Configuration and Timing of Collision Between Arabia and Eurasia in the Zagros Collision Zone, Fars, Southern Iran

The configuration and timing of the Arabia-Eurasia continental collision, part broader Alpine-Himalayan collisional system, remains controversial. We conducted sandstone petrology, detrital zircon U-Pb-Hf isotopic trace element analysis, Cr-spinel electron microprobe geochemical analysis samples from Paleocene to Miocene peripheral foreland strata in interior Fars, southern Iran. These data were used test competing models for ophiolite obduction collision. In addition, we applied these compare history outward upward growth Zagros Himalayan-Tibetan segments orogenic belt. first appearance radiolarian-rich chert conglomerate, 100–90 Ma zircons with positive ?Hf(t) values +1 +20 midocean ridge affinity, suprasubduction zone (SSZ) affinity is lower middle Sachun Formation. indicate that occurred before deposition upper Maastrichtian-lower Formation developed an intra-oceanic setting rather than collision setting. Abundant continental-arc 180–160 50–27 age-probability peaks varied are present Oligocene-lower Razak Agha Jari formations, indicating sedimentary overlap Eurasia. SSZ-affinity all indicates ophiolitic rocks a continual source detritus basin since Paleocene. depositional age basal between 25.7 21.5 Ma. Therefore, interpret Arabia Eurasia must have been initiated