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Geochemistry of Sedimentation and Diagenesis in Qixia Formation (Early Permian) of Badong, Hubei Province, China: Implications for T-R Cycle Interpretation

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Journal of Earth Science 1999年第2期18卷 56-62页

作者： Yan Jiaxin Zhao Laishi Faculty of Earth Sciences, China university of Geosciences, Wuhan 4.0074.Fang Nianqiao Department of geology and Mineral Resources, China university of Geosciences, Beijing 100083

Combined with sedimentary observation and mineralogical research on a type of drusy celestite of early diagenesis in origin, this geochemical study on the Qixia Formation at the Shuibuya Section, Badong County, Hubei Province of south China evaluates the contribution of sedimentation and diagenesis to the mass fractions of CaO, Al 2. 3, MgO, SiO 2. Fe 2. 3, Na 2., K 2., mn, Sr, P and Ba in the carbonates. The Sr, initially released from the stabilization of carbonate calcium mineral, precipitated with sulfate ion as celestite in early diagenetic environment, where sulfate reduction was the minimum. Then it redistributed in burial diagenetic environment, where celestite was replaced by calcite. The fractions of the MgO and SiO 2.in the carbonates were mainly modified by the early dolomitization and silicification respectively. That of the Na 2. was overprinted by the burial diagenesis. Multivariate statistical analysis on data of sixty bulk rocks indicates that the mass fractions of the Al 2. 3, K 2., Fe 2. 3, mn, CaO, P and Ba were affiliated with the sedimentary factor despite the obvious decrease of CaO during early dolomitization and silicification. Among them, the Al 2. 3 and K 2. mainly represent the detrital components. In addition, a dysaerobic sedimentary background was confirmed by trace element measurement and information derived from the formation of the celestite. This genetic discrimination facilitates the interpretation of the transgressive regressive (T R) cycle and specialities featured this unusual carbonate unit.

关键词： sedimentation diagenesis celestite geochemistry T R cycle.

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Elemental and isotopic compositions of the hydrothermal sulfide on the East Pacific Rise near 13°N

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Science China Earth Sciences 2010年第2期53卷 253-266页

作者： ZENG ZhiGang1,CHEN DaiGeng1,2.YIN XueBo1,WANG XiaoYuan1,ZHANG GuoLiang1,2.& WANG XiaoMei1,2.1 Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine geology and Environment,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 2.6071,China 2.Graduate School of Chinese Academy of Sciences,Beijing 10004.,China Seafloor Hydrothermal Activity Laboratory of the Key Laboratory of Marine geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School of Chinese Academy of Sciences Beijing China

The mineralogical,elemental,and isotopic characteristics of a hydrothermal sulfide sample from one dredge station (12.4..30’N,103°54.4.’W,water depth 2.55 m) on the East Pacific Rise near 13°N were *** hydrothermal sulfide was composed mainly of sphalerite,chalcopyrite,and pyrite and was a Zn-rich sulfide;in layer ep-s-1,goethite formed by secondary oxidation was *** concentrations of rare elements,such as Li (0.15×10-6-0.30×10-6),Be (0.01×10-6-0.05×10-6),Zr (73.8×10-9-134.×10-9),Nb (8.14.10-9-64.7×10-9),Hf (2.54.10-9-2..0×10-9),and Ta (0.2.3×10-9-1.2.×10-9),were far lower in the hydrothermal sulfide than in the ocean crust,whereas the content of Au was higher and the contents of Co,Ni,Sr,Cs,Ba,Bi,and U were *** correlations between Zn and Cr,Cd and Ga,Cu and P,P and In (R2.> 0.8) were positive,whereas those between Zn and Fe,Cu,and Ba (R2.> 0.8) were distinctly *** low-temperature mineral assemblages to high-temperature mineral assemblages,the spatial distributions of dispersive and rare elements (***,Li,Cs) in the hydrothermal sulfide displayed corresponding *** variations observed in some elements (e.g.,Cd,Cs,P) are controlled by Zn,Fe,and Cu sulfides,*** weathering accounts for the enrichment of V,mn,and rare earth elements (REE) in the henna sulfide-oxidation layer that bears the secondary oxide mineral,leading to identical REE patterns for this layer (ep-s-1) and *** weathering also distinctly affects the correlations between the element ratios of the hydrothermal *** high-temperature mineral assemblages to low-temperature mineral assemblages,Fe content and δ 34. value of the hydrothermal sulfide increase gradually,and Zn content and lead isotopic ratios decrease gradually on the contrary,which indicate the influences of seawater on elements and the sulfur and lead isotopic compositions enhance gradually during the formation of hydrothermal sulfides.

