ESTIMATION OF THE CURIE ISOTHERM DEPTH IN A PART OF THE AZUFRAL VOLCANO INFLUENCE ZONE BASED ON GEOMAGNETIC DATA

Abstract

In this study the depth of the Curie isotherm was estimated, based on the spectral analysis of geomagnetic anomaly data from one part of the Azufral volcano infuence zone, covering an area of about 450 km2. The obtained depth showed a range between 2.3 and 14.2 km with an average of 3.7 km. Based on the obtained depths, the geothermal gradient and the heat fow of the study area were estimated, with an average of 157 °C/km and 204 mW/m2, respectively. The results indicate that the isotherm is not a horizontal surface and there is an inverse relationship between the depth of the Curie isotherm and the values of geothermal gradient and heat fow. There are not direct measurements of geothermal gradient in the area, so these data constitute a contribution to the geothermal resources exploration in the Azufral volcano infuence zone.