Short-term variations of radioisotopic parameters of water of the Earth crust fractures and their connection with earthquake prediction

Results of studies of short-time (daily and weekly) variations of the He4, Rn222 content and the U234/U238 ratio in thermal waters of sources of the Kirghiz mountain range, the North Tien Shan seismic zone, are described. The applied sampling procedure provides root mean square errors not exceeding 5 per cent for the He and Rn content and 20-30 per cent for Ra and U content for the following minimum values of studied parameters: 2-4x10-3 per cent for He, 1-1.5x10-9 Ku/l for Rn, 10-13 Ku/l for Ra and 10-7 g/l for U. Results of these observations are plotted on the graphs of time variations of the above-mentioned parameters. Their analysis enables to draw the following conclusions: at periods prior to earthquakes, even in case when the area of the preparation of the earthquake does not spacially coincides with the region of the outflow of sources of fault waters the latter can display the observable general increase and short-time changes of the content of He, Rn and sometimes of Ra which are more frequent and of wider amplitude and which are not influenced by underground waters. They are probably conditioned by the activization of tectonic processes within a seismic zone or within a big fault. The necessity of regular observations of the He and Rn content of waters of sources in tectonically active zones is stressed