关键词： variation element isotopic composition hydrothermal sulfide East Pacific Rise 13oN

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Cryptomelane(Kxmn(8-x)O(16)) Natural active octahedral molecular sieve(OMS-2.

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Chinese Science Bulletin 2003年第9期48卷 920-923页

作者： LU Anhuai, GAO Xiang, QIN Shan & WANG ChangqiuDepartment of geology, Peking university, Beijing 100871. China Correspondence should be addressed to Lu Anhuai (e-mail: ahlu@ ***) Department of geology Peking University Beijing 100871 China

The Xiangtan manganese deposit (XTM) used to be considered a supergene oxide manganese ore in South China. We reported a new identification of the naturally outcropping cryptomelane by examining the physical, chemical and structural features of the XTM supergene oxide manganese ore. The mnO2.content was over 90%, K2. more than 3%, and water from 2.2.-3.1% which is similar to one in zeolite. The cell parameters of the cryptomelane were given as a0 = 0.9974.nm, b0 = 0.2.63 nm, c0 = 0.9693 nm and β91.4.(. There was a larger pseduotetragonal tunnel in the natural cryptomelane that was formed by [mnO6] octahedral double chains with aperture of 0.4.2.0.4.6 nm2. filled with K cations resulting in some mn3+ substituting for mn4. to balance the negative charges of structure. The finding is important not only for prospecting manganese resources in South China, but also in application of octahedral molecular sieve of natural cryptomelane as that developed in the tetragonal molecular sieve of natural zeolite over the past century. The XTM cryptomelane (OMS-2. may be the real mineral of the active octahedral molecular sieve in nature.

关键词：隐钾锰矿天然活性分子筛 OMS-2 湘潭锰沉积物浅生矿床氧化物

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The Background Features and Formation of Chemical Elements of Groundwater in the Region of the Middle and Lower Reaches of the Yangtze River

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Acta Geologica Sinica(English Edition) 1997年第1期71卷 80-89页

作者： Zeng Zhaohua Institute of Environmental geology,Jiangxi Bureau of geology and Mineral Resources, Nanchang, Jiangxi Shang Ruoyun

The paper deals with the background features, formation and distribution of the chemical el-ements K, Na, Ca, Mg, Si, Fe, mn, Cr, Ni,V, Co, Ti, Mo, Cu, Pb, Zn, As, Hg, Cd, Be, Li, Sr, B,F, Cl, Br and I in the groundwater in the region of the middle and lower reaches of the YangtzeRiver and their relations to the composition of the water-bearing media, properties of the overly-ing rocks and soils, redox environment, and groundwater flow condition, mineralization and pHof groundwater.

关键词： lower-middle reaches of the Yangtze River groundwater chemical element background feature

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Hydrothermal alteration of chevkinite-(Ce) in the Shuiquangou syenitic intrusion,northern China

Hydrothermal alteration of chevkinite-(Ce) in the Shuiquango...

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中国科学院地质与地球物理研究所2.06学术年会

作者： Jiang,Neng Key Laboratory for Mineral Resources Research,Institute of geology and geophysics,Chinese Academy of Sciences,Beijing 10002.,China

A rare-earth iron titanosilicate mineral closely associated with amphibole was found in two altered syenite samples from the Shuiquangou syenitic *** on electron microprobe analyses,the mineral is chevkinite-(Ce).The mineral is altered and mantled by a corona of allanite(?)ilmenite(?)titanite(?)epidote(?)*** balance calculations reveal that the former chevkinite was replaced directly by an allanite and ilmenite association (allanite(?)ilmenite zone) in the inner part of the corona *** appears that during the replacement,Si and Ti were immobile,whereas Al,Fe,mn,Mg and Ca were externally supplied and a proportion of REE and Th were transferred out of the former *** released REE and Th become incorporated in allanite and titanite in the allanite(?)ilmenite(?)titanite mantle where allanite contains higher Nd,Sm and Y but lower La and Ce than that in the allanite(?)ilmenite zone,suggesting that redistribution of these elements took place and the mobility of Nd,Sm and Y is enhanced during hydrothermal alteration.

