A Portable Gamma Ray Spectrometer is a crucial tool in geological studies for measuring natural radioactivity from subsurface formations. It specifically detects gamma radiation from elements like potassium, thorium, and uranium. These elements are key indicators of rock types and play a significant role in mineral exploration to identify valuable deposits. The data obtained from gamma-ray spectrometry, often used in conjunction with Gamma Scanning Equipment, is vital for stratigraphic correlation, helping geologists understand geological formations across different well sites. This non-destructive method is extensively used in both mining and energy sectors.