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SHRIMP Zircon U-Pb Ages of the Manketouebo Formation in the Southern Manzhouli Area,Northeast China

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Acta Geologica Sinica(English Edition) 2019年第2期93卷 487-488页

作者： MI Kuifeng CHENG Shaobo ZHAO Shengjin Development and Research Centre China Geological Survey School of Earth Sciences and Resources China University of Geosciences China Deep exploration Center-SinoProbe Center Chinese Academy of Geological Science no.10 institute of geological exploration Inner Mongolia Bureau of Geology and Mineral Resources

Objective The Great Xing’an Range is located in the eastern Central Asian Orogenic Belt and contains a Mesozoic volcanic belt that crops out over an area of 100, 000 km^2,dominating the Mesozoic stratigraphy of the G... 详细信息

关键词： Pb Th Ages Manketouebo Formation

Isotope tracers for deep-seated fluids and noble gases

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Chinese Journal Of Geochemistry 2013年第2期32卷 195-202页

作者： WANG Baode NIU Shuyin SUN Aiqun ZHANG Jianzhen WANG Xiang WANG Chuen Institution of geological Survey Shijiazhuang University of Economics Qingdao institute of geological Engineering and exploration

The role of He and Ar isotopes in tracing the source of ore fluids has aroused great attention of the broad masses of the geological researchers. On the basis of lots of test and measurement of He and Ar isotopes in sulfides from Au, Ag polymetallic ore deposits in northern China, statistics has been made on the published He and Ar isotope data from 27 gold deposits, 13 silver polymetallic ore deposits, 8 polymetallic ore deposits, 1 rare-earth deposit, 3 oceanic incrustations, 3 volcanic springs and their wall rocks and granites. The statistical results indicate that the 3 He/ 4 Ar (×10-6 ) values of the Au, Ag polymetallic ore deposits are within the range of 0.24 9.39, with an average of 3.34×10-6 ; the He/Ar values, 0.007 6.01,with an average of 2.37; the 40 Ar/ 36 Ar values, 265.75 2361, with an average of 699.0; the 4 He/ 40 Ar values, 0.0020 643.86, with an average of 5.85, the 3 He/ 4 Ar (×10-6 ) values of gneiss and granite surrounding the mining area, 0.001 1.79, with an average of 1.00×10-6 , reflecting great differences in source. Mantle-source He in 48 Au, Ag polymetallic ore deposits accounts for 4.55% 83.06%, averaging 29.91%. It falls near the mantle-source region which can be seen in the He isotopic concentration diagram and the 3 He/ 4 He(R/Ra) 40 Ar/ 36 Ar plot. Studies suggested that the ore-forming materials for endogenic Au, Ag polymetallic ore deposits should be derived from the deep interior of the Earth, and with the multi-stage evolution of mantle plumes the deep-seated ore fluids would be transported from the deep interior of the Earth to the shallow levels. During this process the mixing of crust/mantle-source fluids would inevitably occur, therefore, the value range always lies between the mantle and the crust.

关键词：成矿流体同位素示踪稀有气体银多金属矿床氦同位素氩同位素幔源流体地球内部

Geochronology, Geochemistry, and Hf Isotopic Compositions of Monzogranites and Mafic-Ultramafic Complexes in the Maxingdawannan Area, Eastern Kunlun Orogen, Western China: Implications for Magma Sources, Geodynamic Setting, and Petrogenesis

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Journal of Earth Science 2019年第2期30卷 335-347页

作者： Jiaming Yan Guosheng Sun Fengyue Sun Liang Li Haoran Li Zhenhua Gao Lei Hua Zhengping Yan College of Earth Sciences Jilin University The Eighth institute of Shandong geological exploration Qinghai Provincial Bureau of Ferrous Metal and geological exploration

This paper presents zircon U-Pb-Hf isotopic compositions and whole-rock geochemical data for monzogranites and mafic-ultramafic complexes of the Maxingdawannan area in the western end of the east Kunlun orogenic belt, western China. The data are used to determine the ages, petrogenesis, magma sources, and geodynamic setting of the studied rocks. U-Pb zircon dating indicates that monzogranites and gabbros of the complexes were emplaced at 399 and 397 Ma, respectively. The monzogranites are shoshonitic, with high SiO2, Al2 O3 and total-alkali contents, and low TFeO, MgO, TiO2 and P2 O5 contents. The mafic-ultramafic complexes are characterized by low Si O2 contents. The monzogranites display enrichment in light rare-earth elements(LREE) and large-ion lithophile elements(LILE), depletion in heavy REEs(HREE) and high-field-strength elements(HFSE), and negative Eu anomalies(Eu/Eu*=0.36–0.48). The mafic-ultramafic complexes are also enriched in LREEs and LILEs, and depleted in HREEs and HFSEs, with weak Eu anomalies(Eu/Eu*=0.84–1.16). Zircon εHf(t) values for the monzogranites and mafic-ultramafic complexes range from-6.68 to 1.11 and-1.81 to 6.29, with zircon model ages of 1 812–1 319 Ma(TDM2) and 1 087–769 Ma(TDM1), respectively. Hf isotopic data indicate that primary magmas of the monzogranites are originated from partial melting of ancient lower crust during the Paleo-Mesoproterozoic, with a juvenile-crust component. Primitive magmas of the mafic-ultramafic complexes are likely originated from a depleted-mantle source modified by slab-derived fluids and contaminated by crustal components. Geochemical data and the geological setting indicate that Devonian intrusions in the Maxingdawannan area are related to northward subduction of the ProtoTethys oceanic lithosphere.

