Effect of natural radioactivity content in the beach sands along the east coast of Tamil Nadu, India, due to tsunami

摘要

In the aftermath of devastating tsunami, studies were undertaken to assess its impact on the environmental radioactivity profile in the beach sands along the entire east coastal region of Tamil Nadu state (～1000 km) and compared with previously established pretsunami distribution profile. The results of the present study clearly indicate that the radioactivity content of ~(232)Th and ~(238)U in the beach sands registered a steep fall {52% and 41%, respectively), whereas the ~(40)K activity has increased by 26%. This is attributed to the hydrodynamics of tsunami waves, which removed huge quantities of beach minerals that have been built-up over a few decades. The individual activity content of the three primordial radionuclides, total activity content, comparison between pre- and post-tsunami data for all the 32 sites, and their statistical analyses are covered in the paper.