<p>The Kashan subvolcanic rocks (KSR), located in the central segment of the Urumieh–Dokhtar Magmatic Arc (UDMA), represent a phase of subduction-related magmatism linked to the Alpine–Himalayan orogenic system. These subvolcanic bodies, ranging from intermediate to felsic in composition, mainly consist of microdioritic and granodioritic porphyries emplaced during the Late Eocene and Early Miocene, respectively. Geochemically, the KSR rocks are medium-K, calc-alkaline, and I-type, with SiO₂ contents between 56 and 68 wt.%. They are enriched in large-ion lithophile elements (LILEs) and light rare-earth elements (LREEs), and show depletions in high-field strength elements (HFSEs), with prominent negative anomalies in Nb, Ti, and P, features typical of subduction-derived magmas. Isotopic and trace-element data indicate that the KSR magmas originated from partial melting of a metasomatized lithospheric mantle source beneath the Central Iranian plate, previously affected by subduction-induced modifications. Slab rollback during the early Cenozoic likely played a key role by promoting asthenospheric upwelling and enhancing thermal input to the lithospheric mantle. As the mantle-derived magmas ascended, they experienced assimilation and fractional crystallization (AFC) at shallow crustal levels, resulting in the geochemical characteristics observed in the Kashan subvolcanic suite.</p> Graphical abstract <p></p>