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| Pregunta | Respuesta |
| Explain how corries (cirques) are formed | Glaciers normally form on one side of a mountain peak - the side that gets the least sun and the coldest winds. That's where there's most accumulation and least ablation. Snow collects in hollows and turns to ice. Basal sliding with abrasion and plucking deepens the hollow into a corrie (a bowl shaped hollow) When the ice in the corrie is thick enough, it flows over the lip and downhill as a glacier. Frost shattering and plucking steepen the back wall of the corrie. |
| What is an arête and how is it formed? | This is a steep sided ridge and it is formed when two glaciers flow in parallel valleys. The glaciers erode the sides of the valley, which sharpens the mountain ridge in between them |
| What is a pyramidal peak and how is it formed? | This is a pointed mountain peak with at least three sides. It forms where thee or more corries form back to back (their back walls make the mountain peak) |
| What are glacial troughs (or U-shaped valleys) and how are they formed? | These are steep sided valleys with flat bottoms. They're formed by the erosion of V-shaped river valleys by glaciers. As the glacier erodes through the V-shaped valley, it makes them deeper and wider. |
| What are hanging valleys and how are they formed? | These are formed by tributary glaciers - they erode the valley floor much less deeply as they're smaller than the main glacier. So, when the glaciers melt, the valleys get left at a higher level than the glacial trough formed by the main glacier. You get waterfalls from hanging valleys into the main glacial trough. |
| What are truncated spurs and how are they formed? | These are formed when ridges of land (spurs) that stick out into the main valley are truncated (chopped off) as the main valley glacier moves past. |
| What are valley steps and how are they formed? | These are steps in the glacial trough. They're formed when the glacier erodes the valley floor more deeply. This happens when another glacier joins it or when there's less resistant rock. |
| What are tarns and how are they formed? | These are lakes that form in corries after a glacier has retreated |
| What are ribbon lakes and how are they formed? | These are long, thin lakes that form after a glacier retreats. They form in dips caused by erosion of bands of less resistant rocks, or behind dams of moraines left by the glacier |
| What are fjords and how are they formed? | These are long, deep inlets that form when a valley that's been eroded by a glacier is flooded by sea level rise after the ice has melted |
| What is a roche moutonnée and how is it formed? | This is a resistant mass of rock on the valley floor. The upstream side is smooth as it was smoothed by abrasion as the glacier went over it. The downstream side is steep and rough where the glacier plucked at it. |
| What does moraine mean? | This is the name for different formations of till deposited by a glacier as it melts. |
| Name and explain the different types of moraine | Lateral moraine is deposited where the sides of the glacier were Medial moraine is deposited in the centre of the valley where two glaciers converge (the two lateral moraines join together) Terminal moraine builds up at the end of the glacier, and is deposited as semicircular hillocks of till |
| What is till? | This is the stuff that a glacier leaves behind - unsorted boulders, stones and clay. |
| What are drumlins? | These are half-egg shaped hills of till, up to 1500m long and 100m high. The upstream (stoss) end is wide and tall, and the downstream (lee) end is narrow and low. They often form in groups. |
| What are erratics? | These are rocks that have been picked up by a glacier or an ice sheet, carried along and dropped in an area of completely different geology. |
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