Joint 1D inversion of MT and TEM resistivity data from the Theistareykir high-temperature geothermal area, NE-Iceland and comparison with alteration and temperature logs from boreholes

Abstract

Due to future demands for energy, it is essential to identify and develop new geothermal fields. As a result of this situation, many exploration projects have been carried out. Magnetotelluric (MT) and Transient electromagnetic (TEM) soundings in Theistareykir area were carried out by Iceland Geo-Survey (ISOR). In this study 15 MT and 15 TEM soundings from Theistareykir were used to study the resistivity subsurface structure. Both 1D TEM inversion and MT-TEM joint 1D inversion were performed for each and every sounding site. Two resistivity profiles and a number of iso-resistivity maps were compiled. With the aid of Zstrike, T-strike analysis and alteration mineralogical data from neighbouring boreholes, the resistivity structure and possible heat sources were interpreted.