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Zhang Y.,Chinese Academy of Geological Sciences | Xing S.-W.,China Geological Survey | Li C.,National Research Center for Geoanalysis | Liang S.-F.,Institute of Geological Survey of Jilin Province | And 5 more authors.
International Geology Review | Year: 2017

The Changfagou Cu deposit is a newly discovered porphyry deposit located in the southern Jilin Province of Northeastern China, on the northeastern margin of the North China Craton. To better understand the formation of the Cu deposit, we report the zircon U–Pb and molybdenite Re–Os dating, and Sr-, Nd-, and Hf- isotopic data of the granite porphyry. LA-ICP-MS dating of zircon grains from two mineral zones in the granite porphyry yield ages of 115.7 ± 0.8 and 115.3 ± 0.6 Ma, which is interpreted as the emplacement age of the granite porphyry. The molybdenite Re–Os model ages of 112.5 to 113.8 Ma, an isochron age of 113.3 ± 1.3 Ma, and a weighted mean model age of 113.0 ± 0.7 Ma, which represents the age of the Cu mineralization quite well. The Changfagou granite porphyry samples lack amphibole and muscovite, and are compositionally characterized by high SiO2, high Na2O+K2O, and low P2O5, enriched in some Rb, Th, U, and Pb, and depleted in Nb, Ta, Ti, P, and Eu. Mineralogical and geochemical features suggest that the Changfagou granite porphyry samples are slightly peraluminous and are of highly fractionated I-type granitoids. The granitic rocks also have relatively high (87Sr/86Sr)i (0.71199 to 0. 71422), and both low εNd(t) (−14.56 to −13.19) and εHf(t) values (−14.916 to −8.644), which suggest that Changfagou granite porphyry are derived from mixed sources of crustal and mantle, and diagenesis and mineralization were possibly related to the switch in subduction direction of the Palaeo-Pacific Plate in the late phase of Early Cretaceous. © 2016 Informa UK Limited, trading as Taylor & Francis Group.

Shu Q.,China University of Geosciences | Shu Q.,Peking University | Shu Q.,James Cook University | Lai Y.,Peking University | And 4 more authors.
Lithos | Year: 2015

Located in the east section of the Central Asian orogen in northeastern China, the Xilamulun district comprises several newly discovered molybdenum deposits, primarily of porphyry type and Mesozoic ages. This district is divided by the Xilamulun fault into the southern and the northern parts. In this paper, we present new zircon U-Pb dating, trace elements and Hf isotope, and/or whole rock Sr-Nd-Pb isotopic results for the host granitoids from three Mo deposits (Yangchang, Haisugou and Shabutai) in northern Xilamulun. Our aim is to constrain the age and petrogenesis of these intrusions and their implications for Mo mineralization. Zircon U-Pb LA-ICP-MS dating shows that the monzogranites from the Shabutai and Yangchang deposits formed at 138.4±1.5 and 137.4±2.1Ma, respectively, which is identical to the molybdenite Re-Os ages and coeval well with the other Mo deposits in this region, thereby indicating an Early Cretaceous magmatism and Mo mineralization event. Zircon Ce/Nd ratios from the mineralized intrusions are significantly higher than the barren granites, implying that the mineralization-related magmas are characterized by higher oxygen fugacity. These mineralized intrusions share similar zircon in-situ Hf and whole rock Sr-Nd isotopic compositions, with slightly negative to positive εHf(t) ranging from -0.8 to +10.0, restricted εNd(t) values from -3.7 to +1.6 but a little variable (87Sr/86Sr)i ratios between 0.7021 and 0.7074, indicative of formation from primary magmas generated from a dominantly juvenile lower crust source derived from depleted mantle, despite diverse consequent processes (e.g., magma mixing, fractional crystallization and crustal contamination) during their evolution. The Pb isotopes (whole rock) also show a narrow range of initial compositions, with (206Pb/204Pb)i=18.03-18.88, (207Pb/204Pb)i=15.48-15.58 and (208Pb/204Pb)i=37.72-38.28, in agreement with Sr-Nd-Hf isotopes reflecting the dominance of a mantle component. An integration of geochronological and isotopic data points to three stages of Mo mineralization events (i.e., Triassic, Late Jurassic, and Early Cretaceous) associated with magmas generated from three different source regions in the Xilamulun district, NE China. The variation in the origin of the magmas from which the porphyry Mo systems were generated suggests that the formation of Mo deposit lies not in the composition of magma sources. Other factors, including high magma oxygen fugacity, may have taken a fundamental role in Mo enrichment and subsequent mineralization. © 2015.

