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Geology 101 UND
Ch. 1
Question | Answer |
---|---|
asthenosphere | a subdivision of the mantle below the lithosphere. weak material, 100-700Km deep, rock is easily deformed |
continental shelf | gently sloping submerged portion of continental margin extending from shoreline to continental slope |
deep-sea trench | narrow elongated depression of seafloor |
hypothesis | tentative explanation that is then tested to see if valid |
igneous rock | rock formed by crystallization of magma |
inner core | solid innermost layer of earth |
lithosphere | rigid outermost layer of earth includes crust and upper mantle |
magma | body of molten rock found at depth including any undissolved gases and crystals |
mantle | one of earth's compositional layers solid rocky shell extends from base of crust to 2900Km depth |
metamorphic rock | rock formed by the alteration of preexisting rock by heat pressure and chemically active fluids |
mid-ocean ridge | continuous mountain ridge on ocean floor rifts at crests of ridges represent divergent plate boundaries |
nebular hypothesis | model for origin of solar system supposes a rotating nebula of dust and gases that contracted to form sun and planets |
oceanic ridge | see mid ocean ridge |
outer core | layer beneath mantle 2270 Km thick has properties of a liquid |
relative dating | rocks are placed in proper sequence or order only chronological order is determined (not exact age) |
sediment | unconsolidated particles created by weathering and erosion of rock by chemical pppt from soln in water or from organisms transported by water wind or glaciers |
sedimentary rock | rock formed by weathered products of preexisting rocks that have been transported deposited or lithified |
shield | large relatively flat expanse of ancient igneous and metamorphic rocks within craton |
theory | well tested widely accepted view of observable facts |
uniformitarianism | concept that the processes that shape earth in geologic past are the same operating today |
weathering | disintegration decomposition of rock at or near the surface of earth |