Journal of Asian Earth Sciences 254 (2023) 105727 Available online 15 June 2023 1367-9120/© 2023 Elsevier Ltd. All rights reserved. Review Neotectonics and paleoseismology of the North Tabriz Fault, Azerbaijan Region, Northwest Iran Mohammad Faridi a, * , Jean-Pierre Burg b , Hamid Nazari a , Negar Haghipour b , Mina Faridi c a Research Institute for Earth Sciences, (RIES), PO Box 13185-1494, Tehran, Iran b Department of Earth Sciences, Ion Beam Physics, ETH, Otto-Stern-Weg 5, 8093 Zürich, Switzerland c Department of Computer Engineering, Tehran University, PO Box 11155-4563, Tehran, Iran A R T I C L E INFO Keywords: Tabriz Fault Sahand Volcano Azerbaijan Paleoseismology ABSTRACT Structural characteristics and seismic parameters were investigated to reevaluate seismic hazards along the North Tabriz Fault (NTF). Field surveys and paleoseismology on the central segment of the fault, combined with dating of sedimentary units, document multiple surface-rupturing paleoearthquakes during the past 3.5 ka. The calculated moment magnitudes (M w ) for the identifed paleoearthquakes range from 6.3 to 7.5, causing surface ruptures of ca. 50 km with a maximum slip per event of 5.7 ± 0.2 m. Kinematic GPS surveys on displaced geomorphic features, combined with the dating results indicate that the central segment of the NTF slips at a rate of 6.4 ± 0.5 mm yr 1 over the past 7.5 ka. Fault orientations and scattered volcanic vents in Sahand Volcanic Complex (SVC) suggest that its confguration and evolution have been affected by the regional transpression. 1. Introduction The Tabriz Fault System (TFS) is a NW-SE right-lateral shear zone that extends from the Eastern Anatoly to Western Alborz in the Turkish- Iranian plateau (Fig. 1a). The 95–100 km long NTF, a fault segment between the two E-W trending Misho and Bozgush Mountains, is central to the major strike-slip system (Fig. 1). Several cities and villages, including Tabriz, have been repeatedly struck by the destructive earthquakes (Zoka, 1978). Determination of the seismic parameters and geometric characteristics of NTF is therefore a critical task in evaluating the earthquake risk in NW Iran. In this paper, we present new paleo- seismic and structural data from NTF and deformational pattern of the Sahand Volcano in the area between the NTF and Maragheh Fault (MF, Fig. 1a). Indeed, vulnerable masonry buildings have risen the level of seismic risk. Preparedness and earthquake risk mitigation is a social need for Tabriz, a densely populated and seismic-prone industrial city where developing infrastructures develop. 2. Geological setting The seismicity of NW Iran is mainly attributed to the ongoing, roughly N-S convergence between the Arabian and Eurasian plates (Vernant, 2015). The oblique convergence between the Arabian plate and NW Iran is responsible for active shear zones within fault bounded- crustal blocks. As most of NW Iran exhibits a broad zone of sub-parallel dextral faults, the combined transtension, transpression and block rotation processes have occurred in many areas within the region (Rezaeian et al. 2019). The study area covers the TFS, the NW-SE striking, right-lateral fault zones that have been responsible for several destructive paleoearthquakes (Ambraseys and Melville, 1982; Berberian and Yeats, 1999). The TFS extends southeastward from the northwestern borders of Iran and terminates in the Western Alborz Mountain (Fig. 1). Satellite images show a structural linkage between active faults in eastern Turkey and TFS (Karakhanian et. al., 2004 and Selçuk et. al. 2016). According to GPS data (Djamour et al., 2011; Vernant, 2015) NTF slips dextrally by 7.5–8 mm yr 1 , which is consistent with the 6.5–7.0 mm yr 1 slip rate estimated from displaced fan deposits, to the north- west of Tabriz, for the past 45 ka (Rizza et al., 2013), while paleoseismic studies yield an average slip rate of 6.4 mm yr 1 (Hessami et al., 2003). The TFS exhibits zones of transpressional (restraining) and transten- sional (releasing) deformation developed in fault irregularities and discontinuities, bends and stopovers, and jogs. For example, the Misho and Bozgush Mountains (Fig. 1) exhibit range-parallel, doubly-vergent asymmetric folds and thrust faults refecting transpressional deforma- tion. In addition to the high topographic features, growing of fault- propagation folds in the mountain front(s) led to incision of the rivers, * Corresponding author. E-mail address: mohamadfaridi@gmail.com (M. Faridi). Contents lists available at ScienceDirect Journal of Asian Earth Sciences journal homepage: www.elsevier.com/locate/jseaes https://doi.org/10.1016/j.jseaes.2023.105727 Received 7 January 2023; Received in revised form 15 May 2023; Accepted 19 May 2023