Structural map of Sulawesi derives from gravity data and its implications for geothermal systems

Gravity satellites are one of the alternatives to conducting preliminary surveys because the cost
of exploring a large area using conventional gravity methods is very expensive and takes a lot of time.
Therefore, this study on Sulawesi Island uses a gravity satellite to identify fault contact boundaries. The
methodology in this study consists of several steps, starting with a literature study, data collection through
ICGEM, and then processing and analysis by compiling the gravity anomaly with the Sulawesi regional
geological structure map, further interpreted using the classification of rock density variations from a
geological perspective. The regional gravity anomaly values for Sulawesi Island and its surroundings range
from -270.9 mgal to 320.8 mgal, averaging 78.99 mgal. High anomalies are estimated to be between 180
mgal and 360 mgal, dominated by land with a lithology predominance of igneous rocks, while low anomaly
areas are identified in the Batui thrust subduction zone. This study concludes that the convergence of high
and low gravity anomalies characterizes the fault contact boundary in the study area. This has implications
for the geothermal system on Sulawesi Island, which has a significant impact as a medium for the release of
hot fluids from the subsurface.