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a shape of the land such as a mountain, plain or plateau


a mountain formed by hardened lava with an opening through which lava, ashes, rocks and other materials may come out


the shaking of the ground caused by rock movement along a fault


a crack in the earth's crust along which rocks move.


the moving of weathered rocks and soil by wind, water or ice


a pile of sand formed by the wind


nonliving solid matter from the earth


the breaking and changing of rocks

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