Geodynamical impacts on the water level Variations in boreholes

Abstract

It is known that variations of water level represents itself an integrated response of aquifer to different periodic as well as non periodic influences, including earthquake related strain generation in the earth crust. Quantitative analysis of impacts of separate components in observed integral dynamics remains one of the main geophysical problems. It is especially important for non periodic processes related to the earthquake generation, taking into account their possible prognostic value. In the present study the dynamical complexity of water level variations has been analyzed. Dependence of dynamics on the presence of periodic components in considered data records (time series) was investigated. Modern tools of time series analysis have been used. We present results of the analysis of the data of observations by a special program. The results illustrate that correlative dependence between tidal variations and water level changes is breached several days before the earthquake, both in the amplitude and the frequency spectrum.