Regional gravity of los humeros volcanic area

Abstract

A negative gravity anomaly has been obtained on the eastern end of the Transmexican Neovolcanic Axis. Tectonically the anomaly appears to correspond to a sinking in which a series of volcanic episodes have taken place; the area is considered a potentially producing geothermal field. The area is limited to the North .by the lithogical complex of Teziutlán, to the South by the Tepeyehualco plains, to the West by the Sierra Madre Oriental and to the East by the Pico de Orizaba-Cofre de Perofo range. The study includes the gravimetric map of complete Bouguer anomalies, the maps resulting from the regional-residual separation, and a two-dimensional model through the central portion of Los Humeros caldera which contains a central, positive anomaly apparently corresponding to a massive central plug. In addition to a schematic discussion of the evolution of the volcanic area, the existence is proposed of a caldera located between Los Humeros Caldera and Cofre de Perote mountain, which is completely filled by volcanic materials.