A living thing dies on land or in the sea and it gets covered by a layer rock or soil., Some parts of the body decay and, ussually, only the skeleton is left., Over a very long time, the bones break down and leave a space in the Earth, like an empty mould., Over thousands of years the mould fossil might become a cast fossil with sediment entering the mould., As erosion and weathering takes place, eventually the fossils become exposed..

Fossilisation process

Tulostaulu

Visuaalinen tyyli

Vaihtoehdot

Vaihda mallia

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