Here is your short notes on Fossils

Fossils of certain animals and plants which are characteristic of certain geological horizons, beds or strata of rocks are called index fossils.

They have limited geological range or vertical distribution with a very wide geographical arrangement of occurrence indicating that they were short lived but had worldwide distribution.

The index fossils are useful in correlating the rock beds located miles away from each other in which they are preserved. A few examples along with their stratigraphic ages are given below.

Middle Devonian Lower Carboniferous Lower to Middle Permian Lower to Middle Permian Jurassic.

Lower Cretaceous Upper Cretaceous Upper Cretaceous Lower Eocene Lower Miocene