Geomagnetic Investigation to Delineate Heat Source of Geothermal Potential in Jambi Sub-Basin

Pandan Sejahtera Village, Geragai, East Tanjung Jabung, Jambi, is an object study area to make observations, because the discovery of geothermal manifestations in the form of hot springs with a temperature of about 60 degrees Celcius. The study area is located in back-arc basin which is far away from subduction zone and active volcanoes. In geothermal exploration, Geomagnetic Method used to identify the type of rock that is the source of heat. Interpretation of geomagnetic data is done by using Reduce to Pole and Upward Continuation as filters. In order to calculate those filters, Fast Fourier Transform (FFT) was applied to the geomagnetic data by using Oasis Montaj software. Based on the Upward Continuation filter results the Author interpret that distribution of shallow and deep anomalous zone are respectively associated with residual and regional anomaly magnetic. Deep anomaly in the East - Northeast direction is interpreted to be associated with a heat source because it has a low magnetic anomaly value owned by demagnetized rocks due to high temperatures.