Аннотация:The results of using a technology for zoning hazardous faults developed at the Institute of Physics of the Earth based on natural stress data are presented. The source of these data is catalogs of earthquake focal mechanisms, while inversion of stresses from them is obtained by cataclastic analysis of discontinuous displacements. For the studied region, which includes China’s largest provinces, Sichuan and Yunnan, stresses are reconstructed from a regional catalog of focal mechanisms of earthquakes with Mw = 2.0–6.0 for 1999‒2012. The ability to predict the state of faults is based on data on the normalized values of the isotropic and deviator components of the stress tensor. Two variants of fault zoning are presented, which resulted fromapplication of the Drucker–Prager and the Mohr–Coulomb criteria characterizing the elastoplastic and brittle behavior of the crust, respectively. It is shown that the second approach yields better and more detailed information on the state along the active faults of the western Sichuan region. Analysis of the state of the Longmen Shan fold-and-thrust belt prior to the Wenchuan earthquake that occurred on May 12, 2008, showed that the distribution of Coulomb stresses along the fault with at least 70% of the length, and a high level of Coulomb stresses (>60% of the critical stresses) should be considered hazardous. Based on the tectonophysical zoning findings, more than 20 sites of active faults with lengths of 60–140 km have been identified in the studied region,which we consider as potential sources of strong earthquakes with magnitudes ≥7.0.
