Principles Of Geology

The science of geology can be used for a variety of purposes. At a core level this science can tell us all about how old the Earth is and how it was formed over time. It can also be used to specifically assess areas of land and can identify areas of natural resources and precious metals.

Geologists use a series of known geological facts to help them in their work. These facts have been developed over centuries and are known as the principles of geology or geological principles. These principles help geologists date specific areas and work out how they were originally formed.

Some of the better known geological principles include:

Cross cutting relationships - this principle helps a geologist work out the age of a fault in the Earth. In general terms if you have a rock that is cut through by a fault then the fault will have been created later than the rock.
Faunal succession - this principle uses the presence of fossils to help date rock formations.
Inclusions and components - this principle states that if a sedimentary rock contains an inclusion of another material then this inclusion will be older than the rock that holds it.
Intrusive relationships - here a geologist can work out that a layer of igneous material that cuts into a sedimentary rock will be younger than the rock it cuts into.
Superposition - this principle shows that layers of sedimentary rock that have not been disturbed over time will be composed of layers by age.
Uniformitarianism - this principle states that the geological systems that have shaped the Earth at a current moment in time are the same as those that shaped it historically.