Geothermal Geophysical Study of Mt. Papandayan, Garut District, West Java Indonesia (original) (raw)

Papandayan volcanic complex (1,100 - 2,665 m asl) is dominated by young Quaterary andesitic rocks, showing cones, faults, dome and collapse structures. Extensive alteration of inner and outer volcanic flank with high tempearature fumaroles (80–150 o C), indicates that H2S gases affect on fresh rocks. The gas geothermometry shows 250 o C or higher subsurface temperature, suggesting the low temperatur gas may take place below the older Tegal Alun-Alun volcanics. Magneto-telluric (MT) survey results for the north and north-east slopes of Papandayan indicates resistivity variations of conductive and resistive layers. Low frequency ( 1000 Ohm-m) presumably indicates deep hard rocks, as a part of heat source media.