Shu Q.,Peking University | Lai Y.,Peking University | Wang C.,Peking University | Xu J.,National Geological Library of China | Sun Y.,Peking University
Journal of Asian Earth Sciences | Year: 2014

The Haisugou Mo deposit is located in the northern part of the Xilamulun Mo-Cu metallogenic belt in northeastern China. The Mo mineralization mainly occurs as quartz-molybdenite veins within the Haisugou granite, which was emplaced into rocks of the Early Permian Qingfengshan Formation. Zircon U-Pb dating by LA-ICP-MS of the granite yields a crystallization age of 137.6±0.9Ma, suggesting emplacement during the peak time of Mo mineralization in eastern China, broadly constrained to ca. 150-130Ma, when tectonic stresses shifted from compression to extension. Whole-rock geochemical data suggest that the granite belongs to the high-K calc-alkaline series, and is characterized by relatively high LREE; low HREE; depletion of Ti, Ba, and Nb; and a moderate negative Eu anomaly. The zircon εHf(t) and whole-rock εNd(t) values for the intrusion range from +4.5 to +10.0 and +0.2 to +1.6, respectively, indicating that the magma originated from the juvenile lower crust source derived from depleted mantle, with some component of ancient continental crust. The granite is also characterized by initial (87Sr/86Sr)i ratios ranging from 0.7040 to 0.7074, which suggest some contamination by the upper crust during the ascent of the primitive magma. Moreover, it can be recognized from the whole-rock major and trace element data that significant fractional crystallization occurred during magmatic evolution, with the separation of plagioclase and K-feldspar. Because Mo is an incompatible element and tends to concentrate in the melt during crystallization, fractionation processes likely played an important role in the formation of the Haisugou Mo deposit. © 2013 Elsevier Ltd.

Zhang Y.,Chinese Academy of Geological Sciences | Xing S.-W.,Chinese Academy of Geological Sciences | Wang Y.,Chinese Academy of Geological Sciences | Ma Y.-B.,Chinese Academy of Geological Sciences | And 5 more authors.
International Geology Review | Year: 2014

The Chibaisong magmatic Cu-Ni sulphide deposit is located in Tonghua City, Jilin Province, in the eastern part of the northern margin of the North China Craton. The geological characteristics of the deposit have been investigated, and pyrrhotite Re-Os isotope dating has been utilized to constrain the age. Five pyrrhotite samples separated from the Chibaisong Cu-Ni sulphide deposit yielded a Re-Os isotopic isochron age of 2237 ± 62 Ma (mean squared weighted deviation = 1.13, n = 5), indicating that the only Palaeoproterozoic magmatic Cu-Ni sulphide deposit in China is the Chibaisong Cu-Ni sulphide deposit. The geodynamic setting during ore formation was related to the Liaoning-Jilin Palaeoproterozoic rift split. The Re-Os isotope analyses showed an initial 187Os/188Os ratio of 0.778 ± 0.033, and (187Os/188Os) i and γOs(t) values ranged from 0.7531 to 0.8013 (average 0.7734) and from 574 to 617 (average 592), respectively, indicating that abundant crustal material (5-10%) was mixed with the Cu-Ni sulphide ore system during magma ascent and ore formation. © 2014 Taylor & Francis.

Zhiqian G.,China University of Geosciences | Tailiang F.,China University of Geosciences | Qunan D.,National Geological Library of China | Xiaolan H.,China Huadian Green Energy Company Ltd
Journal of Petroleum Geology | Year: 2016

This paper presents outcrop, petrographic, geochemical, well log and seismic data which together characterise the third-order T7 8 unconformity located between the carbonate-dominated Lower Ordovician Penglaiba and Yingshan Formations in the Tarim Basin, NW China. Unconformities in Lower Palaeozoic carbonates in this basin are of increasing interest because major reserves of hydrocarbons have recently been discovered at the North Slope field (> 1000 × 106 brls oil and ∼ 3050× 108 m3 gas). The reservoir here consists of karstified Lower Ordovician carbonates bounded by a third-order unconformity. The T7 8 unconformity in Tarim Basin represents a short-term exposure surface (< 1 Ma) controlled both by sea-level changes and by palaeogeographic location within the basin, and the intensity of karstification varies laterally. The unconformity has had a major influence on porosity development in the underlying Penglaiba Formation carbonates. At two measured outcrop sections at the NW basin margin (Penglaiba and Shuinichang), dissolution porosity was observed in karstified and dolomitised carbonates below the T7 8 unconformity surface. A seismic profile shows the presence of reflection anomalies below the unconformity which are interpreted as karst-related palaeo-caverns. Geochemical data indicate that the T7 8 unconformity is associated with anomalies in stable isotope ratios and in heavy mineral and trace element profiles. Thus there are negative excursions in δ13C and δ18O ratios within the carbonate rocks immediately below the unconformity surface. Similarly, concentrations of major and trace elements such as Li, K, Ti, Rb, Th, Sr, V and Ni are significantly reduced in the underlying carbonates, while there is an anomalously high content of haematite-limonite. © 2016 The Authors. Journal of Petroleum Geology © 2016 Scientific Press Ltd.

