Geochemical Fluids Assessment of Gunung Endut Geothermal Area, Banten Province, Indonesia

Abstract

Geochemical assessment was completed in Gunung Endut geothermal area to determine fluid characteristics discharging from their natural surface manifestations. Gunung Endut geothermal area is centralised in the western part of the region. Three surface manifestations located in Desa Handeuleum, Cikawah and Gajrug appears along the apparent structural (fault) line. Diluted chloride-carbonate water belongs to partially equilibrated group may indicate mixing between chloride water and groundwater. Quartz and Na-K geothermometer indicated reservoir temperature of 107-127 °C and 111-132 °C respectively. Geoindicators of Cl/B indicated that there are two separate reservoirs in the sub-surface. Geoindicators of Na/K and Na/Ca revealed that all the manifestations lie in the outflow zone of Gunung Endut geothermal area.