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crater – n. a large round hole in the ground made by the explosion of a bomb or by something falling from the sky
meteor – n. a rock from outer space that becomes very hot and burns brightly in the sky as it enters Earth's atmosphere
sediment – n. a solid substance that forms a layer at the bottom of a liquid
megaflood – n. a large, catastrophic flood
deposit – n. a layer of a substance that has developed from a natural or chemical process
impact – n. ta powerful effect something has on a particular person or situation
roar – v. moving fast and in a powerful way
gigantic – adj. very large
geologic – adj. the study of the rocks and similar substances that make up the Earth's surface
habitable – adj. able to support life