Sun Z.,National Geological Library of China | Fan J.,China Aerospace Geophysical Survey & Remote Sensing Center for Land and Resources | Wang R.,China Zhengyuan Geomatics Co. | Zhao H.,China Aerospace Geophysical Survey & Remote Sensing Center for Land and Resources | And 3 more authors.
Geological Bulletin of China | Year: 2015

Subsidence is a serious environmental geological problem in China and even in the whole world. Synthetic Aperture Radar Interferometry (InSAR) is being developed as a main method for subsidence monitoring. Many geoenvironmental conditions of Jakarta are similar to those in Chinese coastal cities such as Shanghai and Guangzhou. As Jakarta is an important city on the 21st-Century Maritime Silk Road, the research on subsidence monitoring methods in Jakarta can produce experience for the same work in Chinese coastal cities and can also provide valuable information for the 'One Belt, One Road' Initiative. Based on 12 scenes of 3mresolution TerraSAR-X images acquired between June 2010 and March 2011, the authors studied and applied Small BAseline Subsets (SBAS) and 2-pass differential InSAR (DInSAR) methods. On the average subsidence velocity map produced by SBAS, 5 subsidence cones, which are located in west, north and east Jakarta and the northern part of Bekasi City, can be identified, with the maximum velocity up to 9 cm/a. After analyzing the time series 2-pass DInSAR interferograms, it was found that the cone in the northern part of Bekasi City had remarkable non-linear character because its subsidence value could reach 6cm in 44 days between December 2010 and January 2011. It can be concluded that high resolution TerraSAR-X data and proper DInSAR methods can support the work of subsidence mitigation in Jakarta and the similar cities. © 2015, Science Press. All right reserved.

Zhang Y.,Chinese Academy of Geological Sciences | Xing S.-W.,Chinese Academy of Geological Sciences | Song Q.-H.,Institute of Geological Survey of Jilin Province | Wang Y.,Chinese Academy of Geological Sciences | And 4 more authors.
Resource Geology | Year: 2015

Jilin Province in NE China lies on the eastern edge of the Xing-Meng Orogenic Belt. Mineral exploration in this area has resulted in the discovery of numerous large, medium, and small sized Cu, Mo, Au, and Co deposits. To better understand the formation and distribution of both the porphyry and skarn types Cu deposits of the region, we examined the geological characteristics of the deposits and applied zircon U-Pb and molybdenite Re-Os isotope dating to constrain the age of the mineralization. The Binghugou Cu deposit yields a zircon U-Pb age for quartz diorite of 128.1±1.6 Ma; the Chang'anpu Cu deposit yields a zircon U-Pb age for granite porphyry of 117.0±1.4Ma; the Ermi Cu deposit yields a zircon U-Pb age for granite porphyry of 96.8±1.1 Ma; the Tongshan Cu deposit yields molybdenite Re-Os model ages of 128.7 to 130.2 Ma, an isochron age of 129.0±1.6 Ma, and a weighted mean model age of 129.2±0.7 Ma; and the Tianhexing Cu deposit yields molybdenite Re-Os model ages of 113.9 to 115.2Ma, an isochron age of 114.7±1.2 Ma, and a weighted mean model age of 114.7±0.7 Ma. The new ages, combined with existing geochronology data, show that intense porphyry and skarn types Cu mineralization was coeval with Cretaceous magmatism. The geotectonic processes responsible for the genesis of the Cu mineralization were probably related to lithospheric thinning. By analyzing the accumulated molybdenite Re-Os, zircon U-Pb, and Ar-Ar ages for NE China, it is concluded that the Cu deposits formed during multiple events coinciding with periods of magmatic activity. We have identified five phases of mineralization: early Paleozoic (~476 Ma), late Paleozoic (286.5-273.6 Ma), early Mesozoic (~228.7 Ma), Jurassic (194.8-137.1 Ma), and Cretaceous (131.2-96.8 Ma). Although Cu deposits formed during each phase, most of the Cu mineralization occurred during the Cretaceous. © 2015 John Wiley & Sons, Ltd.

