NATURAL RADIOACTIVITY CONTENT OF THE LIMESTONE AND SANDSTONE ROCK SAMPLES IN THE CHIATURA REGION

(SOUTH CAUCASUS, GEORGIA)

Abstract

There are presented the results of the first conducted research of the natural gamma-radioactivity of limestone and sandstone rock samples from the Chiatura region, West Georgia. The study was carried out using a Canberra GC2020 germanium gamma-spectrometer. Twenty-one natural and one technogenic gamma-emitted radionuclides were identified in the studied samples. The activity concentration of the identified radionuclides was determined. The radium equivalent activity ranges from 19.2 Bq/kg to 91.7 Bq/kg with an average of 37.0 Bq/kg for limestone samples and from 32.9 Bq/kg to 374 Bq/kg with an average of 133 Bq/kg for sandstone samples. The absorbed dose rate ranges from 8.96 nGy/h to 42.6 nGy/h (an average of 17.3 nGy/h) for limestone samples, and from 16.0 nGy/h to 176 nGy/h (and average of 64.4 nGy.h) for sandstone samples. There were calculated also the external hazard index and the internal hazard index. The data obtained were compared with literature data. The hazard indices were found to be within safety limits.