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a crack in the Earth's crust


shaking of Earth's crust


mountain made from the lava, rocks, and ash that spewed from an active volcano


magma-hot, melted rock beneath Earth's surface lava-magma that flowed onto the surface of the Earth


the earth's surface is worn away by the action of water and wind


the breaking down of rocks and other materials on the Earth's surface.


the natural process of sediment (dirt) moving down a river and being deposited (dropped) to make new soil


something built to stop flow of water


a bank built beside a river or stream to prevent overflow.

storm drain

an opening built to collect runoff (rain), which then flows into an underground system.

beach reclamation

sand pumped to a beach area to restore the beach as it once was prior to beach (sand) erosion caused storms, winds, tides

constructive force

a force that builds up features of the Earth's surface

destructive force

a force that wears away mountains and other features on the surface of the Earth


small, solid pieces of material that come from rocks or living things- dirt


a type of wall built out into water to protect a coastline or restrain currents

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