Proceedings of the 12th International INQUA meeting on paleoseismology, active tectonic and archaeoseismology

Fig. 1: Overview of the West Caspian Fault Zone. Black lines are mapped active faults, dotted are inferred from mud volcano alignments. Basin (Fig. 1). The West Caspian Fault separates the Kura Basin from the South Caspian Basin, accommodating northwards motion of the Arabia-Eurasia collision (Jackson et al., 2002; Gunnels et al., 2021). High rates of sedimentation in both basins and fluctuating Caspian Sea levels have overprinted much of the fault trace. However, at fault bends sufficient topography exists to preserve signals of active strike-slip faulting. The West Caspian Fault strikes NNW-SSE from the Greater Caucasus in the north to the Talesh Mountains in the south. The fault breaks through a thick (~15 km) sedimentary cover, with sediments experiencing over- pressure, tectonic compression, and high pore-fluid pressures. As a result, mud volcanism is prevalent in the basin and straddles the fault trace (Fig. 1). The earthquake history of the West Caspian Fault is unknown, despite rich historical records of seismicity regionally (Ambraseys and Melville, 1982). Recent seismic deployments show a small number low magnitude (< Mw 4) earthquakes at depth (Gunnels et al., 2021). As a result of the lack of historical seismic records and poor geomorphic expressionof theWestCaspianFault little is known about deformation in this part of the Caspian-Caucasus triple junction.