Identification of potential earthquake source locations zones in the Altai-Sayan mountain region: a new approach based on the morphometric terrain analysis and the geodynamic modeling
The usefulness of identifying seismically active zones in the Altai-Sayan region has been demonstrated through the analysis of anomalies in three morphometric terrain parameters (depth of vertical dissection, average height, and difference between second-order and third-order base level surfaces), processed using fuzzy logic tools. According to GNSS data and earthquake focal mechanisms, active faults strike-slip tectonic settings, where the major compression axis strikes northeast. Computer simulations have shown that this process leads to the accumulation of extensional horizontal stress in zones occupying approximately 50% of the investigated area, where 72% of all earthquake epicenters are localized and 83% of those have a moment magnitude of 5.5 or greater. The results of the morphometric terrain analysis and computer simulation enabled the delineation of 13 potential earthquake source zones with moment magnitudes Mw ≥ 5.5. Their configuration aligns well with observed recent seismicity trends and paleoseismological evidence.
