Gravity Survey of the Mesoamerican Cuicuilco Archaeological Site, Southern Basin of Mexico

Abstract

The Cuicuilco archaeological site is an early Mesoamerican Preclassic ceremonial and urban center in the Basin of Mexico. The site is characterized by a round-section pyramid and several well-preserved stone structures that were covered by lava flows and tephras by the ~2000 yr old Xitle volcanic eruption. This article presents results from a gravity study to investigate the underground structure. Site gravity anomalies show a gradient trend from southeast to northwest related to the lava flow cover and underlying topographic relief. A semi-circular gravity anomaly high of around 6 to 8 mGals marks the circular main pyramid. The survey also detects two small amplitude anomalies on the eastern side of the pyramid, just north of the access ramp. The main access western ramp does not show any associated gravity anomaly. No other anomalies are observed around the pyramid structure in the surrounding excavated area. The gravity anomaly over the lava field masks any possible anomalies associated with other buried structures likely to be present in the site.