Abstract/Summary

This research explores the efficacy of gamma radiation surveys as a complementary tool to established geophysical methods used in non-intrusive archaeological investigations. It represents the first reported study of this portable methodology in an archaeological context, with results demonstrating alignment with, and providing additional insights that are complementary to, other traditional methods. This research tests the hypothesis that historic human activities can influence concentrations of naturally occurring radionuclides in the ground, and that these changes can be measured using portable gamma radiation surveying methods. Data processing then enables the visualisation of these changes. Surveys were undertaken using Groundhog, a rugged gamma radiation detection system designed for the nuclear industry, at Bisham, Silchester and East Heslerton. These sites were chosen to test the technique on known targets with diverse characteristics. Data was processed using ArcGIS and Geoplot to create gamma radiation distribution maps that enabled identification of anomalies corresponding to known archaeological features. XRF data from environmental and archaeological samples, as well as desktop study data, were analysed to help interpret and understand these observations. Results indicate that larger features such as roads, ditches and historic field boundaries can be delineated in the gamma radiation data. Other contextual information, such as transitions in geological conditions can also be identified. Accrued data was used to develop a high level model to help predict the influence of different combinations of soil and target types on the effectiveness of the technique. This insight can be used to guide the selection of future sites used in further research. Findings from this research project suggest that portable gamma radiation surveying could offer a novel complementary tool for archaeological prospection, providing additional interpretive value for existing geophysical outputs. Opportunities have been created for further investigation, particularly in refining the method and its application in diverse archaeological contexts.