North American Database of Archaeological Geophysics
North American Database of Archaeological Geophysics
Abstract/Summary:
Project Name: Effigy Mounds, IA (3);
Reference: De Vore S.L. (1999). Investigations at Effigy Mounds National Monument during the 1999 "Recent Advances in Archeological Prospection Techniques" Workshop, May 10-14, 1999. Cultural Resources and National Register Program Services, Intermountain Support Office, Santa Fe, New Mexico. Submitted to Effigy Mounds National Monument, Harpers Ferry, Iowa.
The National Park Service's 1999 workshop Recent Advances in Archeological Prospection Techniques was held at Effigy Mounds National Monument in northeast Iowa during the week of May 10-14. The park was selected as part of an ongoing mound study being conducted by archeologists at the Midwest Archeological Center (Lincoln, Nebraska) and to celebrate the park's 50th anniversary as a National Monument.
Magnetic gradient, resistance, soil conductivity, and magnetic susceptibility (inphase EM data) were collected at the conical mound (Mound 45) during the workshop. This report presented the results of the author's geophysical investigations at Mound 45. The resistance, especially with the multiple depth investigations with the multiplexer and three probe separation provided detailed data on the interior construction of Mound 45. While the other techniques provided data on the physical properties of the mound, with the exception of the inphase EM38 data, the resistance layer data provided an exceptional view of mound's internal makeup and integrity. Mound research at Effigy Mounds National Monument should include geophysical techniques in the investigations of mound construction. Geophysical investigations, coupled with the analysis of historic aerial photographs, should be utilized to identify the positions of previously removed mounds. Overall, the various techniques used during the workshop worked well at Effigy Mounds National Monument. This would suggest that such techniques could be applied to other archeological investigations in the northeast corner of Iowa as well as in the adjoining areas in Illinois, Minnesota, and Wisconsin.