Comparative study of seismic surveillance on radon in active and non-active tectonic zone of West Bengal, India

Study of radon behaviour in soil or groundwater provides important information in case of seismic activity within the earth’s crust. In a previous work, we have tried to correlate the occurrence of radon concentration anomalies in soil with incidents of earthquakes within the distance of 1000 km from the experimental site. The experiment was performed at Kolkata, West Bengal, India (22.53°N, 88.4°E) which is not located in an active fault zone. In extension of our study we have performed simultaneous measurement of radon in an active fault zone at Jalpaiguri (26.53°N, 88.76°E), West Bengal, India as well as in Kolkata – a non-active fault zone. The variation of radon concentration in soil gas was measured by SSNTDs [Solid State Nuclear Track-etch Detector(s)]. Interesting features of an anomalous fluctuation in radon concentration in both the seismic as well as non-seismic zones prior to any particular earthquake is reported.