A combined approach of thermal remote sensing and ground-based measurements for radioactive mineral exploration at the Eastern Coast of India

Abstract

This study investigates the potential of thermal remote sensing for delineating radioactive mineral deposits by examining the relationship between land surface temperature and the presence of these minerals. The underlying hypothesis is that radioactive decay, while typically generating heat, can contribute to detectable thermal anomalies in areas with significant concentrations of radioactive minerals. Utilizing Landsat 8 Operational Land Imager, Land Surface Temperature (LST) patterns are analysed in the coastal region, Podampata, Odisha, eastern coast of India and compared with occurrences of radioactive minerals. The Land Surface Temperature in the study area ranges from 19.4 °C to 28.34 °C. Preliminary findings indicate a positive correlation between LST and the presence of radioactive minerals such as monazite and zircon, suggesting that areas with higher LST represent potential targets for mineral exploration. However, the contribution of radioactive decay heat to the observed LST anomalies needs further investigation and validation through ground-based measurements of radioactivity, Thorium (Th), Uranium (U) and Rare Earth Element (REE) enrichment and detailed thermal modeling. The dose rate ranges from 65 to 240 µR/h, with the highest concentrations of thorium and uranium recorded at 39.61 ppm and 16.28 ppm, respectively. The presence of radioactive heavy minerals such as monazite and zircon and other heavy minerals such as ilmenite and rutile are confirmed from this study. Enrichment of light REE compared to heavy REE along with absorption dips around 1 μm, indicates the presence of Sm³⁺, commonly associated with monazite. Finally, integration of results from remotely sensed data and field data was performed to obtain a comprehensive solution for delineation of regions enriched with radioactive minerals. This research highlights the potential of thermal remote sensing as a preliminary tool for the identification of regions suitable for the exploration of radioactive minerals.