2.A8 Glacial deposition creates distinctive landforms and contributes to the glacial landscape

Question 1

Meaning of the word moraine -

Answer 1

accumulated of glacial debris, where it is dumped by an active glacier or left behind. There are 4 types.

Question 1

The 4 types of Moraine -

Answer 1

Recessional, terminal, lateral and medial in lowland areas.

Question 2

Lateral moraine -

Answer 2

Located along the edge of valley glacier, where exposed rock on the valley slide is weathered and fragments fall down on the edge of the glacier it is carried along the valley and deposited when the ice melts. Parallel to ice flow

Question 3

Medial moraine -

Answer 3

A ridge of moraine down the middle of the valley floor, when two valley glaciers converge, two lateral moraines combine to form a medial moraine. The material is carried and deposited when melting occurs. Parallel to the ice flow

Question 4

Terminal or end moraine -

Answer 4

A ridge of moraine extending across the valley at the furthest point the glacier has reached. The advancing ice carries moraine forwards and deposits it at the maximum advance of when it retreats. Transverse to ice flow

Question 5

Recessional moraine -

Answer 5

A series of ridges running across the valley behind the terminal moraine. Each recessional moraine represents still-stand during ice retreat, good indicators of the cycle of advance and retreat many glaciers experience from accumulation and ablation. Transverse to ice flow.

Question 6

Drumlins -

Answer 6

Subglacial moraines primarily composes of lodgement till from glacier till under the glacier. In some instances the lodgement till is moulded into streamlined mounds called drumlins that have long axis. They are oval-shaped hills of often unsorted till the long axis runs parallel to the direction of ice flow.

Question 7

Lowland depositional features -

Answer 7

Till plains, lodgement and ablation till.

Question 8

Till plains -

Answer 8

Unconsolidated sediment deposited by a glacier. Mix of clay, boulders and gravel.

Question 9

Lodgement till -

Answer 9

Deposited under the ice therefore involved in the formation of a drumlin

Question 10

Ablation till -

Answer 10

Deposited by melting and ice usually has some evidence of deposition by running meltwater

Question 11

Erratics -

Answer 11

Erratics are large boulders transported and deposited by glaciers. Their presence and characteristics can provide clues about the former extent and movement of glaciers. For example, the presence of erratics composed of rock types not native to the area suggests long-distance glacial transport. An example could be the presence of granite erratics in areas where the local bedrock is limestone, indicating glacial transport from distant sources.

Question 12

Striations -

Answer 12

Created through rock friction showing the orientation if direct ice movement.