Dating Continental Subduction Beneath the Samail Ophiolite: Garnet, Zircon, and Rutile Petrochronology of the As Sifah Eclogites, NE Oman

Studies of the high-pressure (HP) As Sifah eclogites in NE Saih Hatat Window, Oman, have used different combinations radiometric dating results (Ar/Ar, Sm-Nd vs. U-Pb, Rb-Sr) to interpret disparate tectonic models for timing, geometry, and cause continental subduction—including its relationship Samail Ophiolite. To determine timing subduction, we coupled petrochronological analyses major (garnet) accessory phases (zircon rutile) from highest grade metamorphic rocks (As eclogites) Hatat. Early Permian (283.8 ± 0.7 Ma) tuffaceous zircon cores are consistent with earlier interpretations that were sourced a distal portion Arabian margin. Data range bulk compositions assemblages consistently suggest single event garnet growth ?81 77 Ma—though slight, offsets (re)crystallization between lithologies. These new data confirm previous HP metamorphism NE-dipping subduction zone beneath obducted Ophiolite; there is no robust evidence an ?110 Ma or SW-dipping plate. Combined other constraints, our unit was subducted at rates similar small bodies, followed by two stages cooling exhumation—likely associated dragging mantle depths mafic root, initial phase rapid exhumation depths, lengthy residence (?40 My) lower middle crust.