The Geological Significances,Composition and Age of the Monzonitic Granite in Kendekeke Iron Mine

Hercynian-Indosinian orogenic cycle of East Kunlun underwent the post orogenic extending stage in the middle-late Triassic Epoch and was associated with large intermediate-acidity magmation,in which the monzonitic granite in Kendekeke iron mine is the host rock of the skarn-type iron ores.Geochemical analyses indicate that the monzonitic granite has the characteristics of metaluminous-weak peraluminous A-type granite,that formed in post orogenic extending environment;LA-ICPMS zircon U-Pb dated a concordant age of(230.5±4.2)Ma(n=7,MSWD=1.4),represented the rock formation age,and it is likely to be the product of lower-crust suffered anatectic melting,which was caused by the heat source of basaltic magma underplating during the apotectonic lithosphere extension,and it is the product of late Indosinian magmatic activity.