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the process of turning some plant material into stone by infiltration with water carrying mineral particles without changing the original shape
a type of body fossil that forms when crystals fill a mold or sediments wash into a mold and harden into rock
formed when a dark sticky form of oil seeps up from underground causing animals to get stuck.
A vertebrate possessing two pairs of limbs, such as amphibians, reptiles, birds, and mammals.
any indirect evidence of life preserved as an impression in rock; trails, footprints, tracks, burrows, and bite marks
Geologic time scale
scale used by paleontologists to represent evolutionary time, Earth's history organized into four eras: Precambrian, Paleozoic, Mesozoic, and Cenozoic
a technique used to determine the actual age of a fossil on the basis of the amount of a radioactive element it contains
a white, radioactive metallic chemical element that weighs more than any other element in nature
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