Transcription: Fossils are the remains or the marks of formerly living things. Most fossils form as part of sedimentary rock. This process begins when plant or animal remains are quickly buried in sediments, that is, the layers of mud or sand that settle out of water. After the remains are buried, mineral-rich water may seep down through the sediments and deposit its minerals in the remains. These minerals harden and strengthen the fossil. Over thousands of years, more and more sediment layers form on top of the layer containing the fossil. The weight of the upper layers presses down on the fossil-bearing se ...
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