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Isotopic Geochronological Evidence for the Caledonian Xiongdian Eclogite in the Northwestern Dabie Mountains,china

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 455-465页

作者： Jian PingYichang institute of geology and mineral {3.. CAGS, Yichang City,Hubei Province 443.03.ang Weiran china University of Geosciences, Wuhan, HubeiLi Zhichang Yichang institute of geology and mineral {3., CAGS, Yichang, HubeiZhou Huifang tianjin Instutite of geology and mineral {3., CAGS, tianjin Zhu Xiling

A typical HP/MT (high pressure/medium temperature) eclogite from Xiongdian, northwestern Dabie Mountains, has been geochronologically studied using the single-zircon U-Pb, 40Ar-3.Ar and Sm-Nd methods. Prismatic zircons occurring as inclusions within garnets define a minimum crystallization age of 3.9.5±1.6 Ma. 40Ar-3.Ar dating on amphibole gives a plateau *** 3.9.2 ± 4 Ma, which is interpreted as a retrogression age of amphibolite facies. This integrated study enables us to conclude that the age of high-pressure metamorphism is older than 3.9.5 ± 1.6 Ma, suggesting Caledonian collision between the North china and Yangtze plates. Round zircon within the aggregate of quartz and muscovite gives a concordant age of 3.1± 2 Ma, reflecting a later retrogression event. An age profile of post-eclogite metamorphism is documented, including amphibolite facies metamorphism at 3.9.2 Ma shortly after eclogitization and later retrogressive metamorphism at 3.1 Ma. Sm-Nd mineral isochron of garnet+omphacite gives an unreasonable age of 544 ± 23.Ma. which is quite older than that of prismatic zircon and may be attributed to isotopic disturbance by retrogression.

关键词： Caledonian collision eclogites geochronlogy Northwestern Dabie area Xiongdian Henan

γ-PHASE IN WC-Co CEMENTED CARBIDES

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中国有色金属学会会刊：英文版 1993年第2期3卷 51-57页

作者： Liu,Shourong tianjin institute of Hard Alloy,tianjin 3.0222,{3.

The allotropic transformation process of the γ-phase in WC-Co cemented carbides has been *** of γ-grain and the γ-domain have been proposed forward:The γ-domain is the residual FCC-typeβ-Co grain that failed to transform when cooling alloy sample and γ-base is the HCP-type x-Co transformedmainly by means of diffusion,the outline of the γ-grain is consistent with the newly fromed β-Co grain formedat high *** quantity and distribution of γ-grain domain are related to the cooling rate after sinter-ing and influence the alloys properties.

关键词： WC-Co cemented carbides γ-grain γ-domain

Geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

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Science china Earth Sciences 2006年第9期49卷 904-914页

作者： WANG Xiaorui1, GAO Shan1,2, LIU Xiaoming1, YUAN Honglin1, HU Zhaochu1, ZHANG Hong1,3.& WANG Xuance4 1. State Key Laboratory of Continental Dynamics, Department of geology, Northwest University, Xi`an 710069, china 2. State Key Laboratory of Geological Processes and mineral {3., china University of Geosciences, Wuhan 43.074, china 3. Shenyang institute of geology and mineral {3., Shenyang 11003., china 4. Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an China State Key Laboratory of Geological Processes and mineral resources China University of Geosciences Wuhan China Shenyang institute of geology and mineral {3. Shenyang China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2 = 52.82-59.3. wt%, Al_2O_3.14.15-16.3.wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03.1.88 μg/g) and Y(12-20 μg/g) and high Sr (620-13.3.μg/g) and Sr/Y(3.-88), withhigh La_N/Yb_N ratio (10-25). They share similar major and trace element characteristics to volcanicrocks from the Xinglonggou Formation except their lower Nd isotope ratios (^(143.Nd/^(144)Nd(13.Ma) = 0.5118-0.5119, ε_(Nd) (13.Ma) = -11.6-13.8, ^(87)Sr/^(86)Sr (13. Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North china craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the Xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal material in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 120 to 13. Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2 for samples with SiO_2 > 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North china Craton, delamination.

