Definition of chronometric dating
The earliest evidence of writing anywhere in the world only goes back about 5000 years.
Paleoanthropologists frequently need chronometric dating systems that can date things that are many thousands or even millions of years older.
It is based on the fact that amino acids (the building blocks of all proteins) exist in two mirror image forms, both of which otherwise have the same chemical structures.
It implies that relative dating cannot say conclusively about the true age of an artifact.However, archeologists still require further information to find out the items that are oldest and those that are youngest in the order.It is left for absolute dating to come up with the precise age of an artifact.The time between reversals has ranged between less than 100,000 to tens of millions of years with an average of about 300,000 years. It takes 1,000-8,000 years for one to be completed. It is thought that as a reversal approaches, the earth's magnetic field weakens.It has been gradually weakening for the last 250 years.