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12 Cards in this Set
- Front
- Back
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What stage of the river does a waterfall form in? |
The youthful stage |
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Example of a waterfall |
Powerscours co wicklow |
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Waterfalls are a feature of _______ |
Erosion |
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What are the three main processes Involved in the erosion of a waterfall? |
•Hydraulic action •corrosion •solution |
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What is hydrologic action? |
This is the sheer force exerted by moving water.it is capable of freeing loose rock and soil from the river bed and banks. Soft rocks are eroded faster that hard rocks. |
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What is corrosion? |
Corrosion occurs when the rivers load ( sand, shingle, pebbles, rocks) is hurled against the bed and bank, wearing them away. This deepens and widens the river channel. |
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What is solution? |
Solution is erosion of rock by chemical means. When rivers flow over soluble rocks (e.g. limestone) the acid in the water dissolves the minerals in the rock. |
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Where do waterfalls form? P.2 |
Waterfalls form where there are alternate bands if hard and soft rocks. The soft rock is less resistant to errosion compared to the hard rock. |
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What is a gorge? |
A gorge is a narrow, vertical walled valley. |
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How to waterfalls form? |
The power of the water along with the process of solution begins to undercut the rock on the back wall of the waterfall. The hard rock begins to overhang the layer of soft rock. |
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Where does the waterfall move? |
The process that take place repeat themselves. The continues undercutting and collapsing causes the waterfall to retreat upstream. Leaving behind a gorge. |
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Is the base of the waterfall erroded? |
Yes. By the power of velocity ( hydrologic action and corrosion) from the falling river and it's load. A plunge pool then develops at the base of the waterfall. |
