| Abstract |
Patuha Volcano (West Java, Indonesia) has no record of magmatic or phreatic activities since 1600 AD, but there are abundant hydrothermal surface features that testify to a recent period of volcanic/intrusive activities. Apart from a crater lake and associated gaseous emissions, different types of hydrothermal springs, fumarolic vents, and hydrothermally altered rocks found in the surrounding areas. These manifestations have attracted attention as indicators of potential geothermal energy resources, which led to various exploration efforts. In detail, the thermal springs are comprise of Alun-Alun (ALN), Barutunggul (BRT), Cimanggu (CMG), and Cibuni (CBN). They are located on the northern and eastern sides of the complex. The BRT, CMG and CBN springs are situated at similar elevations and distances from Kawah Putih. The ALN location is higher and closer to the lake. The thermal springs are classified in terms of relative Cl-SO4-HCO3 contents. The Alun-alun spring (ALN) issues chloride-sulfate acid waters (410-952ppm SO4 and 510-699 ppm Cl), and plots in the volcanic water region, close to the lake water (PT). The acid Cibuni spring (CBN) was leak in Cl (<1 ppm) and rich in SO4 (~1200 ppm, calculated from total S), plotted near the SO4 corner in the field of steam heated waters. In contrast, the neutral Cimanggu waters (CMG) are relatively rich in HCO3 (~300 ppm), low in Cl (27-57 ppm) and SO4 (27-57 ppm), and can be classified as ëperipheralí waters. The near neutral Barutunggul waters (BRT) contain Cl (290-587ppm), SO4 (180-519ppm), as well as HCO3 (~400ppm), and plotted in the middle of the diagram. They fall on a line of CMG and PT+ALN, which suggests that the BRT spring represents a mixture of both components. |