Integrated Geoscience Data to Identify Heat Source Beneath Umeh Volcanic Complex in Tompaso Geothermal Field

Abstract

Integrated geoscience data evaluation is needed to determine the location of the heat source in the Tompaso Geothermal Field. The location of the heat source in the Tompaso Geothermal Field should be known to update the conceptual model. The updated conceptual model can be used as a reference in development plans of Tompaso Geothermal Field. Therefore, through integrated geoscience data evaluation such as geological settings, remote sensing data, resistivity and gravity data, fluid chemistry data, and temperature measurements data from wells are expected to determine the presence of the heat sources, especially beneath Umeh Volcanic Complex (UVC) in the Tompaso Geothermal Field. Based on geological and remote sensing data, the location of heat sources of Tompaso Geothermal Field are predicted beneath Sempu Volcanic Complex (SVC) and Umeh Volcanic Complex (UVC). SVC is related to recent volcanic activity while UVC is related to “monogenetic” volcanism. The gravity data beneath SVC showed high gravity anomaly contrasts than its surrounding areas, while high gravity anomaly beneath UVC has lower contrast than SVC. However, chemical fluid analysis from thermal manifestations and temperature from the wells indicated the presence of heat source beneath UVC.