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GEOCHEMICAL EVIDENCE FOR TWO TYPES OF BASALT IN THE HONGLIUGOU OPHIOLITE MELANGE IN THE ALTYN FAULT BELT, CHINA

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Scientia Geologica Sinica 2001年第2期 133-142页

作者： Wu Jun, Lan Chaoli, Li Jiliang, and Yu Liangjun Laboratory of Lithosphere Tectonic Evolution, institute of Geology and Geophysics, chinese academy of sciences, beijing, 100029 Wang Yitian institute of Geology, chinese academy of geological sciences, Beij

This paper further provides geochemical evidence for the Hongliugou ophiolite melange. The two types of basalt (MORB and OIB) indicates that an ocean, perhaps a large one, once existed in this region during Early Paleozoic. Their coexistence is clearly the result of late tectonic migrations. Considering a similar assemblage of MORB and OIB in north Qilian Mountains, the strike-slip distance along the Altun fault belt will be estimated possibly.

关键词： OIB meta GEOCHEMICAL EVIDENCE FOR TWO TYPES OF BASALT IN THE HONGLIUGOU OPHIOLITE MELANGE IN THE ALTYN FAULT BELT CHINA

The Ashele VMS-type Cu-Zn Deposit in Xinjiang,NW China Formed in a Rifted Arc Setting

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The Ashele VMS-type Cu-Zn Deposit in Xinjiang,NW China Forme...

PTtD Path and Fluid Evolution of HighPressure Eclogites from the Dabie Mountains,Central East China

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Bo WAN,Lianchang zhang and Peng XIANG Key Laboratory of mineral Resources,institute of Geology and Geophysics,chinese academy of sciences,beijing,China

The Ashele Cu-Zn deposit is a typical VMS deposit in chinese Altay located in the southern margin of the Altaid *** deposit occurred in the polyphase fold system,and the main orebody is located at the hinge of the *** orebodies show lenticular form,and are stratabound by a suite of early to middle Devonian bimodal volcanic *** hosting basalt is low K tholeiite and characterized with high Mg,Fe,Ca and low K,*** basalts show flat REE pattern with Ce negative anomaly(Ce/Ce 0.73-0.76).Niobium,Ta, Zr,Hf are depleted and Rb,Ba,Th,U,Sr,Pb are enriched with respect to the *** the Sr and Nd isotopes show depleted properties,while the(Sr/Sr) and theε(t)range from 0.70469 to 0.70488 and 4.6 to 5.3,*** geochemical and isotopic data from the hosting basalt show that it originates from an island arc *** also report the S isotope data from the massive orebody,andδS‰change from 1.8‰to 5.6‰.The S isotope data provide evidence that the sulfur originates from a mixing source between magma and seawater *** propose that the mafic magma provides the ore-forming metal and some percentage of sulfur,while it also acts as a heat engine which makes the fluids leach the metal from the underlying volcanic *** the geological characteristics of the Ashele and geochemical data,and comparing with other Cu-Zn VMS deposits in the world,we propose that Ashele formed in *** arc setting.

关键词： Altaid orogen Ashele Cu-Zn VMS deposit island arc

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Continental Dynamics 1999年第1期 44-52页

作者： zhang Zeming institute of Geology, chinese academy of geological sciences , beijing 100037, China WEI Bize HAN Yujing YOU Zhendong China University of Geosciences, Wuhan 430001, China

In the Dabie high pressure (HP) and ultrahigh pressure (UHP) metamorphic belts, eclogites can be divided into two types, HP eclogites (or cold eclogite) and UHP eclogites. HP eclogites occur in the southern Dabie Mountains and are characterized by the presence of glaucophane. The primary mineral assemblage of the eclogites is garnet, omphacite, phengite, epidote, glaucophane, quartz, zircon and rutile. Garnet contains abundant mineral inclusions, and exhibits apparent compositional zoning with dramatic increases in MgO and decreases in MnO from core to rim. The PTtD path indicates that supracrustal rocks were metamorphosed and deformed from epidote amphibolite to eclogite facies by subduction and collision, then uplifted to the upper crust by thrust faulting in a continuous plate convergence and reworked by retrograde metamorphism of epidote amphibolite facies and by ductile deformation. The HP metamorphic rocks were uplifted to the surface, and modified by greenschist retrograde metamorphism and ductile to brittle deformation in an extensional environment. Fluid inclusions, melt inclusions and fluid bearing minerals indicate that fluid melt rock interaction was widespread in the eclogites. Partial melting occurred during the HP metamorphism, but the migration of melt was limited, and thus magma activity was very limited. Secondary fluid inclusions are abundant in the eclogites of the Dabie Mountains. They are mainly H 2O and CO 2 rich, and halite bearing multiphase fluid inclusions. Primary fluid inclusions have not been found, possibly because rapid uplift caused decrepitation of high density inclusions.

