The San Marcos Pueblo Archaeological Site: A Review and Update of Ongoing Work by the Summer of Applied Geophysical Experience (SAGE)
Abstract:The San Marcos Pueblo, one of the largest and most important cities of the pre-European Southwest, has long been a place of curiosity for archaeologists and geophysicists alike. Despite numerous archaeological investigations, primarily test excavations and surface surveys carried out at San Marcos from the early 1900s to the present, the site retains pottery sherds scattered along the surface from when it was first occupied in the thirteenth century to its abandonment during the Pueblo Revolt of 1680. Geophysical investigations have identified locations of kivas (ceremonial pits), middens (trash heaps), room blocks and possible metallurgy activity in the area. The site is located south of Santa Fe, NM and to the east of the Cerrillos Hills, a source for lead ore and turquoise.
The students of SAGE have studied the San Marcos Pueblo for the past 11 years, and produced a map of the northeastern portion of the Pueblo colloquially called ‘El Mapa Grande.’ Ground penetrating radar (GPR), magnetics, and electromagnetic (EM) data were acquired on 30mx30m grids and seismic refraction data on various profiles throughout El Mapa Grande. During the 2014 field season new GPR data were acquired on two grids, magnetics data on one, and multiple grids were resurveyed with magnetics and EM to enhance resolution. The most recent GPR data extend coverage of two large anomalies that are part of linear EW-trending structures previously identified and consistent with a possible block wall or midden. Low GPR scatter and circular magnetic lows define several kivas. A target area in the NE of El Mapa Grande was thought to be related to metallurgic activity. Analysis of previous seismic data did not resolve any subsurface features corresponding to a metallurgy operation, but detected the magnetically-chaotic Ancha formation. Comparison with magnetic profile data support the interpretation that this anomaly is caused by a sub-crop of the Ancha Formation.