Preliminary results of three-dimensional GPR-based study of a prehistoric site in Barbados West Indies

摘要

Prior results of surface artifact collecting, test excavations, and auger sampling on an archaeological site in Barbados suggested that we experiment with GPR as a method to target areas for future study. The site is associated with village occupations of Amerindians that are dated to between approximately 2000 and 500 years ago. Archaeological features include burials, hearths, ceramic lined wells and post holes. Artifact middens contain pottery sherds, conch shells, and other marine resource debris. The site selected was located at the southern tip of Barbados and is situated on a deep stabilized surface behind a large active dune system. The soil layer consists of dry, clean quartz sand. We obtained limited ground truth at the site by hand-auguring in areas of field- identified anomalies, and by auguring control holes away from anomalies. Anomalies were almost always large diffractors such as conch shells and rocks. We used 3D software to perform standard processing enhancements and to assemble the parallel lines into three-dimensional volumes. The dimensions, distribution, and shapes of time-sliced amplitude anomalies were consistent with those of previously excavated burials, poles, and pit structures. These features would not have been obvious using conventional a profile-based GPR survey.