Physical and mathematical models of the occurrence of earthquake fluid anomalies in hydrogeochemical fields of seismically active areas

Abstract

Comprehensive monitoring of seismic activity over the last 40 years at the special Almaty Forecasting Polygon (AFP) in Kazakhstan has demonstrated that the physical, mathematical and chemical mechanisms of fluid anomalies in the groundwater regime are quite convincingly substantiated by the example of tracking many strong earthquakes. The purpose of this research – to analyse the system “water-rock-gas”, in particular the genetic features of the manifestation of exotic unstable time anomalies. The research methods used in this work include systematic data analysis, and their interpretation and evaluation based on dilatant-diffuse (DD) and avalanche unstable fracturing (AUF) models. The first results of research of such anomalies preceding major earthquakes in the main earthquake-prone areas of the USSR, China, and Japan were manifested in sudden increases or decreases in the concentration of a wide range of components of the ion-salt composition of groundwater and its gas components: HCO–3, CO2–3, Cl, SO2–4, Ca2+, Mg2+, Na, K+, pH, He, Rn, CO2, CH4, H2, and Hg. They varied in the time interval from hours, days and the first weeks and months before the earthquake. In addition, the changes were explained by theoretically generally accepted models of DD or AUF earthquake occurrence. The proposed studies demonstrate and state the main genetic features of the manifestation of these exotic unstable temporal anomalies in the hydrogeochemical system “water-rock-gas”. Based on the results of long-term studies of hydrogeochemical and hydrogeodynamic precursors in the fluid regime of the Earth’s crust in Kazakhstan, Kyrgyzstan, Uzbekistan and Xinjiang Uygur Autonomous Region of People’s Republic of China, a more convincing physical and chemical model of the development of fluid anomalies in the process of preparation of strong earthquakes is proposed. The practical significance lies in the following aspects: the development of accurate models can help in predicting possible earthquakes based on fluid anomalies in hydrogeochemical fields; using physico-mathematical models can help in establishing systems for monitoring seismic activity based on the analysis of hydrogeochemical parameters; the research can help in assessing the risks associated with earthquakes in seismically active areas and in better understanding of the physical processes occurring in hydrogeochemical fields; and the research can help in assessing the risks associated with earthquakes in seismicallyactive areas and in better understanding the physical processes occurring in hydrogeochemical fields