1. Department of Anthropology and Geography, Colorado State University, Fort Collins, CO 80523
2. Center for Research in Archaeogeophysics and Geoarchaeology (CRAG), Colorado State University, Fort Collins, CO 80523
3. Department of Earth Sciences, University of Memphis, Memphis, TN 38152
4. Emeritus, Department of Physics and Astronomy, Denison University, Granville, OH 43023