Monitoring of terrestrial gamma radiation exposure in different geological Stress conditions of Uttarakhand Himalayan region, India

Abstract

Terrestrial gamma radiation dose (TGRD) exposure on the earth's surface establishes the linkages with the distribution of radionuclide elements in that particular environmental condition. The rate of variation of the terrestrial gamma radiation in the environment is directly associated with the regional geology and to the elemental concentration of these elements. In this study, Environmental TGRD rates (mSv/h) were measured over the three different geological conditions (Kamal valley, Tona valley and Yamuna valley) with the objective of establishing baseline data on the background radiation. An extensive survey of gamma-ray dose rate is conducted focusing the areas highly suitable for fractures and valley zones. The rocks types in the study regions are basically unconsolidated and moderately structured. The Gamma-ray dose rate at one (1) meter above the ground was measured at 46 points, using a pocket survey dosimeter which. The highest TGRD rate (0.27 mSv/h) is observed (with 35% estimation error) at the location of Rama site in the Kamal valley. Similarly, for Buthothra site of Tons valley it is found to be 0.21 mSv/h with estimation error 37% and at Rekhud site of Yamuna valley it is 0.19 mSv/h with estimation error 36%. The ranges of the gamma dose rate in other sites are also found under the recommended value with normal distribution.