How do fossils form layer by layer?

Answer 1

Before 100 million years ago.Some invertebrates on the sea-bed die,and are buried in the sand.More sand accumulates,and sandstone forms under pressure.

Millions of years later,dinosaurs living in the area die,and their bodies,too,are buried in mud.This mud is also compressed into rock,above the rock containing the earlier invertebrate fossils.

Again millions of years later,the bodies of horse-like creatures dying in the area are fossilised in rocks above these earlier rocks.

Much later,By erosion or water flow wears away some of the rock and exposes the horse-like fossils.As we dig deeper,we will find older and older fossils.

Answer 2

Fossils form layer by layer through a process called sedimentation. When an organism dies, its remains can become buried in sediment that accumulates over time. As more layers of sediment build up above, the remains can be compressed and eventually mineralized, creating a fossil. The fossil is preserved in the rock layers, providing a snapshot of the past.