Friday, 6 December 2013
How fossils are formed
Hopefully this gif explains it but in case it's not clear...
When an animal dies, its skeleton settles on the ground/sea floor and is buried by sediment.
The sediment begins to thicken and gradually turns to stone.
Over time the groundwater dissolves the skeleton and a mould of the skeleton is formed.
Minerals crystallise inside this mould and a cast of the skeleton is formed.
Eventually this fossil is exposed on the Earth's surface either from natural erosions or from excavations.