Fossil Types


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Rock Types

Fossils are the rock-hard remains of once living plants and animals. Fossils are found worldwide, but they are not found in every type of rock. The chance that an organism will be preserved is rare. Fossils are found only in sedimentary rocks, such as limestone, sandstone, or shale. The processes that form metamorphic rocks destroys fossils, because of the extreem heat and pressure that is needed. So these organisms must be covered in silt, mud, or clay, before the slow process of mineralization could begin. Yet once formed, fossils are persistently assulted by normal geological processes such as erosion, weathering, further sedimentation, and leaching. So once formed, fossils can be lossed before anyone has the chance to find or examine them.