Measuring Complexity of Geophysical Processes: Implications for Earthquake Prediction and Geophysical Prospecting

Last years development of new methods of analysis of so called disordered systems shows that<br>many objects and processes that earlier were considered as completely random reveal clear evidence<br>of having some ordered structure in time and space domain. These new methods (theories of fractals,<br>percolation, nonlinear analysis of time series) allow visualization and quantitative assessment of the<br>level of complexity (orderliness) of these structures, using both theoretical models and experimental<br>data. It seems that seismology, including earthquake prediction research as well as geophysical<br>prospecting can benefit from using the new technique for coping with complexity of these natural<br>phenomena; for example, the measure of complexity can give some new characteristic of a geological<br>formation, change before strong earthquake, etc. In this connection we consider the heterogeneity of<br>geological formations, strain sensitivity of transport processes, nonlinear structures in seismic time<br>series, their relation to the earthquake prediction problem and possibility of anthropic control of<br>seismic process.