The Sedimentary Timing，source Provenance Of Late Paleozoic Clastic Sedimentary Rocks In The East Junggar，xinjiang

The East Junggar (Eastern Junggar) is a part of the Central Asian Orogenic Belt,and also the important part of Central Asia-Mongolian giant tectonic metallogenicdomain. There are abundant Late Paleozoic terrigenous classtic sedimentary Rocks,which mainly consist of sandstone, siltstone, mudstone, tuff and low metamorphicphyllite, schist. It is favorable for clastic source provenance analysis duringreconstruction of regional tectonic framework. Based on the study of sedimentarypetrology and detrital zircon geochronology of clastic rocks, the sedimentary timingand source provenance of late Palaeozoic strata in the eastern Junggar wasdetermined.the East Jungger can be divided into four tectonic belts: Bogda Arc, YemaquanArc, Dulate Arc and Altai tectonic belt from north to north. The analyzed detritalzirons from late Paleozoic clastic rocks in different tectonic belt are mostly magmaticzircon with oscillatory compositional zoning and better euhedral crystals, and theirpredominant206Pb/238U ages were280~360Ma and the oldest age was1129Ma.New sedimentary timing of late Paleozoic stratum restricted by detrital ziron ageis younger than previous viewpoint. The sedimentary timing of traditional middleDevonian and early Carboniferous formations in Dulate Arc and Yemaquan Arctectonic belts were respectively late Carboniferous and no earlier than late period oflate Carboniferous. In Bogda Arc tectonic belt, the sedimentary timing of upperBogda group was Late Carboniferous to Early Permian insteaded of EarlyCarboniferous, and that of traditional middle Permian Chidi formation may beTriassic.In Yemaquan Arc tectonic belt and Dulate Arc tectonic belts, the detrital zirconage spectrum of late Carboniferous clastic rocks become simple from west to east andfrom south to north, and their source provenances are the Yemaquan magmatic arc and the Junggar area. the age spectra of Chidi formation is simple, and its material sourceis from uplift underlying strata. In Bogda Arc tectonic belt, the varied age spectrumbetween late Permian and late Carboniferous-early Permian indicate the change fromnorthern into southern source provenance. The change of source provenance reflectMiddle-Late Permian tectonic movement, which greatly transformed the ancientlandform pattern.