Petrological Characteristics And Genesis Of The Qingtashan Rock Mass In The Western Segment Of The East Kunlun Mountains

The study area is located in the western section of East Kunlun.According to the newly constructed 1:2.5 million Chinese intrusive rock tectonic map,the study area is located in the southeastern margin of Tarim and its southeastern tectonic magmatism.The Late Paleozoic to Triassic is the East Kunlun complex intrusive(rock)arc.Based on the field geological survey,petrological petrology,petrochemical characteristics,zircon U-Pb geochronology and Sr-Nd isotope geochemistry of the Qingtashan rock mass in East Kunlun,the following results and understandings are obtained:1.There are two main types of rock types in Qingta Mountain: tonalite and quartz-bearing quartz diorite porphyry,both of which are products of magmatic action in the same period,all of which belong to low-potassium to medium-potassium-calcium-alkaline series and sodium.Granites,aluminum to weakly aluminous,belonging to the series of magnesium diorite.2.The Qingtashan rock mass is generally enriched in K,Rb,Th,Pb,Th,U,Sr,Sm,loss Nb,Ta,P,and the rare earth distribution curve is right-dip,which is a light rare earth enrichment type with no obvious negative enthalpy.abnormal,.3.The LA-MC-ICPMS test weighted average ages of tonalite and garnet quartz cloud diorite porphyry are 212±1.5Ma and 214±1Ma,respectively,which are late Triassic intrusions.4.The garnet in the Qingtashan rock mass is characterized by high pressure and is derived from the subduction oceanic crust.The tectonic setting of the Qingtashan rock mass is an oceanic subduction environment,which is the product of the partial melting of the subduction oceanic slab and the reaction of the overlying mantle wedge peridotite.Its petrochemical and mineralogical characteristics show high pressure characteristics,which is MA.Series of high pressure type tonalite.