A new method for studying the transport of gamma photons in various geological materials by combining the SSNTD technique with Monte Carlo simulations

Uranium and thorium contents in different geological samples were determine d by using CR-39 and LR-115 type II solid-state nuclear track detectors (SS NTD) and by calculating the probabilities for a-particles emitted by the ur anium and thorium series to reach and be registered on the SSNTD films. A n ew method has been developed based on the calculation of the self-absorptio n and transmission coefficients of the gamma photons emitted by the uranium or thorium families and by the potassium 40 (K-40) isotope for evaluating the gamma dose rate in the samples. Moreover, the transport of gamma photon s across parallelepipedic blocks of the geological materials was investigat ed. Using the results of these studies, the gamma dose rates in the atmosph ere of different geological deposits were evaluated. (C) 2001 Elsevier Scie nce Ltd. All rights reserved.