ARCHAEOLOGY STUDIES IN SOUTHERN ARIZONA USING GROUND-PENETRATING RADAR

Conventional ground penetrating radar (GPR) surveys typically have a m aximum depth of penetration of 1/2 to 1 m in the basin-fill sediments of the southwestern United States. Although this depth of penetration is too limited for many engineering and environmental surveys, it is o ften suitable for archaeological investigations in this region. We hav e found a center frequency of 500 MHz to be optimum. Radar signals hav ing a center frequency of about 80 MHz produce records with much lower resolution and only slightly greater maximum depth of penetration. Su ccessful GPR surveys have imaged buried plaster and adobe walls, roast ing pits, canals, trash pits, plastered floors, and artifacts such as pot sherds and knives. We have found that GPR is a valuable tool for a rchaeological studies in this area. GPR can provide some of the detail ed survey information that has been provided in the past by extensive excavation, but without the high cost of excavation, without the dange rs of vandalism when artifacts are exposed, and without disturbing sen sitive areas.