One- and two-dimensional interpretation of dc-resistivity data from the Berlín geothermal field, El Salvador

Abstract

The results of the interpretation of 50 resistivity soundings carried out in the Berlín geothermal field delineate an extensive geothermal field of 12 km2 at 250 m below sea level. The field is characterized by a low-resistivity cap which is underlain by a high-resistivity core where temperatures exceed 230°C, providing there is an equilibrium between temperature and alteration. The upflow zone is within the caldera close to well TR-5. This is supported by the highest measured temperatures and highest elevation of the high-resistivity core. The existence of a high-resistivity core suggests a fresh water system in the uppermost part of the reservoir, or at least at the depths where resistivity data is dependable.