Underestimated seismic hazard in the south of the Issyk-Kul Lake region (northern Tian Shan)

A significant underestimation of seismic hazard exists in the southern Issyk-Kul Lake region, part of the UNESCO-listed Western Tien-Shan. Recent research identified active tectonic structures, including faults and folds linked to the South Issyk-Kul Fault, which have caused strong earthquakes (magnitude ≥ 7) in historical and paleoearthquake events dating back to the Holocene and Late Pleistocene epochs. These seismic activities, evidenced by fault scarps and rockslides, were previously unrecorded in this region. The study also revealed deformations in archaeological monuments, supporting the presence of epicentral areas for strong earthquakes (intensity ≥ IX). A model describing a fault rupture plane that becomes shallower southward, complicated by reverse thrusts, was proposed. This indicates the existence of a long-lived fault zone separating structures with different movement regimes during Neotectonic time, highlighting the need to reassess seismic risk in this region.

Korzhenkov, A. M., & Deev, E. V. (2017). Underestimated seismic hazard in the south of the Issyk-Kul Lake region (northern Tian Shan). Geodesy and Geodynamics, 8(3), 169–180. https://doi.org/10.1016/j.geog.2017.03.012