Relative dating methods in archaeology
The quantity of the C-14 remaining is measured by counting the beta radiation emitted per minute per gram of material.Modern C-14 emits about 15 counts per minute per gram, whereas Carbon-14 which is 5700 years old, emits about 7.5 counts per minute per gram.Even when the absolute dates are available, we have to supplement the information with relative dating.
With the aid of these dated imports it was possible to date the associated Indian objects to the first two centuries A. Similarly NBP and PGW has helped in fixing the chronology of numerous sites. Sometimes dates are also obtained with the assistance of astronomy.The deposit thus occurring forms layers depending on the nature of the material brought in by the people inhabiting the area.According to this method, the upper deposits are younger and the lower deposits are older.Specimens of organic material which can yield good amount of carbon can be collected for C-14 dating.For example charcoal, wood, shell, paper, leaves, cloth, animal hair, bone, pollen, tooth, iron, prehistoric soot from the ceiling of the caves practically any material containing some carbon can be subjected Bones are generally affected by ground water carbonates and are therefore least reliable for dating.
The types and forms or shape of these pots and also the antiquities under go evolutionary changes in cource of time, It is further assumed that all living animals derive body material from the plant kingdom, and also exhibit the same proportion of C-14 material.