Volcanoes

hotspring

waterfall

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Types of plate boundaries - Constructive plate boundaries - Destructive plate boundaries - Conservative plate boundaries

Types of plate boundary: destructive plate boundary

• Sulphuric gases -----> poison people• -----> acid rain• Lava---------------------> burns things---• Carbon dioxide------> greenhouse effect• Volcanic ash----------> mudflows-------

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• Geothermal power• Metals and Minerals• Fertile soil----------------• Tourist attraction

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When the river water is unable to remove the resistant rock layer but is enough to erode the soft rock downstream, the river falls down vertically in the form of a waterfall.

Middle course

Lower course

• Block: Water descends from a relatively wide stream or river.• Cascade: Water descends a series of rock steps.• Cataract: A large, powerful waterfall.• Chute: A large quantity of water forced through a narrow, vertical passage.• Fan: Water spreads horizontally as it descends while remaining in contact

with bedrock.• Frozen: Any waterfall which has some element of ice.• Horsetail: Descending water maintains some contact with bedrock. • Plunge: Water descends vertically, losing contact with the bedrock

surface.• Punchbowl: Water descends in a constricted form and then spreads out in

a wider pool.• Segmented: Distinctly separate flows of water form as it descends.• Tiered: Water drops in a series of distinct steps or falls. • Multi-step: A series of waterfalls one after another of roughly the same

size each with its own sunken plunge pool

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The falling water at the waterfall produces strong hydraulic action, forming a circular pool of water at the base of the waterfall called a plunge pool.

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