Structural Traits of Cuitzeo Lake, Central Mexico, and Areas of Geothermal Potential

Abstract

Cuitzeo Lake, in the central part of the Trans Mexican Volcanic Belt, is in an extensional region associated with the Cuitzeo graben, where magmatic ascent appears to provide the heat sources for the surface, geothermal manifestations. A profuse distribution of andesitic rocks is observed throughout the study area of 50×50 km2. Gravity and magnetic field 3D inversions are calculated to obtain density and magnetic susceptibility distributions to 7000 m depth, from which we analyze N-S and E-W cross-sections and obtain density and magnetic susceptibility geosurfaces that help characterize anomaly areas of interest. We use satellite-derived gravity and magnetic data in our evaluation, owing to their high-resolution characteristics and uniform coverage of the study area. Analysis initiates with the San Agustín del Maíz region (SAM), exhibiting surface geothermal manifestations, to characterize its density and susceptibility characteristics, then the analysis is extended to the whole study area. Several outcropping, low magnetic susceptibility regions, like the one associated with SAM, are suggested as potential geothermal targets. Density geosurfaces point to two volumes where magmatic material may intrude, coinciding with active geologic faults. The analysis presented here can be extended to neighboring regions in the Cuitzeo Lake area and may constitute a fast, unexpensive exploration methodology in similar geothermal districts.