关键词： HP eclogite PTtD path fluid and melt inclusions Dabie Mountains

RESEARCH ON THE COMPOSITION OF mineral MELT INCLUSIONS IN VOLCANIC ROCK SERIES IN THE GREAT WALL STATION AREA, KING GEORGE ISLAND, ANTARCTICA

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chinese Science Bulletin 1988年第23期33卷 1962-1964页

作者：王碧香张元奇 institute of Geology Chinese Academy of Geological Sciences Beijing

Ⅰ. INTRODUCTION The Great Wall Station area is located in the Fildes Peninsula, King George Island. The strata are composed mainly of basaltic and basah-andesitic lavas, pyroclastic rocks and pyroclastic-sedimentary rocks. This volcanic rock series shows the characteristics of typical island-arc volcanic rocks. From below upwards five rock units may be distinguished: (Ⅰ) the Jasper Hill Member, (Ⅱ)the Agate Beach Mem-

关键词： Antarctica basalt composition of mineral melt inclusions

Heat flow pattern,base of methane hydrates stability zones and BSRs in Shenhu Area,northern South China Sea

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Acta Oceanologica Sinica 2011年第1期30卷 59-67页

作者： zhang Yi HE Lijuan WANG Jiyang XU Xing SHA Zhibing GONG Yuehua WANG Hongbing LIANG Jinqiang institute of Geology and Geophysics Chinese Academy of Science Beijing 100029 China Graduate University of the chinese academy of sciences Beijing 100049 China Guangzhou Marine geological Survey Guangzhou Guangdong 510760 China

Using the collected 433 heat flow values, we estimated the bases of methane hydrate stability zone （BHSZ）, in northern South China Sea （NSCS）. Through comparing BHSZs with the depths of bottom simulating reflectors （BSRs）, in Shenhu Area （SA）, we found that there are big differences between them. In the north of SA, where the water depth is shallow, many slumps developed and the sedimentation rate is high, it appears great negative difference （as large as -192%）. However, to the southeast of SA, where the water depth is deeper, sedimentation rate is relatively low and uplift basement topography exists, it changes to positive difference （as large as ＋45%）. The differences change so great, which haven＇t been observed in other places of the world. After considering the errors from the process of heat flow measurement, the BSR depth, the relationship of thermal conductivity with the sediments depth, and the fluid flow activities, we conclude that the difference should be not caused by these errors. Such big disagreement may be due to the misunderstanding of BSR. The deviant ＂BSRs＂ could represent the paleo-BSRs or just gas-bearing sediment layers, such as unconformities or the specific strata where have different permeability, which are not hydraterelated BSRs.

关键词： methane hydrate BSR base of methane hydrate stability zone slump heat flow

Geology and Geochemistry of K-feldspar Veins in Lamprophyre at the Zhenyuan Gold Deposit,Yunnan,Southwest China:Implications for Gold mineralization

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 104-116页

作者： zhang Huichao CHAI Peng zhang Hongrui ZHOU Limin HOU Zengqian Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210024China National Research Center for Geoanalysis Beijing 100037China

Lamprophyres typically appear in hydrothermal gold *** relationship between lamprophyres and gold deposits is investigated *** researchers suggest that the emplacement of lamprophyres triggers gold mineralization,whereas others hypothesize that the formation of lamprophyres increases the fertility of mantle sources and ore-forming fluids.K-feldspar veins,with ages between those of lamprophyres and gold deposits,appear in lamprophyres in ***,K-feldspar veins are ideal for investigating the relationship between lamprophyres and gold *** in K-feldspar veins has lower Mg#,Ni,and Cr contents and higher TiO2,Li,Ba,Sr,Sc,Zr,Nb,and Cs contents than phlogopite in *** in-situ Sr isotopic values of apatites(0.7063–0.7066)in K-feldspar veins are within the range for apatites(0.7064–0.7078)from *** large-ion lithophile element concentrations and low Nb and Ta concentrations in phlogopite from lamprophyres,in addition to high(87Sr/86Sr)i values of apatite(0.7064–0.7078),indicate that the magma parental to these phlogopite and apatite crystals is derived from an enriched *** veins are genetically correlated with lamprophyres,whereas sulfide mineral assemblage and trace element compositions of pyrite in K-feldspar veins suggest that K-feldspar veins in lamprophyres are not directly related to gold mineralization of the Zhenyuan deposit.

