge is formed

Question 11

What are pyramidal peaks?

Answer 11

It’s formed when 3 corries are formed back to back

Question 12

What are 3 landforms created by deposition?

Answer 12

Moraines
Drumlins
Erratics

Question 13

What are moraines?

Answer 13

Type of landform that’s created when a glacier deposits the material that it has been transporting and is made up of unsorted angular rocks

Question 14

Name a few types of moraines

Answer 14

Terminal
Ground
Lateral
Medial
Recessional

Question 15

What are terminal moraines

Answer 15

Found at furthest end of a glacier

Question 16

Ground moraines

Answer 16

Disorganised piles of rocks of various shapes, sizes and rock types found on the ground

Question 17

Lateral moraines

Answer 17

Found along the sides of a glacier

Question 18

Medial moraines

Answer 18

Found at the junction between two glaciers

Question 19

Recessional moraines

Answer 19

Material found at the snout of the glacier as it retreats/advances

Question 20

Drumlins

Answer 20

Smooth mound of deposited material that reach a kilometre or more in length, 500m in width and over 50m in height

Question 21

What is a group of drumlins called?

Answer 21

A swarm

Question 22

What are striations?

Answer 22

Scratches on material that the glacier is carrying which give an indication of the direction the glacier was travelling in.

Question 23

Erratics

Answer 23

Large boulders that have been carried by the glacier and then deposited in an area of different rock types so they look completely out of place

Question 24

U shaped valley

Answer 24

As glaciers move down they change v shaped valleys to a U one of glacier troughs

Question 25

Formation of a u shaped valley

Answer 25

Before glaciation a v shaped valley is formed by a river. During an ice age a glacier moves down this valley
Rocks trapped in the bottom of the ice acts like sandpaper wearing away the valley through abrasion
The glacier deepens, straightens and widens the valley by abrasion
After the ice melts a u shaped valley remains