DESCRIPTION AND CLASSIFICATION OF SEISMOGENETIC TECTONICS
Ma Zongjin (Center for Analysis and Prediction, State Seismological Bureau)
Seismogenetic tectonic environment is one of the fundamental factors to study seismic source mechanics and earthquake causes. In principle, the cause of earthquakes can be divided into two major categories: individual and group earthquake causes. For group earthquakes there are three basic kinds of tectonic conditions:(subduction zone) tongue-like plate tectonics; (oceanic ridge) fracture offset tectonics; and (continental crust) grouped plate tectonics. Tectonic environments of the individual earthquake origin can be classified as follows I, T, X, X', Q and A types, based on the plane combinations of fractures prior to mainshocks in focal regions. In this study, the geometrical elements for the above-mentioned two major categories of the earthquake origin are described and discussed.