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Geological Time 8
vocabulary practice
Question | Answer |
---|---|
Geology | a science that deals with the history of the earth as recorded in rocks |
absolute age | the age of a rock given as the number of years since the rock formed |
era | a major division of geological time |
eon | the longest division of geological time |
fauna | animal life; animals of a particular region or period |
flora | plants of a region or era |
fossil record | a historical sequence of life indicated by fossils found in layers of the Earth's crust |
geological time scale | A time scale established by geologists that reflects a consistent sequence of historical periods, grouped into four eras: Precambrian, Paleozoic, Mesozoic, and Cenozoic. |
law of superposition | in a sequence of sedimentary rocks, the oldest rocks are on the bottom and the younger rocks are on the top |
period | a unit of geological time during which a system of rocks formed |
radiometric dating | using a radioactive process to determine the age of an item |
relative age | the age of rock compared to the ages of other rocks |