关键词： lamprophyre K-feldspar vein apatite Sr isotope gold Zhenyuan deposit Yunnan

国内外科学数据共享平台安全管理策略及典型做法研究

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中国科技论坛 2024年第4期 179-188页

作者：张贵兰王健潘云涛杨代庆中国科学技术信息研究所北京100038 中国农业科学院农业信息研究所北京100083

在数字化浪潮和开放科学持续发展的大背景下,科学数据的规模总量与综合价值将长期处于增长通道,数据安全的监管力度也将持续提升,这些因素在客观上决定了科学数据安全工作的重要性和紧迫性。本文围绕如何有效提升中国科学数据安全管理... 详细信息

在数字化浪潮和开放科学持续发展的大背景下,科学数据的规模总量与综合价值将长期处于增长通道,数据安全的监管力度也将持续提升,这些因素在客观上决定了科学数据安全工作的重要性和紧迫性。本文围绕如何有效提升中国科学数据安全管理能力的必然需求,以科学数据共享生态系统为基本出发点,通过梳理ICPSR、UKDA、国家地球系统科学数据中心等国内外代表性科学数据共享平台的相关经验和典型做法,初步勾勒科学数据安全治理整体样貌,重点描述了科学数据共享平台数据安全管理策略的细节,总结了科学数据安全管理的举措,并根据安全治理水平,将科学数据共享平台分为深度安全管理、中度安全管理与浅度安全管理三个类型。通过对比国内外科学数据共享平台的安全管理策略,为中国科学数据安全管理提供经验借鉴。

关键词：科学数据科学数据共享平台安全管理典型举措

Microstructures, Fabrics, and Seismic Properties of Mylonitic Amphibolites: Implications for Strain Localization in a Thickening Anisotropic Middle Crust of the North China Craton

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Journal of Earth Science 2024年第3期35卷 769-785页

作者： Siqi Liu Bo zhang Jinjiang zhang Jian zhang Lei Guo Tao Wang Baoyou Hang Xiaorong Li Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China Department of Earth sciences The University of Hong KongHong KongChina institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

Strain localization processes in the continental crust generate faults and ductile shear zones over a broad range of scales affecting the long-term lithosphere deformation and the mechanical response of faults during the seismic *** anisotropy originated within the continental crust can be applied to deduce the kinematics and structures within orogens and is widely attributed to regionally aligned minerals,e.g.,***,naturally deformed rocks commonly show various structural layers(e.g.,strain localization layers).It is necessary to reveal how both varying amphibole contents and fabrics in the structural layers of strain localization impact seismic property and its interpretations in terms of *** present microstructures,petrofabrics,and calculate seismic properties of deformed amphibolite with the microstructures ranging from mylonite to *** transition from mylonite to ultramylonite is accompanied by a slight decrease of amphibole grain size,a disintegration of amphibole and plagioclase aggregates,and amphibole aspect ratio increase(from 1.68 to 2.23),concomitant with the precipitation of feldspar and/or quartz between amphibole *** intensities of amphibole crystallographic preferred orientations(CPOs)show a progressively increasing trend from mylonitic layers to homogeneous ultramylonitic layers,as indicated by the JAm index increasing from 1.9–4.0 for the mylonitic layers and 4.0–4.8 for the transition layer,to 5.1–6.9 for the ultramylonitic *** CPO patterns are nearly random for plagioclase and *** amphibole aggregates in the amphibolitic mylonite deform by diffusion,mechanical rotation,and weak dislocation creep,and develop CPOs *** polymineralic matrix(such as quartz and plagioclase)of the mylonite and the ultramylonite deform dominantly by dissolution-precipitation,combined with weak dislocation *** mean P and S wave velocities are estimated to be 6.3 and 3.5 km/

关键词： amphibolitic mylonite microstructures petrofabrics seismic property middle crust rheology tectonics.

Features of inclusions in the Funiushan gold deposits of Central China and its implications for prospecting

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chinese Science Bulletin 1999年第S2期44卷 15-16页

作者： zhang Zhengwei~1, ZHU Bingquan~1 and DENG Jun~2 1. Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, China 2. China University of Geoscience, beijing 100083, China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China China University of Geoscience Beijing 100083 China

GOLD mineralization popularly occurs in Funiushan area. Based on the studies on more than 40 gold deposits or ore spots, it is shown that most of them are small in scale except the Pengou gold deposit, whichcan be developed into a medium one. The Pengou is a gold deposit of medium-low temperature hydrothermal type. 1 geological setting The Funiushan gold mineralization zone lying in the contiguous region of Nanzhao, Fangcheng andLushan Counties, Henan Province, is stituated on the tectonic and geochemical boundary between theNorth China block and Qinling Orogenic belt, and transverses the two first-grade tectonic units. Thehost rocks are mainly the strata of Xionger group （Pt2 ） and the Funiushan granitic batholith. The Penggougold deposit is just located on the large-scale fault of Xiatang-Guihe. A series of metamorphic rocks ofXionger Group outcroped in the north of the deposit. 2 The features of deposit The ore bodies mostly appear in thick plate with sag-and-swell variation. The gold-bearing alterationzone from upper to lower layers can be divided as granite→ pyritization and phyllic alteration→ alteredgranitic porphyry→quartz vein→pyritization and phyllic alteration→cataclastic granite with phyllic alteration, i. e. the upper and lower gold-bearing layers can be separated by the altered granite. The ore

关键词： gold deposit inclusion geochemistry Funiushan.