β→α Transformation of γ-Phase in Sintered WC-Co Cemented Carbides

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Journal of Materials Science & Technology 1996年第5期12卷 398-400页

作者： Shourong LIU (tianjin institute of Hard Alloy tianjin 3.0222,{3.)Yi LIU (Shandong University Jinan 250100,{3.) tianjin institute of Hard Alloy Tianjin 300222 China Shandong University Jinan 250100 China

Varying the morphology and the structure of γ-phase (Co-base Co-W-C solid solution) by means of altering the cooling rate and the preparing method of liquid sintered WC-Co cemented carbides samples, the mechanism of fcc→hcp transformation of γ-phase in WC-Co alloy has been explored. The results show that, the cooling rate is an important affecting factor on fcc→hcp transformation of γ-phase and the fcc→hcp transformation is mainly a diffusive type when cooling WC-Co samples above room temperature

关键词： WC Co Phase in Sintered WC-Co Cemented Carbides Transformation of

Preliminary Study of the Characteristics and Genesis of Arsenate minerals in the Oxidized Zone of the Debao Skarn-Type Cu-Sn Ore Deposit in Guangxi

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 187-194页

作者： Li Yi Lai Lairen institute of geology and mineral {3.,china National Nonferrous Metals Industry Corporation Zhang Zhongmin institute of geology and mineral {3. China National Nonferrous Metals Industry Corporation

Through the study of the oxidized zone of the Debao skarn-type Cu-Sn deposit in Guangxi, the authorshave found 14 arsenate minerals, most of which are for the first time reported in china. They are mainly Cuarsenate minerals with subordinate Cu-Pb arsenate minerals and minor Fe-Pb-Ba varieties. Based on their paragenesis these minerals may be divided into the following series: (1) the clinoclasite-olivenite-cornwallite- cornubite- debaoite- copper silicarsenate association, (2) the scorodite- carminite- beudan-tite-bayldonite- duftite association, and (3. the scorodite-Ba-bearing pharmacosiderite- dussertite association. Arsenate minerals are formed generally in the oxidized zone of the sulfide-type deposits which lie in thewarm, humid and rainy torrid-subtropical zone with pH=6-8 and contain large amounts of arsenopyrite andcarbonate rocks.

关键词： Preliminary Study of the Characteristics and Genesis of Arsenate minerals in the Oxidized Zone of the Debao Skarn-Type Cu-Sn Ore Deposit in Guangxi Cu Sn

Minerogenetic Model for Two Types of Fluorite Deposits in Southeastern china

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 75-88页

作者： Li Changjiang Jiang Xuliang Zhejiang institute of geology and mineral {3., Hangzhou Liu Linqun Zhejiang institute of geology and mineral {3. Hangzhou

On the basis of the studies of field geology, strontium, hydrogen and oxygen isotopes and REEgeochemistry, coupled with the dating of mineralization, the authors suggest a minerogenetic model of circula-tion and drawing of Late Cretaceous geothermal waters for the fluorite deposits in southeastern china. Thismodel includes two types of mechanism: 1) the leaching-out and drawing through deep circulation of thegeothermal water, and 2) the leaching-out and drawing through shallow circulation of the water. The fluoritemineralization of Mesozoic volcanic rock terrain is related mainly to the former mechanism, with the mineraliz-ing material coming chiefly from the Precambrian metamorphic rocks of the basement underlying the hostrocks; while that of Yanshanian granite terrain is associated with the latter mechanism, with the mineralizingmaterial derived primarily from the host granites and sedimentary rocks.

关键词： Minerogenetic Model for Two Types of Fluorite Deposits in Southeastern china

DISCUSSION ON THE NAMING OF QUATERNARY TRANSGRESSIONS IN WEST-SOUTHERN COAST PLAIN OF BOHAI SEA

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Acta Oceanologica Sinica 1987年第1期6卷 104-115页

作者：王强李凤林李玉德高秀林 tianjin institute of geology and {3. resources tianjin geology and mineral resources Bureau Shandong Province Dezhou Department of Geography tianjin Teachers University

Based on micropalaeontological information of over 150 drill holes, this paper discusses the problem on the naming of Quaternary transgressions in the west-southern coast plain of Bohai Sea. We consider that palaeotide and sedimentation have a great influence on the distribution of micropalaeontological fossils. In view of the present technical level, it is necessary for transgression sequence to be established under the following conditions: full evidence of fossils; clear climate; and stable sedimentary beds. In establishing a transgression, its contents of time and phase concept must be proposed, and its biofacies, sedimentary facies and palaeoclimatology must be analysed synthetically.

