Geoelectric and magnetic survey at La Libertad archaeological site (San Cayetano County, Buenos Aries Province, Argentina): a transdisciplinary approach

Abstract

Archaeological investigations have been taking place since 2006 regarding 19th century Creole rural settlements in the southeastern portion of Buenos Aires Province. The results of applying two geophysical prospection methods at La Libertad archaeological site, a large livestock ranch in San Cayetano County, are presented. The main objectives were to delimitate possible structures, including moats and tunnel; to detect and explore the most relevant geophysical anomalies; to evaluate the use of two geophysical methods at a reduced scale of analysis (m); and to analyze and discuss the archaeological materials. Using an electrical imaging technique, the electrical resistivity of the subsoil was studied over an area covering most of the site. The resistance anomalies observed may indicate the presence of distinct features such as burrows, roots, brick structures, and archaeological material. Magnetic susceptibility data was registered in some of the electrical profiles. The archaeological materials recovered were bone, glass, ceramic, metal, bricks and one fallenwall, among others, all corresponding to the last quarter of the 19th century and coinciding with the different written sources concerning the La Libertad of Gomila ranch (photographs, letters, memoirs, etc.).