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The Pamir Frontal Thrust (PFT) of the Trans‐Alai Range in Central Asia is the principal active fault of the intracontinental convergence zone between the Pamir and Tien Shan. Its northward propagation is reflected by frequent seismic activity and ongoing crustal shortening. Recent and historic earthquakes exhibit complex rupture patterns within and across seismotectonic segments bounding the Trans Alai, challenging our understanding of fault interaction and seismogenic potential. We provide paleoseismic data from five trenches along the central PFT segment (cPFT) and interpret five and possibly six paleoearthquakes that have ruptured since ∼7 ka and 16 ka, respectively. Our results indicate that at least three major earthquakes ruptured the full‐segment length and possibly crossed segment boundaries with a recurrence interval of ∼1.9 kyr and potential magnitudes of up to Mw 7.4. We did not find evidence for great (i.e., Mw ≥8) earthquakes. However, discrepancies between slip and rupture extent during apparent partial segment ruptures in the western half of the cPFT, combined with significantly higher scarp offsets, indicate a more mature fault section with potential for future fault linkage. We estimate an average rate of horizontal motion for the cPFT of 4.1 ± 1.5 mm/yr during the past ∼5 kyr, which does not fully match the GNSS‐derived present‐day shortening rate of ∼10 mm/yr. This suggests a complex distribution of strain accumulation and potential slip partitioning between the cPFT and additional faults and folds within the Pamir that may be associated with a partially locked regional décollement.

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<p>The Pamir Frontal Thrust (PFT) constitutes the northernmost boundary of the Pamir mountain range at the NW edge of the India-Eurasia collision zone. Due to the ongoing collision this active system propagates into and overthrusts the Quaternary deposits of the Alai Valley, an intermontane basin separating the Pamir from the Tien Shan in the north. Geodetic data across the Central Pamir document a shortening rate of 25 mm/yr, with a dramatic decrease of ~10 mm over a short distance across the northernmost Trans-Alai range (250 km aperture); this suggests that almost half of the shortening in the greater Pamir – Tien Shan collision zone is absorbed along the PFT.</p><p>Consequently, the frontal thrusts must accommodate a significant amount of slip and may be capable of generating ≥M7 earthquakes in this part of the orogen. In contrast to similar tectonic settings along the Himalayan megathrust, the present-day seismicity in the Pamir apparently does not reflect the long-term deformation history. Despite few studies in the late 20<sup>th</sup> century, and an extensive data base of recent earthquakes, the relationships between seismicity and the geometry of the thrust zone are not well understood. In this context our study aims to improve the understanding of the earthquake geology of the PFT by asking two principal questions: (1) How much of the PFT is activated during an earthquake rupture? (2) Does the paleoseismic slip history agree with the geodetically-derived shortening rate?</p><p>Here, we present our results of five analyzed paleoseismic trenches that reveal the youngest manifestation of thrusting along the central segment of the PFT. We combined field-based observations with a TanDEM-X data, UAV-based DEMs, and dGPS profiling for an offset analysis along the fault scarp. The interpretation of the trench stratigraphy and event horizons in the context of these tectonic landforms was combined with radiocarbon and luminescence dating to develop an earthquake chronology.</p><p>We find robust evidence for at least three surface-rupturing events during the past 6 kyr. At least one event can be recognized in all five trenches separated by ~10 km, indicating a full-length activation of the central fault segment during rupture. Ages obtained from uplifted fluvial terraces coupled with the total cumulative fault offset indicate a Holocene slip rate of up to 3.5 mm/yr. Based on dip-slip motion offsets per event we estimated an average earthquake paleo-magnitude ranging between M6.5-7.0.</p><p>Despite the regional extent of the central PFT, and a rather high displacement gradient across it, our results suggest a seismic behavior characterized by strong surface-rupturing earthquakes, short surface ruptures, and low slip rates. Earthquakes along this structure do not cover the total geodetic shortening, which suggests that a strongly segmented PFT system may be linked with active seismogenic deformation in the alluvial-fan covered piedmont regions to the north. However, the preservation potential for fault scarps in the piedmont may be low in this highly dynamic environment due to climate-driven fluvial and glacial processes in the high sectors of the Pamir.</p>