An integrated study to detect geothermal anomalies based on Landsat 8, Geological, and Geophysical data sets in Southeast Pakistan

Geothermal resource exploration has grown in importance globally as a research hotspot due to the depletion of conventional fossil fuel reserves and green energy initiatives. This research's prime objective is to explore the geothermal potential, primarily focused on the Paleocene rock geothermal systems in Southeast Pakistan. Globally, the use of remote sensing for geothermal anomaly detection has gained much attention recently due to the increased focus on green energy. This study aimed to identify regions with geothermal anomalies using land surface temperature (LST) data, a geospatial dataset to develop geological mapping, and geophysical well logs analysis to compute heat production and petrophysical analysis. An overview of geo-pressurized systems and geothermal resources’ location in Southeast Pakistan has been provided to get an idea of the geothermal target in this region. The LST values were quantitatively classified into five categories: very high, high, medium, low, and very low, and LST results indicate that the data cluster lies in 20 %, 54 %, 4 %, 3 %, and 19 %, respectively. Normalized difference vegetation index results showed that 96 % of the study area lies in bare soil to mixed surface, and only 4 % of the region lies in full vegetation. Petrophysics results indicate that the Ranikot Formation has very good effective porosity ranges of 20–24 % in the studied wells, suggesting a potential candidate for enhanced geothermal systems (EGS). Basin modeling was performed to delineate subsurface heat flow (109–113 mW/m²), temperature (60–150 °C), and effective porosity (22–24 %) distribution mapping. The concentration number (CN) model and log-log plots techniques were employed to map gamma-ray and heat production values to separate the geothermal anomaly and spatial correlation from its background. Emerging advancements in technologies such as EGS for exploiting geothermal energy and reducing exploration risk are crucial economically in geothermal reservoirs. These innovations have attracted researchers to explore the potential to utilize geothermal energy significantly. Still, their successful implementation principally relies on an in-depth understanding of the local geological conditions of the basin.