Detrital Zircon U-Pb Age and Geological Significance of Metamorphic Strata at Gouli Area in the Central Tectonic Belt of East Kunlun

The composition and structures of the central tectonic belt in East Kunlun are very complicated, and the low metamorphic strata in Gouliarea serve as important parts of the central tectonic belt, so the study on the formation age, properties and sedimentary source of these metamorphic strata has important geological significances. In this paper, the metamorphic sandstone samples from the metamorphic strata in Gouli Area have been selected as the research objects, the detrital zircon LA-MC-ICP-MS U-Pb geochronology analysis has been conducted. Detrital zircon U-Pb age spectrum of the sandy slate samples can be divided into four groups:①The Caledonian (499~565 Ma). ②The Early-Middle Neoproterozoic (693~969Ma). ③Late Paleoproterozoic-the middle Mesoproterozoic (1 254~1 967Ma). ④The Neoarchean-early Paleoproterozoic (2 348~2 776Ma).The age group information indicates that, the formation ages of low metamorphic strata vary from 427Ma to 499Ma, belonging to the meta-sedimentary rocks of Early Paleozoic Naij Tal Group-complex. The sedimentary sources of epimetamorphic strata might response to the convergence and cracking of Rodinia supercontinent during Early-Middle Neoproterozoic, which were mainly sourced from the Neoarchean-Proterozoic crystallization basement, with few of them were came from the Caledonian magmatic rocks related to the the extention and subduction of the Proto-Tethys ocean in East Kunlun region. Therefore, the matrix strata of Gouli area in the central tectonic belt may be the meta-sedimentary rocks of Early Paleozoic Naij Tal Group-complex, which is different to the Carboniferous strata classified by the predecessors, and the main tectonic activities of the central tectonic belt had basically completed in the late Paleozoic.