Akademik Veri Yönetim Sistemi
JOURNAL OF SEISMOLOGY, cilt.30, sa.29, ss.644-657, 2026 (SCI-Expanded, Scopus)
The long-lasting aseismic period of 1200 years in a slowly deforming mountain belt of NW-Afghanistan, isolated from inter-plate settings was disrupted by the 2023 NNW-Herat earthquake sequence. This unusual sequence underscored the critical need for a thorough scientific research in the area, given its rarity. Sparse observational opportunity and absence of an available station network posed a significant challenge in accurately constraining the sequence, resolving the rupture structure, drawing novel hypotheses and raising an open question related to what drives the current sequence in detail. In this study, teleseismic data was used to derive the co-seismic slip distribution associated with this sequence, demonstrating bilateral co-seismic rupture and radial slip propagation patterns with a maximum slip of 75–125 cm. The resolved rupture models constrained from co-seismic deformation suggest that the major slips in the seismic sequence were dominated by the W-E, NW–SE-striking pure thrust faulting concentrated at a shallow focal depth of 8–14 km. This was characterized by N-dipping, low angled sub-horizontal planes of 30°-36° and corresponded to a sliding structure of 85°-124° in a shallow layer, both of which were linked by a "package" of bounded, imbricated thrust sheets, collectively known as a “duplex”. These unknown blind ruptures manifested as “isolated compact asperities” with “patched fault slips”, generally corresponding to the four major duplex thrusting events. Given the co-seismic distributional pattern of these slips using the point-source and finite fault-source inversions, these resolved rupture model solutions should be consecutive occurrences of the four events due to a strong blind duplex thrusting interaction. We suggest that the locked duplex package acts as an obstacle to slow-motion collision, and ruptured sequentially in a 32 km-wide and 40 km-long NW-segment of the ~ 700 km-long Herat left-lateral strike-slip fault system to accommodate plate-scale N-S shortening in an area of ~ 1250 km2.