Meng L.,Chinese Academy of Geological Sciences |
Chen B.,Chinese Academy of Geological Sciences |
Luo D.,CITIC Construction Co. |
Wang Y.,Chinese Academy of Geological Sciences |
And 5 more authors.
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2015
Kaladawan area of the eastern Altun Mountains of Xinjiang is tectonically located between the NE-trending Altyn Tagh strike-slip fault and the EW-trending northern Altyn Tagh fault, where the intermediate-acid intrusive rocks are wildly distributed. The granodiorite in the north of Highland 4337 is selected to study the tectonic evolution of the Kaladawan area. The geochemical data of the intrusion suggests that it is high-K calc-alkaline I-type granitic rock which was likely derived from a partial melting of the intermediate-to high-K meta-andesitic-basaltic rocks under high pressure. Zircon U-Pb age obtained by SHRIMP from the granodiorite is (494.4±5.5) Ma, implying that it was emplaced in the Late Cambrian period. Integrated with geochemistry, trace element discrimination, geochronology, and regional background, it is inferred that the granodiorite was formed in a subduction-related active continental margin (continental arc). In combination with the previous studies of magmatic activity in Kaladawan area, we suggest that the central Altun block were developed in Early Paleozoic into an active continental margin (continental arc), and a magmatic belt were caused by the southward subduction of an oceanic crust to central Altun block during Late Cambrian to Early-Middle Ordovician. Compared to the ages of the intermediate-acid intrusive rocks of north Altyn Tagh area, the evolution of western and eastern parts is different. The west of north Altyn Ocean subduction lasted relatively longer than the east, and the syn-collision stage in the east was earlier than in the west. © 2015, Jilin University Press. All right reserved. Source
Yan J.,University of the Humanities |
Yan J.,Key Laboratory of Carrying Capacity Assessment for Resource and Environment |
Yan J.,China University of Geosciences |
Sha J.,University of the Humanities |
And 8 more authors.
Sustainability (Switzerland) | Year: 2014
The stockbreeding industry is growing rapidly in rural regions of China, carrying a high risk to the water environment due to the emission of huge amounts of pollutants in terms of COD, T-N and T-P to rivers. On the other hand, as a typical biomass resource, stockbreeding waste can be used as a clean energy source by biomass utilization technologies. In this paper, we constructed a dynamic linear optimization model to simulate the synthetic water environment management policies which includes both the water environment system and social-economic situational changes over 10 years. Based on the simulation, the model can precisely estimate trends of water quality, production of stockbreeding biomass energy and economic development under certain restrictions of the water environment. We examined seven towns of Shunyi district of Beijing as the target area to analyse synthetic water environment management policies by computer simulation based on the effective utilization of stockbreeding biomass resources to improve water quality and realize sustainable development. The purpose of our research is to establish an effective utilization method of biomass resources incorporating water environment preservation, resource reutilization and economic development, and finally realize the sustainable development of the society. © 2014 by the authors. Source
Li H.-M.,Chinese Academy of Geological Sciences |
Ding J.-H.,Chinese Academy of Geological Sciences |
Zhang Z.-C.,China University of Geosciences |
Li L.-X.,Chinese Academy of Geological Sciences |
And 2 more authors.
