USE OF NUCLEAR PHOTOEMULSIONS TO INVESTIGATE THE SPITAK EARTHQUAKE AFTERSHOCKS

The radon and thoron emanation in soil gases in the epicentral zone of the Spitak earthquake of 7 December 1988 was estimated by the use of nuclear photoemulsions. For measurements of the emanation flow, the st ationary observation points of the Laboratory of Seismogeochemistry of the Institute of Geological Sciences were chosen. The maximum flow wa s detected in the observation point near the village of Saralandzh. He re, the obtained value exceeded by 10.1 times the average level in the Spitak region (the observation point in the town of Spitak). The flow in the north-west wing of the Spitak break was considerably less and exceeded the average value by only 2.1 and 1.5 times (Gegasar and Nalb and villages). A comparative analysis of our data with those obtained in the same observation points by means of the atmogeochemical method shows rather good agreement between the experimental results. The join t application of these two methods allows representation of the geodyn amics of the region and prediction of earthquakes.