Unveiling Cenozoic Volcanism in the Takab‐Shahindezh Area Induced by Slab‐Mantle Interaction in the Zagros Orogen, NW Iran

The Zagros orogen records the closure of the Neotethys Ocean by northward subduction of the oceanic slab beneath the Iranian plate. Northwestern Iran has undergone episodic volcanism since the Eocene, due to a shift of tectonic regimes from subduction to collision and post‐collisional extension, although the dynamics responsible for such volcanism remain highly controversial. We report new zircon U–Pb ages and geochemical data from the Takab‐Shahindezh volcanic rocks in the NW‐trending Zagros orogen, adjacent to the ENE‐trending Mianeh‐Ardabil fault system, to explore their origin and geodynamic implications. Crystallization ages range from 44 to 39 Ma for the Shahindezh lava to 19‒16 Ma for the Takab lava. Integrated zircon Hf–O isotopes, whole‐rock geochemistry, and Sr‐Nd isotope data suggest that both volcanic suites originated from the partial melting of a subduction‐modified, sediment‐enriched mantle lithosphere, triggered by asthenospheric upwelling during ongoing geodynamic reorganization. We present evidence that the Eocene Shahindezh volcanism developed in a late stage of the Neotethyan subduction. This was followed by the Early‐Middle Miocene Takab volcanism, which originated after subduction ended and slab tearing occurred. Subsequently, slab failure, likely controlled by the Aras‐Mianeh‐Ardabil fault system, triggered widespread Late Miocene‐Quaternary volcanism, including the Sahand and Sabalan volcanoes, across northwestern Iran.