关键词： geochronology geochemistry Hf isotopes Maxingdawannan Proto-Tethys Ocean

Zircon SHRIMP U-Pb Dating and Geochemical Characteristics of Late Variscan Granites of the Daitongshan Copper Deposit and Lamahanshan Polymetallic-Silver Deposit, Southern Daxing'anling, China

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Journal of Earth Science 2013年第5期24卷 772-795页

作者：周振华李泊洋王挨顺武新丽欧阳荷根冯佳睿 MRL Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological Sciences No. 10 institute of geological exploration Inner Mongolia Bureau of Geology & Mineral Resources geological Survey institute of Inner Mongolia School of Earth Science and Mineral Resources China University of Geosciences Research institute of Petroleum exploration and Development PetroChina

Daxing＇anling （大兴安岭） area is one of the regions that Phanerozoic granites are extremely developed in NW China. At present, the Hercynian granitoid research lags behind the Mesozoic granitoid research. In this article, we have taken systematic petrochemistry and geochronology researches on the Hercynian granitoids in Daitongshan （代铜山） copper deposit and Lamahanshan （喇嘛罕山） silver poly- metallic deposit, which were located at southern section of Daxing＇anling metallogenic belt. Zircon SHRIMP U-Pb dating results show that, the granite aplites in Daitongshan and the gneissic granites inLamahanshan were formed at （265±5）-（268±9） Ma and （252±2）-（252.6±3.4） Ma, respectively, which were both the products of late Herynian tectonic-magmatic events. Samples from Lama- hanshan are characterized by high SiO2 （69.72 wt.%-74.65 wt.%）, high potassium （3.53 wt.%-4.55 wt.%） and low P205 （0.03 wt.%0.12 wt.%）, aluminum saturation index （A/CNK） range from 0.95 to 0.98, Rb, Nd and K are en- riched, whereas the elements such as Nb, Ta, P and Ti are depleted, which belong to I-type grani- toids. Characteristics of samples from Daitong- shan are similar to H-type granitoids. The magmasource may be mostly originated from the lithospheric mantle component which were transformated or affected by the subduction components, and its formation may be closely related with the subduction and orogenesis of the Paleo-Asian Ocean.

关键词： SHRIMP U-Pb dating geochemistry Variscan Daitongshan copper deposit Lamahan-shan silver polymetallic deposit Daxing'anling.

Anomaly Models of Spatial Structures for Copper-Molybdenum Ore Deposits and their Application

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 843-857页

作者： MA Shengming ZHU Lixin LIU Chongmin XI Mingjie TANG Shixin institute of Geophysical and Geochemical exploration CAGS Chinese Academy of geological Sciences

This paper discusses the enrichment and depletion regularities for porphyry coppermolybdenum ore deposits in different regions and varied deposit genetic types in the same area, taking three porphyry copper-molybdenum ore deposits （i.e., the Chengmenshan in Jiangxi, Wunugetushan in Inner Mongolia, Baishantang in Gansu） and two copper deposits in Gansu Province （the Huitongshan skarn deposit and Gongpoquan composite deposit） as case studies. The results show that porphyry Cu-Mo deposits or skarn copper deposits include both enrichment of the ore-forming elements and associated elements, and depletion of some lithophile dispersed elements, rare earth elements （REE） and some major elements. And the depleted elements vary with deposits, having generality and their own features. On a deposit scale, the positive anomalies of enriched elements and negative anomalies of depleted elements follow in a sequence to comprise regular anomaly models of spatial structures. The exploration in the Tongchang deposit in Jiangxi and Huitongshan deposit in Gansu suggests that anomaly models play a key role in the identification of mineral occurrences and deposits compared to one single enriched element anomaly. And the anomaly models exert a critical effect on the optimization of prospecting targets and their potential evaluation.

