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geologic time
geologic time
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Introduction References & Edit History Quick Facts & Related Topics
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Quizzes
Cross section of Earth showing the core, mantle, and crust
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Pangaea (Pangea) was a supercontinent 225 million years ago formed by plate tectonics and continental drift.
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4:045 Dinosaurs: Monsters of the Past, Tyrannosaur, Trachodon, Triceratops
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Still from the film Deliverance, 1919. The story of Helen Keller and Anne Sullivan. View shows Keller in the cockpit/front seat of an airplane.
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Animals & Nature

geologic time

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Also known as: geological time scale
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geologic time
geologic time
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Category: Animals & Nature
Related Topics:
Precambrian
geochronology
Mesozoic Era
Phanerozoic Eon
Lipalian interval
On the Web:
Academia - The significance of Geological Time (Feb. 16, 2024)
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geologic time, the extensive interval of time occupied by the geologic history of Earth. Formal geologic time begins at the start of the Archean Eon (4.0 billion to 2.5 billion years ago) and continues to the present day. Modern geologic time scales additionally often include the Hadean Eon, which is an informal interval that extends from about 4.6 billion years ago (corresponding to Earth’s initial formation) to 4.0 billion years ago. Geologic time is, in effect, that segment of Earth history that is represented by and recorded in the planet’s rock strata. The geologic time scale is the “calendar” for ...(100 of 313 words)

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