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

作者：Fulong Cai, Lin Ding, Houqi Wang, Andrew K. Laskowski, Liyun Zhang, Bo Zhang, Ali Mohammadi, Jinxiang Li, Peiping Song, Zhenyu Li, Qinghai Zhang · 发表于：Tectonics · 年份：2021 · DOI：10.1029/2021tc006762 · 被引用次数：39 · 研究领域：Geological and Geochemical Analysis、earthquake and tectonic studies、High-pressure geophysics and materials

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