Evolution of Interpretated Geophysical Reservoir of Berlin Geothermal field, El Salvador

Abstract

A resistivity core under a conductive cap, based on the 2D Schlumberger analysis, was delineate as the first propose in 1996, for the reservoir of Berlin geothermal field (BGF), from geophysical point of view. A dense hypocenters cloud registered by the local seismic network, was useful for estimate the extension of the production zone, as well as the heat source and the upflow zone in 2001. A 3D of MT resistivity model, calibrated with temperature and mineralogy of the geothermal wells, in 2008, indicate that the producer reservoir corresponds to a resistivity range of 50 – 90 Ohm- m, inside the resistive dome. The main up flow zone was located around the TR4-TR5 area. New MT resistivity studies carried out in 2010 and 2012 in the southern part indicate a possible extension of the actual reservoir toward the west and southwest of the production zone. A new drilling program focus in this area will confirm the possible extension of the producer reservoir.