Arabia-Eurasia convergence and collision control on Cenozoic juvenile K-rich magmatism in the South Armenian block, Lesser Caucasus

The South Armenian Block (SAB) belongs to the Lesser Caucasus, and it is located where Central Tethyan belt bends from an EW orientation in Turkey NW-oriented Iranian tectonic zones. Magmatism these belts result of convergence, collision post-collision evolution Arabian plate with Eurasian margin. An exhaustive study including whole-rock major, trace element, radiogenic isotope (Sr, Nd, Pb) data, zircon Hf isotopes, U-Pb dating has been conducted three areas SAB, Tejsar, Amulsar Bargushat. Combined previous this reconstructs Cenozoic magmatic geodynamic Turkish-Lesser Caucasian-Iranian belt, a particular focus on SAB. intrusions SAB are dominantly K-rich characterized by enrichment LILE depletion Nb, Ta Ti. They were emplaced Tejsar Bargushat between 43.0 37.7 Ma, 35.9 32.1 predating or being contemporaneous 37.8 28.1 Ma shoshonitic pulse recorded southernmost at Meghri-Ordubad pluton. This magmatism juvenile mantle dominated composition, evidenced ?Hf(i) values higher than 8.1 ?Nd(i) 3.1. Modelling Nd Sr data shows that mid-Eocene early Oligocene low degree partial melting metasomatized source (SCLM), mixing upwelling asthenospheric mantle. Mid-Eocene-early NW Iran coincided lull 40–20 Ma. While frontal Arabia-Turkish totally shut off magmatism, ongoing coeval NW-Iran explained strike-slip fault tectonics during oblique convergence along segment. dominant signature contrasts more crustal-enriched sources adjacent eastern Turkish rocks, revealing anomaly underneath Our concludes compressive tranpressive regime Arabia-Eurasia resulted delamination SCLM, which interacted Low mixed reservoir formation rocks