Research On Geological Characteristics,Tectonic Environment And Petrogensis Of Intrusive Rocks In Alastuo Gold Deposit, Western Tianshan Mountains,Xinjiang

Alastuo Gold deposit is located in Nalati-Hongliuhe suture zone at West Tianshan Mountains, having strong Magma tectonic activities, The mafic and acidic intrusive rocks are exposed and it not only has The series of The rock combination by the formation of Magma evolution but also has the Transitional rock types formationed by the magma evolution and magma mixing, Including granodiorite, monzonite granite, granite and a small amount of granite porphyry veins, diorite and diabase dikes and so on. Systematic study of the rock mass made herein,Based on the features of rock and inclusions on the macro, The Mineralogy and structural features On the micro, and the Rock geochemical characteristics, The chronology of rock mass characteristics, Tectonic environment characteristics of granite, the source rock characteristics and petrogenesis analysis and so on. Achieving the following understanding:1. The rock of Alastuo Gold deposit has rich magma unbalanced mixing characteristics on field geological and petrography. Surging formula intrusive contact relationship between invasive bodies, no obvious lithological boundaries, developmental reverse veins, developmental unbanlanced mixing strips and inclusions, xenoliths, mafic mass in rock; xenocryst characterized in having a plastic flow, including feldspar xenocryst of host rocks; Under the microscope, with irregular proliferate edges, plagioclase abnormal annulus, harbour dissolution shape and coarse augen quartz xenocryst which is rimmed by dark minerals, hornblende wrapped hornblende, unbalanced mineral assemblages and rock structure are uncoordinated, acicular apatite and corrosion zircon which exist in inclusions showed the characteristics of magma mixing.2. Alastor Goldfields intrusive rocks are mixing by a role in the formation of granodiorite and inclusion, basic end-yuan(diabase), acidic side yuan(granite, monzonite granite, granodiorite and granite porphyry) of three parts constitute.3. According to the study of the LA-ICP-MS U-Pb isotope chronology of the granodiorite from the Alastuo yielded an age of 350.3±3.0Ma, for the begin of Early carboniferous.4. From the main volume, trace REE characteristics shows that basic end-member diabase originated from partial melting of mantle source material contaminated by the shell; acid end element granite source rocks of the upper crust poor sandy clay rocks.5. Through the geochemical characteristics of the area, geochronology, combined with regional geological data suggest that, in this area as A-type granites granite, formed after the collision extensional tectonic environment.