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4.2.3 Fluvio-glacial and periglacial areas have distinct features. ContentField evidence to distinguish glacial landforms from fluvio-glacial landforms, to include stratified and unstratified drift, striations, varves, shape and size of materialGuidanceThere are opportunities for primary investig
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1. Fluvio-glaciation
2. 4.2.3 Fluvio-glacial and periglacial areas have distinct features Content
Field evidence to distinguish glacial landforms from fluvio-glacial landforms, to include stratified and unstratified drift, striations, varves, shape and size of material
Guidance
There are opportunities for primary investigation here. Material may display common orientation of elongated particles. Fluvio-glacial deposits are generally sorted, round and stratified. Glacial deposits are generally unsorted, angular and unstratified.
3. Lesson 1 By the end of this lesson you should be able to:
list the differences between glacial and fluvio-glacial landforms
explain the formation of varves
4. Characteristics of glacial and fluvio-glacial material
5. Differences between glacial and fluvioglacial material
6. Sandur Read p 345 Y & P, Collard p215-6
7. Erosional meltwater forms
8. Meltwater channels Read Prosser and Bishop p 149. Identify the 3 ways in which meltwater channels may be formed.
Using Murton Pike (Prosser) write a brief field guide to explain how to identify a meltwater channel.
9. Proglacial lakes
10. Before and after glaciation
11. Varves
12. Meltwater deposits
13. Meltwater channels
14. Eskers (Nova Scotia0
15. Eskers (NWT)
16. Eskers
18. Kames Kames are typically small hills a few metres to tens of metres tall, although some can achieve heights which are much taller. They form in the following manner: a stream at the top of the glacier intersects a crevasse, filling it with sediment. A stratification of the sediment forms; during times of higher ablation, larger particles are able to be entrained and thus deposited in the crevasse, whereas in times of lower discharge, more fines are deposited. As the glacier ablates, the sediment collapses into a hill. Kames, like eskers, are often mined for their sand and gravel deposits.
19. Kames in Greenland
20. Kame terraces in Strathspey The advance of Strath Spey ice across the mouth of Gleann Einich at around 14 kyr dammed a large glacial lake. This lake received sediments from the ice masses lying to the north and south and began to fill up. On the lake floor, fine-grained sands accumulated in the still water. Drop stones fell into the sand from floating ice bergs. Lake drainage was sudden and rapid flow left coarse gravels on top of the lake floor. Post-glacial river erosion has cut down into the former lake floor to leave a fine series of kame terraces.