Abstract:
[Objective] The early Cenozoic collision between the Indian and Eurasian plates triggered multi-stage uplift of the Tibetan Plateau, resulting in its remarkable landscapes and abundant mineral resources, while profoundly influencing climate, environment, and hazard evolution across Asia and beyond. Tibetan Plateau and its surroundings have undergone intense tectonic activity and recurrent natural disasters, particularly earthquakes, which have significantly shaped its tectonic and geomorphic evolution. Seismic records indicate that more than half of major earthquakes in Chinese mainland and surrounding regions occur within the plateau and its margins, controlled by active faults of diverse types, scales, and distributions. [Methods]This study synthesizes decades of research on active faults and earthquake hazards across the Tibetan Plateau. Building on the results of the Active Faults and Earthquake Hazards theme of the Second Tibetan Plateau Scientific Expedition and Research Program (STEP), which provided detailed documentation of major active fault zones, current deformation fields, seismicity, and stress regimes were integrated to examine the seismotectonic settings associated with strong earthquakes across different regions of the plateau. Based on this analysis, the future seismic hazard potential of the plateau was further evaluated. [Conclusion]The image of active faults on the Tibetan Plateau indicates that different regions comprise fault systems with diverse scales, kinematics, and activity patterns. The tectonic settings associated with strong earthquakes have evolved through prolonged, multi-stage deformation, progressively establishing the present seismotectonic framework governing the nucleation and occurrence of large earthquakes. Current patterns of crustal deformation reveal northeastward deceleration with limited eastward extrusion of crustal blocks. Stress regimes, in contrast, are characterized by shear–extension in the interior and compression along the margins. Seismic hazard trends inferred from active tectonics and crustal deformation suggest a distinct segmented zonal pattern of strong earthquake activity, with plateau margins and fault-dense interiors representing the primary loci of future large earthquakes. Additionally, tectonic and geomorphic boundary zones display increasing potential for strong seismic events.
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