Heat flow map and geothermal resources in Mexico

Abstract

Heat flow maps are a powerful tool for regional exploration of geothermal resources. Mexico is one of the main producers ofgeothermal energy and the search for undiscovered resources at a regional level should be based on heat flow values. Here, we present a heat flow map at 1:4,000,000 scale, produced with heat flow data compiled from open data bases and previously unpub-lished data. The compiled heat flow data includes bottom hole temperature, temperature logs, transient temperature measurements and measured temperature logs. The new data were calculated from temperature gradient information and estimating a mean con-ductivity value characteristic for the type of rock present in the stratigraphic column or assigning the mean conductivity value for the crust. Geothermal gradient and the thermal resistivity (inverse thermal conductivity) were plotted and heat flow was calculatedusing the Bullard method. The map covers the whole continental territory of Mexico and shows that most of the country has valueshigher than the world average. The highest heat flow values are concentrated in two provinces: the Gulf of California extensionalprovince and the Trans-Mexican Volcanic Belt.