Precambrian tectono-thermal events of the northern margin of the Tarim Craton: Constraints of zircon U-Pb chronology from high-grade metamorphic rocks of the Korla,Xinjiang

Zircon U-Pb chronology of high-grade metamorphic rocks from the northern margin of the Tarim Craton,was reported in this paper.The metamorphic rocks located on the Tiemenguan of northern Korla,was composed of gneiss,schist,amphibolite and calc-silicate rocks.They have mineral assemblages of plagioclase+K-feldspar+quartz+biotite±muscovite±hornblende±garnet,indicating amphibolite-facies conditions.The zircon U-Pb dating demonstrates that these high-grade metamorphic rocks have been subjected to three-stages of tectono-thermal events,i.e.the Early Paleoproterozoic magmatic event of ~2370Ma,the Late Paleoproterozoic metamorphic event of 1890~1850Ma and the Early Neoproterozoic metamorphic event of 980~910Ma.These results supply significant constrains on Precambrian tectonic evolution of Tarim Craton.