Resistivity Methods Applied to Geothermal Exploration in the Philippines

Abstract

A number of resistivity methods have been used in the search for geothermal resources in the Philippines. methods are reviewed, using examples taken from surveys conducted in Tongonan, Southern Negros, Biliran, Mambucal, Davao and Bacon-Manito. Experience acquired from interpreting the substantial amount of resistivity data collected using Schlumtraverses, vertical electrical soundi n g s, and the dipole-dipole technique, suggests that maximum information can be gained from an in - tegrated interpretation of these data. Di pol dipole pseudo-sections should be modelled using soundings to define the near-surface layers. Both low and high resistivity anomalies delineated by traversing surveys should be checked by soundings to determine the vertical resistivity structure. Sounding sections are also useful to assist hydrological modelling in cases where the main resistivity anomalies are associated with extensive shallow outflows of geothermal fluid.