关键词： copper-molybdenum deposits enrichment and depletion anomaly models of spatial structures case studies

The First Discovery of Eosestheria in Eastern Liaoning,China

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Acta Geologica Sinica(English Edition) 2019年第2期93卷 479-480页

作者： WU Zijie WANG Haipeng GAO Fuliang ZHANG Guoren WANG Mincheng LUO Niangang Liaoning Provincial institute of geological exploration Co. Ltd geological and Mineral Survey institute of Liaoning Provincial

Objective The Jehol biota refers to a flora and fauna that thrived in the Early Cretaceous (Shao Tiequan et al., 2017), and Eosestheria is an important component of the Jehol biota and is also an important link in the... 详细信息

关键词： Discovery Eosestheria Eastern Liaoning

Geochemical analysis of marine sediments using fused glass disc by X-ray fluorescence spectrometry

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Chinese Journal of Oceanology and Limnology 2008年第4期26卷 475-479页

作者：夏宁张勤姚德李国会 Qingdao institute of Marine Geology Chinese Geological Survey institute of Geophysical and Geochemical exploration Chinese Academy of Geological Sciences institute of Environmental Science and Technology Shandong Umversity of Technology institute of Geophysical and Geochemical exploration Chinese Academy of geological Sciences

A method was developed for content determination of Na, Mg, A1, Si, P,S, C1, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Nb, Zr, Y, Sr, Rb, Ba, La and Ce etc. covering 26 major, minor, and trace elements in marine sediment samples using fused glass disc by X-ray Fluorescence spectrometry. Calibration was made using marine sediment certified reference materials and the synthetic standard samples prepared by mixing several marine sediments with stream sediment and carbonate standard samples in different proportions. The matrix effect was corrected using theoretical alpha coefficients, experience coefficients and the scattered radiation as the internal standard （for the trace elements）. The accuracy of the method was evaluated by analysis of certified reference materials GBW07314, GBW07334 and GSMS6. The results are in good agreement with the certified values of the standards with RSD less than 2.60%, except for Y, Cr, Ga, Ce, La, Nb, Rb, and V with RSD less than 9.0% （n=12）.

关键词： marine sediment X-ray fluorescence spectrometry geochemical analysis multi-element analysis

Geochemical Features and Metallogenic Prediction of the Caixiashan-Weiquan Area in the East Tianshan Region

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Acta Geologica Sinica(English Edition) 2012年第4期86卷 885-893页

作者： LU Lu ZHU Lixin XIAO Keyan MA Shengming YIN Jiangning XU Mingzuan Chinese Academy of geological Sciences institute of Mineral Resources Chinese Academy of Geological Sciences institute of Geophysical and Geochemical exploration CAGS Jiangsu Provincial institute of geological Prospecting Techniques

The Caixiashan-Weiquan area is an important ore concentration area in the eastern Tianshan metallogenic belt. Firstly, this paper studies geochemical features of 1564 samples of 1：200000 stream sediments of the Matoutan mapsheet, where the Caixiashan and Weiquan deposits are located. Processing, analysis and explanation of exploration geochemical data play an important role in the procedure of finding the ore, which are related to whether the measured elements content of geochemical samples can effectively guide the work of mineral exploration. As a highly nonlinear dynamical system, the neural network is more analogous to the human brains in terms of principles and features compared with conventional geochemical approaches. It can adapt itself to the environment, sum up laws, complete pattern recognition. Secondly, the authors used the Kohonen neural network to classify all samples based on 10 mineralization elements of stream sediment samples in order to determine possible mineral ores, reduce the scope of ore targets and study indicator elements of the ninth group of samples, which is the mostly closest to the deposit. The results show that the neural network can delineate metallogenic prospective areas and is effective in the discovery of deep geochemical information.

关键词： Regional exploration geochemistry Pb-Zn deposits neural network metallogenic prediction

Numerical study on the deformation of soil stratum and vertical wells with gas hydrate dissociation

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Acta Mechanica Sinica 2016年第5期32卷 905-914页

作者： Xudong Chen Xuhui Zhang Xiaobing Lu Wei Wei Yaohong Shi institute of Mechanics Chinese Academy of Sciences Research institute of Petroleum exploration and Development-Langfang Marine Environmental and Engineering geological Survey Guangzhou Marine Geological Survey

Gas hydrate（GH） dissociates owing to thermal injection or pressure reduction from the well in gas/oil or GH exploitation. GH dissociation leads to, for example, decreases in soil strength, engineering failures such as wellbore instabilities, and marine landslides. The FLAC3 D software was used to analyze the deformation of the soil stratum and vertical wells with GH dissociation. The effects of Young＇s modulus, internal friction angle, cohesion of the GH layer after dissociation, and the thickness of the GH layer on the deformation of soils were studied. It is shown that the maximum displacement in the whole soil stratum occurs at the interface between the GH layer and the overlayer. The deformation of the soil stratum and wells increases with decreases in the modulus, internal friction angle, and cohesion after GH dissociation. The increase in thickness of the GH layer enlarges the deformation of the soil stratum and wells with GH dissociation. The hydrostatic pressure increases the settlement of the soil stratum, while constraining horizontal displacement. The interaction between two wells becomes significant when the affected zone around each well exceeds half the length of the GH dissociation zone.

关键词： Gas hydrate Dissociation FLAC3D Soil stratum Well