We assess geothermal resources from our understanding of the structure and the dynamics of geothermal reservoirs and
hydrothermal systems in the south of Bandung. The co-existence of a large variety of intense surface manifestations like geysers, hot-steaming grounds, hot water pools, and active volcanoes suggest an intimate coupling between volcanic, tectonic and hydrothermal processes in this area. We deployed a geophysical network starting with a network of 30 seismic stations including high-dynamic broadband Güralp and Trillium sensors (0.008 - 100 Hz) and 4 short-period (1 Hz) sensors from October 2012 to December 2013. We extended the network in June 2013 with 16 short-period seismometers. Finally, we deployed a geodetic
network including a continuously recording gravity meter, a GPS station and tilt-meters. In this paper we describe the set-up of the seismic and geodetic networks and we discuss first observations and results. The earthquakes locations were first estimated using a non-linear algorithm, and revealed at least 3 seismic clusters. We perform joint inversion of hypocenters and VP velocity 1D and 3D tomography. We discuss the resulting seismic Vp structure and the seismic activity pattern within the area and relate the structure to the distribution of hydrothermal systems. We aim at searching possible structural and dynamical links between different hydrothermal systems. In addition, we discuss possible dynamical implications of those volcanic systems from temporal variations of inferred parameters. The integration of those results allows us to achieve a better understanding of the structures and the dynamics of those geothermal reservoirs. This approach contributes to the sustainable and optimal exploitation of the geothermal
resource in Indonesia.