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Major strike-slip fault systems on Earth, like the North Anatolian Fault (NAF), play an important role in accommodating plate motion, but surprisingly little is known about how such structures evolve through space and time. Along the central sector of the NAF in the Central Pontides, transpression and crustal thickening along the northward restraining bend of the fault are thought to have generated rock-uplift rates of 0.2–0.3 km/Myr since at least 400 ka based on Quaternary marine and river terraces, while data from low-temperature thermochronology suggest that an enhanced exhumation phase occurred within the last 11 Myr. However, the precise onset of this faster uplift phase, which likely reflects deformation associated with the development of the central sector of the NAF, is poorly constrained. Here we define the spatiotemporal pattern of rock-uplift rates within the Central Pontides over the last ∼10 Myr by performing linear inversions of 19 river profiles that drain the northern margin of the Central Pontides, from the Sinop Range to the Black Sea. We use 21 new 10Be-derived basin-average denudation rates to calibrate an erodibility parameter, which we use to convert our χ -transformed river profiles into rock-uplift histories. Our results document an increase in rock-uplift rates after 10 Ma, with peak rates of ∼0.15–0.25 km/Myr occurring between 4 and 2 Ma. Moreover, the spatiotemporal pattern of uplift suggests that faster rock uplift started in the eastern part of the Sinop Range and migrated westward over a period of ca. 2 to 2.5 Myr, which we relate to the westward propagation of the NAF through this sector at a rate of 74 ± 13 km/Myr. In the context of previously published constraints on the westward propagation of the NAF starting in eastern Turkey at ∼12 Ma, our results suggest differences in fault-propagation rates that coincide with differences in the orientation of the NAF relative to plate-convergence velocity vectors. Fault segments with higher obliquity appear to have propagated at rates up to 2-fold slower than those oriented more parallel to the plate-convergence vector. • Rock-uplift history of Central Pontides from river linear inversions. • The uplift event after 10 Ma dates the arrival of the North Anatolian Fault (NAF). • The uplift migration provides the propagation rate of the NAF central segment. • New insights about the propagation history of all the NAF segments. • Linkage between NAF propagation rates and plate convergence directions. [ABSTRACT FROM AUTHOR]

Abstract: We present results on imaging contrast of seismic velocities across the Mudurnu segment of the North Anatolian Fault Zone (NAFZ) in northwestern Turkey with polarization analysis of early P waveforms generated by near-fault seismicity and recorded by near-fault stations. The analysis uses changes in motion polarity from fault–normal to source–receiver directions to identify early-arriving fault zone head waves on the slow side of the fault, and measure the arrival times of the head and direct P waves. The moveout between the head and direct waves with increasing source–receiver distance along the fault provides an estimate of the average contrast of seismic velocities across the fault. The results indicate that the average contrast of P wave velocities across the Mudurnu segment of the NAFZ is at least 6%, with the south block being the faster side. The findings provide a basis for deriving improved event locations, focal mechanisms and estimated shaking hazard associated with earthquakes on the fault. The analysis technique can be used in other fault zones monitored with sparse seismic instrumentation. [Copyright &y& Elsevier]