The use of ground-penetrating radar to detect cultural features: Ceren, El Salvador

Ground penetrating radar (GPR) has become an exceedingly valuable tool in archaeological research. This thesis presents the recent re-analysis of all ground penetrating radar data from the site of Ceren in El Salvador. The Ceren site is unique in its extraordinary preservation due to the approximately 6 meters of volcanic ash that blankets this prehistoric site. Geophysical techniques have been employed at Ceren since 1979 to facilitate the location of the structures and topographic variation of this ancient village. Ground penetrating radar has provided the most fruitful data of the geophysical techniques used at Ceren. While GPR was once operated in archaeology only for "anomaly hunting," researchers are being to recognize the utility of this technique to map paleo-topography and identify specific subsurface features (Conyers 2004). The aim of this thesis is to advance the foundational work of Dr. Lawrence Conyers, who first collected and analyzed a large portion of the data presented here when GPR software was still rudimentary, by completely re-analyzing his original dataset for evidence of archaeological features at Ceren (Conyers 1995).; Each GPR reflection from the Ceren data set was examined to locate various anomalies or features within the images. To establish confidence levels in the interpretations of each anomaly, categories of probable, possible, and questionable were defined based on the presence of anomalies in a various number of reflections, correlation of specific anomaly shape to real features, and limited computer modeling. One of the most important contributions of this thesis is the recognition that agricultural fields are visible in GPR imagery. These agricultural fields, as well as structures, compacted surfaces, and activity areas represent the array of archaeological features associated with the GPR anomalies documented in this thesis. Such data has important implications for site size, settlement patterns, subsistence organization, and spatial layout of the village. GPR reflections from the Ceren survey grids contribute considerably to our understanding of the Ceren village landscape, the possibility of correlating GPR images with specific archaeological features, and the indications of areas for future survey and excavation at the site.