The gravity method is broadly used in analyzing potential geothermal studies. The method can be used for determining potential areas, reservoir locations, and geological structure investigation. In this paper, satellite gravity data was applied for better understand the geological conditions connected with the geothermal system of Bur Ni Geureudong geothermal field, Bener Meriah District, Aceh, Indonesia. Open access Free Air anomaly data were provided by satellite geodesy information with 1 minute-grid. The data were reduced to obtain Bouguer anomaly distribution in the study area. Tilt derivative (TDR) technique was applied to Bouguer anomaly to enhance linear trends of geological structures. The aim of this analytical technique is able to clearly display faults correlated with geothermal manifestations around the Bur Ni Geureudong geothermal field. The complete Bouguer anomaly range of 20 mGal up to 170 mGal covers Bur Ni Geureudong volcano complex. A low Bouguer anomaly is located in all summits of volcanoes that are included in Bur Ni Geureudong Volcano Complex; those are summits of Bur Geureudong volcano, Bur Ni Telong Volcano, Pepanji Mountain, and Salah Nama Mountain. The low Bouguer anomaly is associated with the andesitic flow and volcanic ashes. The higher Bouguer Anomaly is reflected in high-density basement rock in the west of Geureudong Volcano. Tilt derivative (TDR) shows geological structures more detail, particularly, the tilt derivative (TDR) clearly detects two fault structures over the study area presented by a tilt value of zero. The results will be useful as basic information in exploration study of Bur Ni Geureudong geothermal field.

Bur Ni Geureudong is one of geothermal areas that potentially to be developed for geothermal power plant in Aceh Province, Indonesia. Prior to the development, detail investigation based on geological, geophysical and geochemical methods are needed for estimating its potential. However, this site is located in a mountainous area with dense forests that are difficult to reach and research of geothermal exploration in site is still very poor considering its promising potential. So that the use of remote sensing method is very suitable to be done to investigate geothermal potential in these remote areas. For reconnaissance survey, Land Surface Temperature (LST) mapping using Landsat 8 OLI/TIRS (Operational Land Imager/Thermal Infrared Sensor) image data was conducted to investigate the geothermal potential in the area. Radiometric correction, Normalized Difference Vegetation Index (NDVI) mapping and emissivity calculations were performed to obtain the LST map. Results show temperatures in the area ranged 17⁰C to 40⁰C, the area with high surface temperatures are caused by geothermal activities. NDVI map also shows an agreement with the high surface temperature region and they are mostly indicated by occurrence of vegetation stress. Keywords: Bur Ni Geureudong geothermal field, Landsat 8 OLI/TIRS., land surface temperature, Thermal remote sensing

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