Han F.,Chinese Academy of Geological Sciences |
Chen B.,Chinese Academy of Geological Sciences |
Cui L.,Chinese Academy of Geological Sciences |
Wang S.,Institute of Xinjiang Geological Survey Research |
And 4 more authors.
Acta Petrologica Sinica | Year: 2012
Kaladawan area of eastern Altun Mountains, is tectonically sandwiched between NE-trending Altun strike-slip fault and EW-trending northern Altun marginal fault. There outcropping a series of intermediate-acid intrusive rocks which were determined as Late Paleozoic era. In this paper, the authors for the first time take measurements of SHRIMP U-Pb zircon age of the intermediate-acid intrusive rocks and give a high quality age of 413 ∼514Ma. The results reflect that there happened a series strong magmatic intrusive activity in Early Paleozoic era. With other dating data of the intrusive rocks by other methods in the area and with SHRIMP U-Pb zircon age of the intermediate-acid intrusive and ophiolite in Hongliugou area about 180km to the west of Kaladawan area, the magmatic intrusive activity in Kaladawan area of eastern Altun Mountains can be divide to three stage as follows: pre-collision(520 ∼500Ma), syn-collision(490 ∼470Ma)and post-collision(440 ∼410Ma).
Chen B.,Chinese Academy of Geological Sciences |
Wang Y.,Chinese Academy of Geological Sciences |
Chen Z.,Chinese Academy of Geological Sciences |
Li S.,Chinese Academy of Geological Sciences |
And 10 more authors.
Earth Science Frontiers | Year: 2015
Kaladawan area is situated in Ruoqiang county of Xinjiang, 620 km to south-east-south of Ürümqi. As a centre-eastern part of first-order Hongliugou-Lapeiquan metallization belt, it is tectonically located in the clamping area between NE-trending Altun strike-slip fault and EW-trending northern Altun Mountains margin fault. The authors made a more thorough investigation on the structural control of the ore deposits in the area. The following knowledges have been gained. (1) The geotectonic setting controls the distribution and position of the first-order metallization belt, in other word, the Altun strike-slip fault and its about 400 km sinistral sense of displacement cut the western part of the northern Qinlianshan metallization belt to present position which is the first-order Hongliugou-Lapeiquan metallization belt. (2) The regional structural environment controlled not only the distribution and position of the second-order metallization belt (ore field), but also the ore genetic type and metallic ore species. In the southern part of the Kaladawan area, the regional structural environment of island arc controlled the volcanic-associated massive sulfide deposit that related to the island-arc type of intermediate-acid volcanic rock. Northern nearby, the regional structural environment of transition zone between the island arc and back arc basin controlled the iron deposit that related to intermediate-basic volcanic rock. In the middle part of the Kaladawan area, the regional structural environment of back arc basin controlled the silica-iron formation deposit that related to sedimentary rock. Southern nearby the north part of the Kaladawan area, the regional structural environment of the ophiolite zone controlled the copper-nickel sulfide deposit that related to ultrabasic intrusive rock (the remain of oceanic crust). In the northern part of the Kaladawan area, the regional structural environment of collision zone controlled the gold deposit that related to ductile or ductile-brittle shear deformation zone and controlled the silver-lead deposit that related to intermediate-acid intrusive rock. (3) The different period of regional structural evolution controlled different metallization and the main mineralization occurred in the early Paleozoic era. In the first period from the late Archean to the middle Proterozoic era, no mineralization was obvious. In the second period from the late stage of the late Proterozoic era to the early stage of the early Paleozoic era (later Cambrian epoch), the extensive tectonic setting in the Hongliugou-Lapeiquan back-arc basin (rift) controlled the mineralization of the iron deposit related to intermediate-basic volcanic rock which is dated by zircon SHRIMP U-Pb age about 517 Ma. In the third period of the middle to late stage of the early Paleozoic era, the underthrust and collision-closure structural setting controlled the mineralization of similar VMS type of lead-zinc polymetallic ore deposit related to intermediate-acid volcanic rock which is dated by zircon SHRIMP U-Pb age as 477-488 Ma (like Kaladaban lead-zinc deposit and Kaladawan cupper-zinc deposit),and controlled the ductile shear zone type of gold deposit related to ductile deformation zone which is dated as 487 Ma by Rb-Sr isotopic data from fluid inclusion in ore (like Dapinggou gold deposit), and controlled the magmatic hydrothermal type of polymetallic ore deposit related to magmatic intrusive activity dating by zircon SHRIMP U-Pb age as 417-514 Ma (like Abei silver-lead deposit). In the fourth period from the late Paleozoic to the Cenozoic era, little mineralization was verified as well. (4) There are four types of ore-controlling structures: volcanic-sedimentary structure (controlled iron ore deposit and lead-zinc deposit), ductile-brittle deformation zone structure (controlled gold deposit), fault or fracture structure (controlled silver-lead deposit and cupper-silver deposit) and structure of rock mass (controlled cupper-nickel sulfide deposit). ©, 2015, Chinese Academy of Forestry. All right reserved.