关键词： DISCUSSION ON THE NAMING OF QUATERNARY TRANSGRESSIONS IN WEST-SOUTHERN COAST PLAIN OF BOHAI SEA

Second mode unstable disturbance measurement of hypersonic boundary layer on cone by wavelet transform

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Acta Mechanica Sinica 2011年第4期27卷 488-493页

作者： Jian Han.Nan Jiang.Yan Tian Department of Mathematics,tianjin University,3.0072 tianjin,china Department of Mechanics,tianjin University,3.0072 tianjin,china tianjin Key Laboratory of Modern Engineering Mechanics,3.0072 tianjin,china State Key Laboratory of Nonlinear Mechanics,institute of Mechanics,Chinese Academy of Sciences,100190 Beijing,china Department of Mathematics Tianjin University Tianjin China Department of Mechanics Tianjin University Tianjin China tianjin Key Laboratory of Modern Engineering Mechanics Tianjin China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China

Experimental investigation of hypersonic boundary layer instability on a cone is performed at Mach number 6 in a hypersonic wind tunnel. Time series signals of instantaneous fluctuating surface-thermal-flux are measured by Pt-thin-film thermocouple temperature sensors mounted at 28 stations on the cone surface in the streamwise direction to investigate the development of the unstable disturbance. Wavelet transform is employed as a mathematical tool to obtain the multi-scale characteristics of fluctuating surfacethermal-flux both in the temporal and spectrum space. The conditional sampling algorithm using wavelet coefficient as an index is put forward to extract the unstable disturbance waveform from the fluctuating surface-thermal-flux *** generic waveform for the second mode unstable disturbance is obtained by a phase-averaging technique. The development of the unstable disturbance in the streamwise direction is assessed both in the temporal and spectrum space. Our study shows that the local unstable disturbance detection method based on wavelet transformation offers an alternative powerful tool in studying the hypersonic unstable mode of laminar-turbulent transition. It is demonstrated that, at hypersonic speeds, the dominant flow instability is the second mode, which governs the course of laminar-turbulent transition of sharp cone boundary layer.

关键词： Hypersonic boundary layer. Sharp cone Insta-bility Wavelet transform

Whole fossil plants of Ephedra and their implications on the morphology,ecology and evolution of Ephedraceae (Gnetales)

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Chinese Science Bulletin 2010年第15期55卷 1511-1519页

作者： WANG Xin 1,2 & ZHENG ShaoLin 3.1 Nanjing institute of geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,china 2 Fairy Lake Botanical Garden,Shenzhen 518004,china 3.Shenyang institute of geology and mineral resources,Shenyang 11003.,china Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China Fairy Lake Botanical Garden Shenzhen 518004 China Shenyang institute of geology and mineral {3. Shenyang 110034 China

Although there are many reports of fossil Ephedraceae,whole plant fossil record remains *** to a lack of trust on partially preserved fossil materials,scholars working on molecular clock proposed a recent origin of Ephedra and cast doubt on the earlier origin time of *** better the understanding on this interesting group,here we report whole plants of Ephedra hongtaoi ***.(Ephedraceae,Gnetales) from the Yixian Formation (Early Cretaceous) in western Liaoning,*** whole plants of Ephedra demonstrate clearly the characters of Ephedra,including shrubby growth habit,decussate branching pattern,and terminal ovuliferous unit with micropylar *** whole-plant preservation of the fossils provides more convincing fossil evidence of Early Cretaceous Ephedra,helps to resolve the controversy over the origin time of Ephedra,and sheds light on the whole plant morphology,growth habit,ecology and evolution of Ephedraceae.

关键词：化石植物生态学麻黄形态学进化材料保存早白垩世生长习性