Wang C.,National Geological Library of China | Xu S.,Algoma University | Chen L.,Taiyuan University of Technology | Chen X.,Xiamen University of Technology
2016 IEEE/ACIS 15th International Conference on Computer and Information Science, ICIS 2016 - Proceedings | Year: 2016

Libraries play an important role at the intersections of government, universities, research institutes, and the public since they are storing and managing digital assets. The large amount of data and those data in library need to be transformed into information or knowledge which then be used by researchers or users. Librarians might need to understand how to transform, analyze, and present data in order to facilitate knowledge creation. For example, they should know how to make big datasets more useful, visible and accessible. With new and powerful analytics of big data, such as information visualization tools, researchers/users can look at data in new ways and mine it for information they intend to have. In this work, we discussed the characteristics of datasets in library, conducted a review for the research work on library big data and then summarized the applications in this field. The issues associated with it were also discussed and explored. © 2016 IEEE.

Zhiqian G.,China University of Geosciences | Zhongbao L.,Sinopec | Shanlin G.,Sinopec | Qunan D.,National Geological Library of China | And 2 more authors.
Journal of Petroleum Science and Engineering | Year: 2016

Lower Ordovician carbonate successions in the Taxinan area are intensively cemented and filled. Matrix porosity and permeability are low in the Lower Ordovician carbonate reservoirs of the Taxinan area, and reservoir space is composed of karst vugs and fractures. The reservoir space is dominated by four types of karst vug, including vesicular vugs, enlarged dissolved vugs along fractures, tabular vugs and isolated vugs, and three types of fractures, including medium-high-angle fractures, low-angle and horizontal fractures as well as irregular fracture networks. The quality and scale of reservoirs in different zones of the Taxinan area are obviously different, and the best reservoir rock is developed in the eastern part of the Taxinan area. These karstic reservoirs can be divided into three types according to the reservoir formation mechanism, including buried-hill vug-fracture reservoirs, vug reservoirs below unconformity surfaces and deep bedding underflow karst vug reservoirs. Different types of reservoir developed in significantly different successions and areas and are controlled by different factors. Buried-hill vug-fracture reservoirs are mainly developed in the Yingshan Formation and distributed in the fault-uplift zones of the eastern part of the Taxinan area. Their formation is controlled by paleogeomorphology and tectonic movement. Vug reservoirs beneath unconformity surfaces are developed in the Yingshan Formation and distributed in the gentle zone in the central-western Taxinan area. Their formation is controlled by the scale and erosion intensity of the unconformity. Deep bedding underflow karst vug reservoirs are mainly developed in the Penglaiba Formation and distributed in the fault-sag zones between the NE-trending fault-uplift zones in the eastern part of the Taxinan area. Their formation is controlled by paleogeomorphology, rifting and unconformity. Guided by this geological model of reservoir development, combined with drilling, well logging and seismic data, the distribution of favourable high-quality reservoirs in the Taxinan area is predicted. The results showed that the flanks of the fault-uplift and fault-sag zones in the eastern part of the Taxinan area and the haystack hills and karst highlands in the central-western parts of the Taxinan area are favourable reservoir exploration areas. © 2016 Elsevier B.V.

Zhiqian G.,China University of Geosciences | Qunan D.,National Geological Library of China | Xiaolan H.,China Huadian Green Energy Company Ltd
Journal of Petroleum Science and Engineering | Year: 2015

Intra-platform shoals are widely developed in the Cambrian-Ordovician of the Tarim Basin, western China, and are prospective for hydrocarbon exploration. Early Paleozoic tectonic evolution of the Tarim Basin was one of the extensions and was followed by compression. The dynamic transformation of the regional plate margins caused differentiation of the intra-platform paleogeomorphology, which imposed changes in the development of sedimentary facies contemporaneous with the development of intra-platform shoals. An integrated model for the recognition of intra-platform shoals was established through outcrop investigation, core observation, logging analysis and seismic data interpretation. Ordovician intra-platform shoals in the Tarim Basin occur as 'shoal containing reefs', 'shoal covering reefs' as well as 'shoal wrapping reefs' and show different characteristics at different periods. Few but large intra-platform shoals are developed in the Penglaiba Formation. Large numbers of small-scale intra-platform shoals are widely developed in the lower member of the Yingshan Formation, whereas larger and thicker intra-platform shoals are widely developed in the upper member of the Yingshan Formation. Intra-platform shoals show successive development characteristics from Penglaiba to Yingshan Formations. This study indicates that the development of intra-platform shoals is controlled by many factors such as platform structure, sea-level change, paleodepth, hydrodynamic condition, and paleogeomorphology, among which sea-level changes and micro-paleogeomorphology play the most significant role. The shoals are found mainly in highstand system tracts of high-frequency depositional cycles. The ideal locations for the development of intra-platform shoals are over micro-uplifts and facing windward paleoslopes. © 2015 Elsevier B.V.

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