Many archaeological dating methods help to establish relative, absolute, and chronometric chronologies. Excavation archaeology utilizes techniques such as dendrochronology, radiocarbon analysis, luminescence dating, electronic spin resonance, uranium-series dating, and optical analysis, among others, in order to establish the real age of artifacts and the duration of historical periods from which they came (Fagan and Durrani 105). The aim of this paper is to discuss one of the most reliable tools of chronometric chronology—radiocarbon dating. It will also describe the use of accelerator mass spectrometry (AMS) radiocarbon dating for establishing the age of beeswax figures and charcoal paintings in the Kimberley region of Western Australia.
Overview
Radiocarbon analysis is a dating method based on radioactive decay of carbon. The technique was developed by two English physicists Arnold and Libby, in 1949 (Fagan and Durrani 117). The method is based on the property of cosmic radiation that makes possible the creation of carbon isotope carbon 14 through the reaction with nitrogen (Fagan and Durrani 117; Staller et al. 131). Therefore, the nucleus of carbon 14 or C-14 is not as stable as other isotopes, which means that it is exposed to radioactive decay that can be easily measured. Taking into consideration the fact that C-14 is being absorbed by vegetation and animals consuming organic matter, it is possible to date bones, wood, and other remains of plants such as charcoal to more than 50, 000 years ago (Fagan and Durrani 117; Wills par. 2).
According to Coleman and Fry, in order to have a solid understanding of ecosystem functioning, it is necessary to know “the real amount of carbon that circulates within the system is needed” (31). Carbon analysis can be applied to multiple spheres enhancing the understanding of natural cycles, periods of glaciations, and the origin of life on Earth. However, radiocarbon dating not only makes it possible to find new paths to the past but also helps to verify earlier chronologies. For instance, since 1990, there was a wide-spread perception that a region in Iberia was the land where late Neanderthals settled (Wood et al. 2783). However, as Wood et al. found out, “with doubt cast over the late survival of Neanderthals, the place of southern Iberia in these arguments must be viewed cautiously” (2783).
Kimberley
According to Aubert, AMS radiocarbon dating was extremely effective in establishing the age of beeswax silhouettes and charcoal paintings in the Kimberley region of Western Australia (574). The archaeologists determined that beeswax paintings were made with plant resin, which is a carbon-bearing substance. Moreover, in order to draw a painting with wax, it has to be fresh. It means that the age of 3780 +- 60 years BP established by radiocarbon is the actual age of paintings (Aubert 575). On the other hand, the charcoal pigment that was used to produce handprints does not allow for such precise analysis. It has to do with the fact that long-lived trees have rings that stop absorbing C-14 once they are fully formed. It results in a significant difference between the time of their growth and the time of their decay (Aubert 575). Therefore, the radiocarbon estimate of the age of charcoal paintings is 120 +- 140 years (Aubert 575).
Conclusion
Radiocarbon analysis continually helps scientists see the history from a new perspective by substantially contributing to multiple archaeological breakthroughs. It is also a very “sharp focus technique” (Feder 4) that allows us to reconcile very tiny elements with large historical scales.
Works Cited
Aubert, Maxime. “A Review of Rock Art Dating in the Kimberley, Western Australia.” Journal of Archaeological Science, vol. 39, no. 1, 2012, pp. 573-577.
Coleman, David, and Brian Fry. Carbon Isotope Techniques. Academic Press, 2012.
Fagan, Brian, and Nadia Durrani. Archaeology: A Brief Introduction. Routledge, 2016.
Feder, Kenneth. The Past in Perspective: An Introduction to Human Prehistory. 6th ed., Oxford University Press, 2016.
Staller, John, et al. Histories of Maize in Mesoamerica: Multidisciplinary Approaches. Left Coast Press, 2010.
Wills, Matthew. “Radiocarbon Dating at 75.” JSTOR Daily, Web.
Wood, Rachel, et al. “Radiocarbon Dating Casts Doubt on the Late Chronology of the Middle to Upper Palaeolithic Transition in Southern Iberia.” PNAS, vol. 110, no. 8, 2012, pp. 2781–2786.