Different types dating techniques used archaeology
This closely agrees with the fact that the seals from Indus Valley style from Ur, Kish and Tell Asmar and other sites fall within the range of 2500-1500 B. When a group or type of objects are found together under circumstances suggesting contemporanity they are said to be associated.It is nearly always association with other phenomena that gives a first clue as to the use, the age and chronological attribution of a potential datum, but age at least may sometimes be inferred from position in a geological deposit or a layer of peat.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.Astronomical data have been applied in the study of geological ice ages by calculating the curves for major fluctuation of solar radiation.Consequently, the chronology worked out for the geological deposits helped in dating the prehistoric tools found in these deposits. There are certain antiquities and potteries which by themselves have acquired a dating value.In such cases subjective element cannot be ruled out.But, for a single culture site the method is quite reliable.
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.
The various methods of relative dating are; This method depends on the common observation that the height of the habitational area increases as the people continue to live at the same place.
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.
Charred bones are better preserved and are therefore relatively more reliable.