• MUTHAMILSELVAN A
• Dr.J.SARAVANAVEL

Intrinsic uranium concentration of Crystalline rocks in parts of Salem and Namakal districts of Tamil Nadu were identified with the aid of handheld gamma ray spectrometer. For the identification of uranium distribution in the hard rocks, grab samples of 29 numbers were collected from different rock types such as hornblende biotite gneiss, calc-granulite gneiss, granite, dunite and pyroxenite from the study area. The collected samples were assayed for U, Th and K content using handheld portable Gamma Ray Spectrometer model RS-125 in the laboratory. This instruments wereeffectively utilized to identify the presence of radioactive elements in the rock samples where uranium and Thorium aremeasured in the unit of PPM and potassium is represented in percentage. Total Count readout at a 1x / sec rate in the Survey Mode or variable (1 - 20 sec.) in the Scan Mode of the spectrometer. Among the 29 rock samples, 23 samples wereassayed uranium values between 0.2 ppm to4.9ppm and thorium was assayed very higher concentration which ranges from 8.2 to 51.5 ppm. Potassium was measured in percentage which ranges from 1.2 to 3.4 %. In addition to this, ratio maps of U/K and U/Thwere generated totracethe localization of uranium ore. Distribution of uranium, thorium, potassium, U/K and U/Th ratiovalues were contoured and classified into three classes under GIS environment. In these classification higher concentration of uranium was noticed near Nangavalli, Mecheri and Pakkanadu region which falls along the Koratti shear zone and parallel to the carbonatite trend.

Intrinsic Uranium, Handheld Gamma ray Spectrometer, U/Th and U/K ratio, Salem and Namakkal District, Tamil Nadu

"Intrinsic Uranium Concentration of Crystalline Rocks in Parts of Central Tamil Nadu, India", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.5, Issue 8, page no.1-8, August-2018, Available :http://www.jetir.org/papers/JETIR1808001.pdf

"Intrinsic Uranium Concentration of Crystalline Rocks in Parts of Central Tamil Nadu, India", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.5, Issue 8, page no. pp1-8, August-2018, Available at : http://www.jetir.org/papers/JETIR1808001.pdf