The relation between composition and provenance ofSiliciclastic sediments (Middle Jurassic) with tectonic Setting in eastern Binaloud, southwest Mashhad
Aghonge conglomerate (Middle Jurassic) is part of the BinaloudMountain, which exposes south and southwest of Mashhad. These stratigraphic sections measured at Aghonge, Kortian and Hesar. This stratigraphic unit at the Aghonge section is mostly composed of conglomerate and sandstone, and in the Kortian section comprised of conglomerate with sandstone and a few shale horizons while at the Hesar section consists of intermittent conglomerate with sandstone and shale. Compositionally, at the Aghonge and Kortian region is mainly composed of quartz with a less than 5 percent rock fragments while in Hesar, the particles are mainly composed of quartz with 20 to 40 percent rock fragments. The petrofacies of sandstone in the Aghonge and Kortian region is quartzose, while in the Hesar region is quartzolithic. These sediments in the studied area were a fluvial environmental system (braided river). Analysis of paleocurrent show that this river flowed from southeast toward Northwest in the study area. Based on the relation between sandstones composition and provinence with Tectonics setting, can be coucluded that these sediments derived from recycled orogens, thrust-fold belts and suture zones that formed in south of Mashhad as the result of collision between Iran and Turan plates during upper terriassic and are deposited in a forland basin.