关键词： Chevkinite-(Ce) Corona system Hydrothermal alteration Mobilization

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Carbon and Strontium Isotopes of Late Palaeozoic Marine Carbonates in the Upper Yangtze Platform,Southwest China

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Acta Geologica Sinica(English Edition) 1997年第3期71卷 282-292页

作者： Huang Sijing and Zhou Shaohua State Key Laboratory of Oil and Gas Reservoir geology and Exploitation,Chengdu university of Technology, Chengdu, 610059, Sichuan, China Geological Institute, university of Copenhagen, Oster Voldgade 10,DK-1350 Copenhagen K,Denmark

2.8 marine carbonate samples were collected from seven sedimentary sections ofthe entire late Palaeozoic (Permian, Carboniferous and Devonian) in the Upper Yangtze Plat-form, southwest China. Based on the absence of cathodoluminescence and very low mn (gener-ally<50 ppm) contents of the samples, it is thought that they contain information on the orig-inal sea water geochemistry. The results of isotopic analyses of these samples are presented interms of δ^(13)C and ^(87)Sr/^(86)Sr ratios versus geological time. The strontium data, consistent withother similar data based on samples from North America, Europe, Africa and other areas inAsia, support the notion of a global consistency in strontium isotope composition of marinecarbonates. The strontium data exhibit three intervals of relatively low ^(87)Sr/^(86)Sr ratios in thelate Middle Devonian to early Late Devonian, Early Carboniferous and Early Permian, corre-sponding to global eustatic high sea level stands. The lowest ^(87)Sr/^(86)Sr ratio recorded in theLate Permian was probably caused by substantial basalt eruptions in the Upper Yangtze Plat-form at the time. Three corresponding periods of relatively high δ^(13)C values at roughly the samethe intervals were caused by a relatively high rate of accumulation of organic carbon duringsea level rises at these times. The deposition of coal was probably responsible for the increaseof sea water δ^(13)C at other times. The δ^(13)C values drop dramatically near theDevonian/Carboniferous, Carboniferous/Permian and Permian/Triassic boundaries, con-sistent with other similar data, which further support the notion that geological time boundariesare associated with mass extinction and subsequent rejuvenation.

关键词： Upper Yangtze Platform Late Palaeozoic marine carbonate carbon and strontium isotopes

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TRACE AND MINOR ELEMENT GEOCHEMISTRY OF XIANGDONG TUNGSTEN DEPOSITS

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Journal of Central South university 1996年第1期8卷 75-77页

作者： Chen Zilong Yang Chuxiong(Department of geology, Central South university ofTechnology, Changsha {2.0083, China)

Geochemical characteristics of trace and minor elements in some strata of geosynclinal tectonic layer, platform tectonic layer, in granite of Diwa stage, altered rocks and wolframite in the Xiangdong Tungsten Mine are systematically studied. Enrichment of W, Sn and Cu in geosynclinal tectonic layer could be one part of mineralization. Different types of alteration might result in variance of distribution of the same trace or minor element. mNb/mTa and mmn/mFe ratios, contents of Nb and Ta in wolframite vary with vein groups′ location.

关键词： trace element minor element granite tungsten deposits Hunan

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Gold Deposits in Precambrian Banded Iron-Formations——A Case Study of the Dongfengshan Gold Deposit

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Acta Geologica Sinica(English Edition) 1987年第1期 67-82+118页

作者： Liu Jinglan Institute of geology, Heilongjiang Bureau of geology and Mineral Resources, Harbin

This paper deals with a preliminary study of 13 localities of Precambrian iron-formations in the Jiamusi median massif and determination of the gold eontent of 391 samples. It has been ascertained that the gold deposits are strictly controlled by the iron-formations and exhibit obvious stratabound features. On that basis, the paper principally discusses gold migration and enrichment. Abundant mn and Co are contained in primary sediments of the Dongfengshan-type gold deposits, which strongly supports and supplements the idea that the gold deposits of the same kind in the world are of metamorphosed volcanoexhalative-sedimentary origin.

关键词： Gold Deposits in Precambrian Banded Iron-Formations A Case Study of the Dongfengshan Gold Deposit

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PROFESSOR YE LIANJUN’S 50 YEARS IN GEOSCIENCE

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沉积学报 1987年第3期 4-5页

作者： Institute of geology, Academia Sinica Academia Sinica Institute of geology

*** Lianjun has already in geoscience for 50 years since he graduatedfrom the Department of geology,Beijing university in *** a geologist,especially a sedimentologist,he is well known both in China and in the *** a member of Devision,the Academia Sinica,deputy director of the Division ofEarth Science the Academia Sinica,chairman of the Scientific Researh Committeeand Degree Committee of Institute of geology,Academia Sinica,deputy council

关键词： S 50 YEARS IN GEOSCIENCE PROFESSOR YE LIANJUN

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AN EXPRESSION OF LATTICE AND CALCULATION OF DIMENSION OF THE FRACTAL STRUCTURE FOR QUASICRYSTAL

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Chinese Science Bulletin 1989年第18期34卷 1548-1550页

作者：沈步明 Institute of geology Academia Sinica Beijng

D. Shechtman et al. reported a new long-range-ordered phase without translational symmetry in a quenched alloy of AI and 14. mn. This phase is called quasicrystal. Soon afterwards, these quasicrystals have been discov... 详细信息

关键词： quasicrystal structure fractal fractal dimension lattice

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