Radiocarbon Dating of Arid Zone Deposits

The technique of radiocarbon dating has now been in existence for almost 50 years and its advent has resulted in major advances in the fields of archaeology and landscape evolution. However, the fact that most fossil materials form an open system with respect to environmental inorganic and organic carbon has been a distinct disadvantage in its use. The message that many published radiocarbon dates do not actually date the event they are supposed to has not been spread as widely as it should have been. There still seem to be users willing to build a story around a series of radiocarbon dates rather than first building a story around their own research and then testing the radiocarbon dates to see if they fit. The most straightforward aspects of obtaining radiocarbon dates are the sample collection and the measurement of the radiocarbon concentration. The other components of the system, such as interpretation of the collection site to correlate the relationship between sample and event, pretreatment of samples to remove components not associated with the event being dated, and final interpretation of results must never be regarded as straightforward. This paper summarises the development of the measurement techniques used in radiocarbon dating and reviews many of the approaches that have been used in an attempt to isolate material representative of the event to be dated. There are still advances that can be made in the pretreatment and purification of samples for dating. This paper will provide an insight into possible strategies needed for this development.