Liu X.,Xinjiang University |
Zhu Z.,Xinjiang University |
Zhu Z.,Geological Research Academe of Xinjiang |
Zhu Y.,Xinjiang University |
And 3 more authors.
Northwestern Geology | Year: 2015
The Duweituwei granite exposed in western Tiekelike area of the southern Tarim Basin of Xinjiang intrudes into biotite monzo-gneiss of Heluositan terrain (Pt1 H), and contacts by fault withthe Kulangnagu (Pt2K) terrain and west Datong granite. Besides, the east of the granite is unconformably covered by Bochatetage group (Jxbc). Geochemical analysis shows that the granite has high SiO2, Al2O3, K2O content but relatively low CaO, P2O5, TiO2 and MgO content. The ratios of A/CNK vary from 1. 37 to 1. 43, and CIPWcorundum molecule is larger than 1%, suggesting its type of high-K calc-alkaline peraluminous syn-collision granite. The chondrite-normalized REE patterns show that the granite is rich in LREE but depleted in HREE, with high fractionations between LREE and HREE and moderate negative Eu anomalies (δEu is 0. 59 to 0. 82). In addition, the granite is relatively rich in such LILEs as Rb, Ba, Th and K, but poor in such HFSES as Nb, Ta and Ti in the primitive mantle-normalized trace elements patterns. Zircon LA-ICP-MS dating yielded the age of (1 909±47) Ma, implying that the magmatic crystallization epoch of the granite is late Paleoproterozoic. Comprehensive analysis suggests that the rock mass is formed in the late orogenic collision environment relevant to the formation of thickened crust induced crustal remelting. It is therefore speculated that the strong intracontinental orogenic activityin western Kunlun orogenic belt should have begun in the Paleoproterozoic. Combined with the zircon record of hornblende plagioclase gneiss in Heluositan rock group (Pt1H), it is inferred that the Columbia supercontinent events occurred in the Tarim block during 2 000 to 1 800Ma.
Song B.,Chinese Academy of Geological Sciences |
Song B.,Beijing Center |
Li J.-Y.,Chinese Academy of Geological Sciences |
Zhang J.,Chinese Academy of Geological Sciences |
Zhu Z.-X.,Geological Research Academe of Xinjiang
Geological Bulletin of China | Year: 2011
The Targen monzogranite was sheared by the Tuoli fault in the middle of west Junggar and the maximum initial time of left-lateral slip of the Tuoli fault will be limited by the emplacement time of the monzogranite. The sample, light fleshred monzogranite, was collected at N45°45.911', E83°32.584', located at the south of the Tuoli City, 50 meter southeast to the fault plane. The UTh- Pb isotope data of 29 grains, i. e. 31 spots, of zircons in the sample were obtained by using the SHRIMP II in Beijing SHRIMP Center. In all of the data, the 206Pb/238U ages of the zircons are between (279.5±2.7)Ma~(337.3±2.7)Ma, with the Th/U ratios of 0.31~0.88, U contents of 65×10-6~384×10-6 and Th contents of 23×10-6~142×10-6. According to the observation of the very similar CL images of the zircons, the weighted average value of 206Pb/238U age of (295.8±2.5) Ma was obtained by the calculation using 13 among the 31 data, which is interpreted as the emplacement time of the Targen monzogranite. Based on the fact of left-lateral slip sheared and the emplacement time of the Targen monzogranite, it is clearly indicated that the initiation of left-lateral slip of the Tuoli fault took place after 295 Ma.
Yang Z.,No. 11 Geological Party |
Gulibahaer A.,Comprehensive Geological Exploration Team |
Muhetaer Z.,Xinjiang University |
She J.,Geological Research Academe of Xinjiang
Northwestern Geology | Year: 2015
This paper systematically summarized the geochemical characteristics of late Paleozoic igneous rocks in the Jueluotage area of Eastern Tianshan. The igneous rockis mainly formed by early Carboniferous to middle Permian volcanic and intrusive rocks, and its formation is relevant with the northward subduction of Kangguer ocean. The igneous rock of early Carboniferous is composed of calc-alkaline island arc volcanics formed in the initial stage of slab subduction and high-potassium calc-alkaline I-type granite with a characteristic of low temperature and low pressure. The igneous rock of late Carboniferous is post-collision arc volcanics. The igneous rock of early Permian is composed of the volcanic in the post-collision arc and intraplate environment, and I-type granite with a characteristic of high temperature and high pressure. The igneous rock of middle Permian is high-potassium calc-alkaline A-type granite with characteristics of high temperature and low pressure. The results of previous studies and this paper suggest that this region experienced a tectonic evolution from subduction-collision to collision-orogenesis and post-orogenic intracontinental extension in late Paleozoic.
Xu S.,Geological Research Academe of Xinjiang |
Feng J.,Bureau of Mineral Resources |
Tian J.,Bureau of Mineral Resources |
Zhao T.,Geological Research Academe of Xinjiang
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2013
Sixteen deposits, including iron and base metal, copper and lead-zinc have been found in high potential west Kunlun area, an important metallogenic belt in southwestern Xinjiang. Based on the study of the Baotashan and Luoshigou lead-zinc deposits and gravity, magnetic, chemistry and remote sense information, a regional evaluation conceptual model has been set up, regional ore-controlling law of lead-zinc deposits has been summarized and the predictive components have been determined by the present authors. Using weights of evidence law and 12 variables from geology, geochemistry, geophysics, and remote sense, the mineralized posteriori probability is calculated and five smallest predicted areas are delineated by the present authors.Through summarising the geological constrains of lead-zinc deposits, it is concluded that the Luoshigou area of western Kunlun is the most favorable for looking for hydrothermal lead-zinc deposits.
Wang B.,Nanjing University |
Wang B.,Northwest University, China |
Shu L.,Nanjing University |
Shu L.,Northwest University, China |
And 7 more authors.
Precambrian Research | Year: 2014
The North Yili Block is one of the major continental constituents of the Central Asian Orogenic Belt (CAOB), study of its basement evolution and tectonic origin is essential for the understanding of the accretionary history of the CAOB and the reconstruction of global supercontinent as well. We conducted field geological, geochronological and geochemical investigations on the mafic dikes intruding in the highly deformed Proterozoic carbonate in the North Yili Block, NW Chinese Tianshan. Zircon U-Pb dating results suggest that the gabbro and gabbroic diorite dikes and associated granitic vein formed in 776-778. Ma. Element and isotope geochemical data reveal that these intrusive rocks derived from an OIB-like mantle source, and were variably influenced by fraction crystallization and important crustal contamination, thus, a continental rifting setting is proposed for these dikes. Our new data provide the first evidence for a Neoproterozoic continental intra-plate magmatism occurred in the North Yili Block, this event can be linked with the coeval continental rifting-related magmatism in northern Tarim and in other microcontinents within the SW CAOB (e.g., Central Kazakhstan, Kyrgyzstan Middle Tianshan). Based on the comparison on the Neoproterozoic to early Paleozoic stratigraphic sequences between the North Yili and Tarim blocks, it is suggested that the North Yili Block most likely originated from the Tarim Block, and is potentially one additional constituent member of the Rodinia supercontinent. © 2014 Elsevier B.V..