years around the world, on the basis of stratigraphic correlation, has permitted geologists to show a relationship between rock units and to split them into time units. All periods on the geologic column don’t last for the same amount of time as it splits relative geologic time into identified relative age units.
The method of creating equivalency of rock ages, units, events in history of geology (for example events pertaining to the structure or movement of the earths crust, faults, unconformities, and so on.) and depositional environments in different areas is called as correlation.
Fossil organisms are very useful in correlating strata because these have specific characteristics (for example assemblages of organisms and have great diversity) of beds that is deposited at some point in specific geologic