K-40 RADIOACTIVITY IN UNDERGROUND MINERAL WATERS OF SEISMOACTIVE ZONE

The gamma radiometry technique was used for the detection of 40K natural radionuclide in thermal mineral waters from the Tashkent geodynamic polygon where the powerful earthquake (1981 y) took place. For the study of the change in 40K radioactivity connected with the process of the occurrence of powerful earthquake, the method of regular observation has been applied. The detection of 40K radioactivity during 610 days showed that it changed strongly before (~ 3.5 d) powerful earthquake processing most strong property of the earthquake’s harbinger. The 40K radioactivity has higher value 33-45 hours until the earthquake. After the earthquake during 2-3 days the value of 40K radioactivity was decreased till the daily average level.