Genesis And Geological Significance Of The Ophiolites In The Southeastern Margin Of The Central Tianshan Tectonic Belt, NW China

The ophiolite belts outcropped in Tianshan mountain recorded the significant geologicalinformation of Paleo-Asian Ocean in the ocean-continent transition process, and they are theonly remnants of ancient oceanic crust and upper mantle of Paleo-Asian Ocean of billions ofyears preserved up to now. The thesis selected the Hongliuhe Ophiolite(HLHO) of theSoutheastern margin of the Central Tianshan tectonic belt, NW China as the study objectamong them, to certify its material composition, type, petrogenesis and tectonic setting, andto further know where is the boundary between the Tarim plate and the Kazakhstan plate,what is the tectonic attribute of the Central Tianshan, and the relationship between the HLHOand the ancient oceanic evolution.To achieve the amid above mentioned, We used the geochemistry as the fingerprintingand the modern geological theory as the research guide. In the research process, this studyfocus on the field working investigating, collected data through previous works, and dependon modern experimental methods. Furthermore, The geochemistry data was obtained throughconducted tests of major elements and trance elements on each rock units from the HLHO,and then the characteristics of petrology and geochemistry of the HLHO was analyzed.Finally, this thesis concluded that the HLHO belongs to the SSZ ophiolite, subduction-relatedophiolite, caused the southern Tianshan ocean northern toward subducted, and formed at ageological setting of forearc. The magmatic origin of HLHO is probably the mantle sourcemixed the crustal source caused by subduction. The model of relationship between the HLHOand the evolution of the ancient southern Tianshan Ocean also have been established. It havebeen considered that the HLHO, a part of southern central Tianshan tectonic belt, is the sutureof the Tarim plate and the Kazakhstan plate.