First results of subsurface radon monitoring by network of points, operating in the test mode on the south of Sakhalin iseland

Radon monitoring in the world literature is recognized as a promising method for predicting earthquakes. In the last decade on the Kamchatka Peninsula, the prospect of radon method to forecast subduction earthquakes has been quite convincingly demonstrated. The southern part of Sakhalin Island is a region of high seismic risk. The results obtained on Kamchatka give grounds to hope for the detection of precursor anomalies in the radon field (Rn) and for weaker, but also dangerous, small-focus earthquakes on Sakhalin Island. A network consisting of three points for monitoring volume activity of radon (VA Rn) in the air of the subsoil is currently operating in the test mode in the south of Sakhalin Island. In order to better understand the conditions of Rn migration to the surface, seismic survey was performed in the vicinity of the installed radiometers. Volume activity of radon is registered by $\alpha$-radiation using the method of forced convection. The manifestation of weak seismic activity in the south of Kuril-Kamchatka and in the north of the Japanese seismic regions was reflected in the dynamics of the subsurface radon at two points. After testing the equipment and installing stationary points, it is planned to use radon monitoring data as an additional parameter to substantiate conclusions about the seismic hazard of the south of Sakhalin Island.