Title of research project: Study of the symptoms of the instability in solid earth including geological disasters and ecological catastrophes

Reference number of the grant: INTAS-93-457

Period of performance: 1994 to 1998

Project Coordinator: Prof. J.-L. Le Mouel (IPGP, France)

Principal Investigator: Dr. I. Rotwain


General direction of the research includes: - representation of lithosphere as non-linear hierarchical dissipative system; - reconstruction of scenarios of critical transitions in the lithosphere, i.e. earthquakes and other geological disasters, on a basis of mathematical modeling and available observations; - design of probabilistic methodology to evaluate statistical significance of developed hypotheses (e.g. on hypothetical precursors to a disaster).

Following types of models were investigated: - lattice models of interacting elements, in particular, models based on renormalization; - probabilistic models of self-exciting processes; - models of a system of blocks and faults with realistic geometry.

Phenomenological study covered Lesser Antilles, Alps, Pyrenees and microplates in the North-Eastern Russia. Comparison of models and phenomenology was used to search for scenarios of instability in the lithosphere at different spatial, temporal and energy scales. The data on seismicity, slow crustal deformations and electromagnetic fields were analyzed. General methods of modern non-linear dynamics which are applicable to a vast variety of phenomena might help in understanding and eventually in prediction of geological disasters such as earthquakes, volcanic eruptions, etc. We tried to overcome an existing gap between state- of-the-art modeling and actual phenomenology of relevant geophysical fields. Specific tasks included localization of instability symptoms, their integration into scenarios, and monitoring of stress-field. User-friendly software for seismological data analysis was created.