Journal of Asian Earth Sciences | Year: 2015
Volcanic rock-hosted iron deposits are among the important iron ores in China. However, the nature of primary magma and petrogenesis associated with these iron ores remains controversial. Here, we report iron-rich fragments (IRF) from the Yamansu iron deposit in Eastern Tianshan Mountains, NW China, which occurs in association with volcanic breccia, submarine volcanic breccia and ignimbrite. The IRF is composed of five types including oligoclase-iron oxide type (OIO), oligoclase-albite-iron oxide type (OAIO), albite-iron oxide type (AIO), albite-K-feldspar-iron oxide type (AKIO) and K-feldspar-iron oxide type (KIO). These fragments display typical volcanic fabric features, such as porphyritic texture, hyalopilitic texture of the groundmass and vesicles filled by minerals to form amygdales. The feldspar phenocrysts of IRF are dominantly albite. The groundmass of IRF consists of magnetite and feldspar. The magnetite is distributed in between the feldspar laths, and together display hyalopilitic texture which could be observed only in volcanic rocks. The vesicles are filled with magnetite, feldspar, chlorite and calcite from the margin to the interior. The IRF has high Si, Al, Fe, Ca, Ti, Na and K contents and low Mg content. The average total Fe is 26wt.%. The magnetite is mostly titanium-vanadium magnetite, with the TiO2 content ranging up to 4.86wt.% and V2O3 content up to 3.20wt.%. The IRF probably came from iron-rich melts and represent the products of the Fenner magma evolution. The basaltic magma evolved into the Fe-Na-rich residual melts by crystallization under low oxygen fugacity condition in a closed magma chamber after intruding into the shallow crust. The Fe-Na-rich residual melts were emplaced in hypabyssal environments or erupted generating the orebodies or providing the material source for the generation of the high-grade iron ores which were subsequently enriched by the late-stage hydrothermal fluids. © 2015 Elsevier Ltd. Source
Liu Y.,Nanjing University of Information Science and Technology |
Zhang J.,Shandong Water Polytechnic |
Zhang B.,Shandong Water Polytechnic |
Sun J.,CITIC Construction Co.
Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica | Year: 2013
In order to solve the computational complexity caused by the consideration of uncertainties in multidisciplinary design optimization (MDO), an efficient method for reliability-based MDO (RBMDO) based on the bi-level integrated system synthesis (BLISS) and performance measure approach (PMA) is proposed. With the decoupling idea of sequential optimization and reliability assessment (SORA) method, the conventional triple nested loop of RBMDO is decoupled into a series of sequential execution of deterministic multidisciplinary design optimization (DMDO) and multidisciplinary reliability analysis (MRA). Both the DMDO and MRA are implemented by BLISS, which avoids the total computation of the whole multidisciplinary reliability analysis model iteratively in each RBMDO cycle. Finally, a shock absorber of landing gear example has been demonstrated to verify the efficiency of the proposed method, which shows that the efficiency of the proposed method has been improved by 52.01% and 26.51% respectively compared to the other two methods. Source
Chen J.,CITIC Construction Co. |
Li H.,Chinese Academy of Geological Sciences |
Luo D.,CITIC Construction Co. |
Li L.,Chinese Academy of Geological Sciences |
And 4 more authors.
Geological Bulletin of China | Year: 2015
Eastern Hebei Province is a main BIF concentration area in China. However, previous studies of BIF in this area which had undergone low-grade metamorphism were relatively weak. Zhalanzhangzi BIF occurs in the Zhuzhangzi Group which has generally suffered from green schist to low amphibolite facies metamorphism. The iron ore predominantly consists of magnetite and quartz, with minor tremolite and biotite. The main chemical constituents of iron ores are SiO2, Fe2O3 and FeO. Low content of Al2O3 and extremely low content of TiO2 as well as High Field Strength Element (HFSE) indicate that the contribution of continental detritus was insignificant. The concentration of REE in iron ores is low, and Post Archean Australia Shale (PAAS)-normalized rare earth elements profiles for the iron ores display depletion of light REE relative to high REE. All samples have distinct positive anomalies of Eu and slightly positive anomalies of Y, the ratio of Y/Ho in iron ores is high, and the typical characteristics of the REY (REE+Y) profiles resemble those of the mixture of high-temperature hydrothermal fluid and seawater, suggesting that the ore material might have been derived from submarine high temperature hydrothermal fluids and sea water. SHRIMP zircon U-Pb dating was conducted for the biotite-plagioclase granulites interlayered with orebodies in the Zhalanzhangzi BIF which are mainly prismatic grains with visible internal zonation. The mean Th/U ratio of 17 zircon samples is 1.02, indicating that they are magmatic zircons. Ten concordantly distributed data with a weighted mean 207Pb/206Pb age of 2572±8 Ma (MSWD=5.8) indicates the formation age of the Zhalanzhangzi BIF. A comparison with previous studies of medium or high-grade metamorphic BIFs shows that BIF underwent different grades of metamorphism that originated from the same sources and formed nearly simultaneously in eastern Hebei Province, and metamorphism of BIF was probably connected with mantle plume event in Eastern Block of the North China Craton at 2500Ma. ©, 2015, Science Press. All right reserved. Source