Radon studies over Main Boundary Thrust near Dehradun (India)

A detailed radon survey has been carried out over the Main Boundary Thrust near Dehradun, Uttar Pradesh. Radon measurements were performed in the grid pattern using radon emanometry and an LR-115 type II plastic track detector. The radon concentration was found to vary from 0.04 ± 0.01 to 0.58±0.04 pCi/ml and 0.06 ± 0.006 to 1.59±0.09 pCi/ml, by the radon emanometry and track detector techniques, respectively. Both the techniques are found to be suitable. However, the track detector technique is more efficient than radon emanometry. The study of contour maps of radon shows that the radon distribution pattern is almost identical in both cases. The comparatively high values of radon emission may be explained as due to the active nature of the Main Boundary Thrust. (author)