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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 vertebrate possessing two pairs of limbs, such as amphibians, reptiles, birds, and mammals.
a type of body fossil that forms when crystals fill a mold or sediments wash into a mold and harden into rock
Hollow in the ground in which natural tar accumulates by seepage.., Hollow in the ground in which natural tar accumulates by seepage
a white, radioactive metallic chemical element that weighs more than any other element in nature.
technique in which scientists calculate the age of a sample based on the amount of remaining radioactive isotopes it contains
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