A study of variation in soil gas concentration associated with earthquakes near Indo-Burma Subduction zone

Abstract

Background: In the recent past, several efforts have been made by a number of researchers to measure anomalous emanations of geo-gases in seismic prone regions of the world and radon has been the most preferred geo-gas as possible earthquake precursor since it is easily detectable. Results: In the present investigation, continuous measurements of radon concentration at 80 cm inside the soil has been carried out at Chite Fault (23.73°N, 92.73°E), Aizawl, Mizoram situated in the seismic zone V in North Eastern part of India near Indo-Burma subduction zone, using LR-115 Type-II nuclear track detectors manufactured by Kodak Pathe, France. During the investigation period, the radon concentration varied from 163.27 Bq/m 3 to 2557.82 Bq/m 3 with an average and standard deviation of 1116.15 Bq/m 3 and 591.76 Bq/m 3 respectively. Conclusion: Certain anomalies observed in radon concentration have been correlated to the earthquakes within the range of magnitudes 4.7 ≤ M ≤ 5.5, while some other anomalies are due to the influence of meteorological parameters.