Chemical and physical characteristic of patuha geothermal field manifestations, West Java, Indonesia

Patuha geothermal field is one of the volcano-hosted vapor-dominated geothermal systems located in West Java, Indonesia, operated by PT. Geo Dipa Energi with an installed capacity of 55 MW. Although it has been operated since 2014, it is necessary to have geochemical studies to monitor and determine the field conditions after production. Patuha field has some types of surface manifestation, such as hot spring, warm spring, cold spring, fumarole, and mud pool. The focus of this study is to determine physical and chemical characteristics, including temperature, pH, TDS, major anions contents (Cl, SO₄, HCO₃), and major cations contents (Na, K, Ca, Mg) at nine manifestations comprise hot springs, warm springs, and fumaroles. The temperature range is in between 36 – 93 °C, and the pH value range of 0.78 – 6.77. Based on the physical and chemical data, we can recognize the type of water, the equilibrated waters, and the processes that may occur in the water. Based on the anions content, there are several water types of hot water manifestations, classified into chloride water, sulfate water, bicarbonate water, and chloride-sulfate-bicarbonate water. Based on the cations content, all of these waters are immature water.