Geophysical Location, Identification, And Characterization Of Archaeological Structures Of The Jornada Mogollon People At The Three Rivers National Petroglyph, New Mexico

We present preliminary results of an ongoing study regarding the application of shallow geophysical methods to archeological sites using a unique combination of geophysical techniques. This approach adds precision, greater spatial resolution, and time efficiency. In 1976 a group of archaeologists discovered and reconstructed prehistoric structures at the Three Rivers National Petroglyph Site, New Mexico. The area is covered by dense vegetation and, moreover, it is often occupied by cattle and tunnel-digging, den-building mammals, which destroy both surface and subsurface features that could indicate centers of past human activity. The 1976 excavations successfully made use of magnetometry to help locate structures of interest. In the 30 years that<br>followed no further geophysical investigations were conducted, although periodic mapping of surface features and excavations continued. Between December 2005 and December 2006, a new set of geophysical campaigns were carried out at the site, in order to locate new structures. The surveys included ground conductivity, magnetometry (including gradiometry), and ground penetrating radar (GPR). We first used conductivity and magnetic gradiometry to delineate anomalies that could represent structures, followed by GPR. As of October 2006, three areas have been targeted as suspicious, and one of them represents an adobe structure that is currently being excavated. Further reconnaissance studies were carried out throughout December 2006.