Lithofacies and petrofacies analysis of the Middle Jurassic siliciclastic sediments of eastern Binalood and their relation with tectonic of source area

The Middle Jurassic siliciclastic sediments are exposed in the Binalood Mountain ranges in NE Iran. They are composed of conglomerate and sandstone with minor amounts of fine grain siliciclastic sediments. Based on Field observations, 13 lithofacies, including Gmm, Gcm, Gmg, Gp, Gh (gravelly), Sh, Sm, Sr, Sp, St, Se, Sl (sandy) and Fl (muddy) and five architectural elements (SG, GB, CH, SB and FF) have been identified. These lithofacies and architectural elements indicated that the Middle Jurassic siliciclastic sediments may have been deposited in gravelly braided type fluvial depositional systems. Petrographic studies led to recognition of two petrofacies, including conglomerates(monomictic and polymictic) and sandstones (quartzarenite, sublitharenite and litharenite) Sandstone petrofacies analysis show that these sediments derived from recycled orogenic tectonic setting. The recycled orogenic provenance in northeast Iran has formed between Turan and Iran plates during closure of Paleo-Tethys (Late Triassic time). This closure created a foreland basin and the Middle Jurassic siliciclastic sediments were deposited in this basin. We hope these data can help in a better understanding the tectonic setting in NE Iran.