Very-long-range dynamic triggering of mud volcano unrest and silent magnitude-6 fault slip

Seismic waves from large earthquakes are known to trigger slip on distant faults, but the underlying mechanisms remain unclear. Using interferometric synthetic aperture radar and local geodetic and seismic data, we show that the 1000-kilometer-distant, February 2023 Kahramanmaraş earthquakes in southeastern Türkiye triggered deformation and/or eruption at 56 mud volcanoes and centimeter-scale aseismic slip on seven faults over tens of kilometers within the fluid-rich Kura Basin in the West Caspian region. This transient deformation event, with an equivalent moment magnitude of 6.1, was coupled with local inflation below major hydrocarbon fields. We postulate that seismic waves led to a change in pore pressure at depth, which in turn triggered aseismic slip along several crustal faults crossing the basin and its surroundings.