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6 Cards in this Set
- Front
- Back
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Where do meanders and oxbow lakes form? |
Meanders and ox bow lakes form in the middle and lower courses. |
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How are meanders formed from erosion and deposition? |
When the current is faster on the outside of the bend because the river channel is deeper (and less friction to slow the water down) Therefore more erosion takes place on the outside of the bend forming river cliffs.
The current is slower on the inside of the bend because the river channel is shallower ( there's more friction to slow the water down).
So eroded material is deposited on the inside of the bend forming slipe-off slopes. |
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How are 0x-bow lakes formed from Meanders? |
Meanders get larger overtime and eventually turn into a oxbow lake. Firstly, erosion causes the outside bends to get closer until there's only a small bit of land left at the neck. The river breaks through and the river flows the shortest course. Deposition eventually cuts off the meander forming a ox-bow lake. |
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How are waterfalls formed?
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Waterfalls form then a river flows over a area of hard rock followed by an area of soft rock. The soft rock is eroded more by the river forming a 'step' in the river. As the water goes over the step the soft rock is eroded even more. A step drop is eventually created called a waterfall.
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How are gorges formed from waterfalls? |
Gorges are formed from waterfalls because the hard rock of the waterfall is eventually undercut by erosion. It becomes unsupported and collapses. The collapsed rocks are swirled around at the foot of waterfall, then they're eroded by the soft rock by abrasion. Creating a plunge pool. Over time the waterfall will retreat leaving behind a steep sided gorge. |
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What is a floodplain? |
The area that a river floods is called a floodplain. |
