The Features Of Qingshilazi Granite In Da Hinggan Mountains Inner Mongolia Area And Its Tectonic Environments

Daxinganling metallogenic belt plate is composed of the southeastern continental margin of Siberia and the northern continental margin of North China plate. This area is construction superimposed metallogenic region of Paleozoic and Mesozoic tectonic ancient Asian Pacific Rim, where magma formed a EW, NE intrusive rock belt, and magmatic activity is characterized by several stages. Many metal deposits have been found there, most of which related to the Mesozoic tectonic and magmatic activities. Yanshanian magmatic activity is very strong, and has a strong relationship with the mineralization.It is proposed by analyzing the rock’s geological features, chemical features of the rock and geochemical data to explore the tectonic setting, source rocks and the formation and evolution, and also the relationship between granite and mineralization.There are mainly diorite, syenogranite, biotite monzonitic granite, monzonite porphyry, monzogranite in the region, all of which are magmatic rocks.We have delineated the boundaries of granite through field geological mapping. The granite has lithofacies transition from the internal phase to external phase. It changed from medium coarse-grained granitic texture to the medium -fine granitic texture. The intrusive order may be from medium-coarse grained graniteto syenite porphyry to granite to fine granite （spot） rock. Part of the rock has been limonitizated.Zircon U-Pb isotope dating shows that the age of syenogranite unit is around 130Ma, which is the Early Cretaceous, not the previous studied Late Jurassic.Rocks are peraluminous granite, obviously rich in light rare earth and trace elements chondrite REE curve rightist, "V"-shaped, light negative abnormal Eu, which means the characteristics of the crust-mantle mixed-source .Large ion lithophile element content is strongly enriched. The geochemical characteristics of rock unit showed that the sets are strongly peraluminous high-K calc-alkaline series granite. Inner Mongolia Xing’an granite tectonic setting as a whole is transition from POG-type （post-orogenic granitoids） to the CCG type （Continental collision granite）, That is from orogenesis continent-continent collision right down to the orogenic final stage.The granite are generally the product of orogeny.The granite has a feature of low (⁸⁷Sr/⁸⁶Sr_i) andεNd （t）>0 which represent a strong relationship with depleted mantle.