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Trace element geochemistry of the Lower Cambrian black rock series from northwestern Hunan, South china

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Progress in Natural Science:Materials International 2004年第1期14卷 65-71页

作者： PAN Jiayong 1,2. *, MA Dongsheng 1 and CAO Shuanglin 1,2. (1.The state key {2. for mineral deposits research, nanjing university, nanjing 2.0093, china 2. East china Institute of Technology, Fuzhou 344000, china) The state key {2. for mineral deposits research Nanjing University Nanjing 210093 China. East china Institute of Technology Fuzhou 344000 China

Samples of black rock series collected from the Lower Cambrian Niutitang Formation, northwestern Hunan Province, china, were analyzed for trace elements. The trace element geochemical characteristics of the ore layer (high enrichments of Ni, Mo, V, U, Cu, Pb, Zn, Cd, Tl and Ba; high U/Th ratios and LREE enriched patterns with positive Eu and Y anomalies) support the assumption that the Ni Mo polymetallic layer is of submarine hydrothermal origin. High field strength elements (HFSE) and lithophile elements such as Nb, Ta, Zr, Hf, Li, Be, Rb, Cs, Th and Sc are remarkably higher in the upper unit than those in the lower unit of the Niutitang Formation. These features may reflect that hydrothermal contributions were diminished, and terrigenous constituents were increased in the sediments of the upper unit of the Niutitang Formation.

关键词： black rock series Early Cambrian trace elements northwestern Hunan china

Study on lithogeochemistry of Middle Jurassic basalts from southern china represented by the Fankeng basalts from Yongding of Fujian Province

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Science china Earth Sciences 2006年第10期49卷 1020-1031页

作者： ZHOU Jincheng1,2. JIANG Shaoyong1,2. WANG Xiaolei1,2. YANG Jinghong 1,2.& ZHANG Mengqun 3 1. state key {2. of mineral Deposit research, nanjing university, nanjing 2.0093, china 2. Department of Earth Sciences, nanjing university, nanjing 2.0093, china 3. Modern Analysis Center, nanjing university, nanjing 2.0093, china state key {2. of mineral Deposit research Nanjing University Nanjing China Department of Earth Sciences Nanjing University Nanjing China Modern Analysis Center Nanjing University Nanjing China

There exists an E-W trending Middle Jurassic volcanic zone in southern china. The Fankeng basalts in the Yongding basin of Fujian Province are considered to be a typical example. The Fankeng basalts have TiO2.contents in the range of 1.92.-3.2.%. They are classified as high-Ti basalts. They also have higher total Fe (averaging FeO* = 11.09%). The Middle Jurassic Fankeng basalts from southwestern Fujian have obvious distinctive lithogeochemical features from early Cre- taceous basalts from southeastern coast of china. They have higher HFSE, such as Th, Nb, Ta, Zr and Ti. Their element ratios related with HFSE, such as Zr/Ba, La/Nb, La/Ta ,Zr/Y, Ti/Y, Ba/Nb, K/Ti and Rb/Zr are similar to those of OIB. The most samples have ε Nd(T) of-0.70-0.2., which are near chondrite. Some samples have higher ε Nd(T) of ***, these basaltic magmas might be derived from depleted asthenospheric mantle. The lithogeochemical characteristics of the Fankeng basalts may be caused by interaction between asthenosphere and lithosphere at the time. The (Early-) Middle Jurassic basalts and gabbros from southeastern Hunan, southern Jiangxi and northern Guangdong provinces show similar geochemical features to those of the Fankeng basalts from the Yongding of Fujian. Occurrence of these OIB-type basalts in the area may be regarded as the petrological mark of upwelling of asthenosphere at the time. Upwelling of asthenosphere has led to tectonic extension and the formation of rifted basin in the area.

关键词： interaction between asthenosphere and lithosphere, lithogeochemistry, basalts, Middle Jurassic, southern china.

Water in peridotite xenoliths from South china

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Science china Earth Sciences 2011年第10期54卷 1511-1522页

作者： WANG Rong 1,2.3 & ZHANG BaoMin 3 1 Faculty of Land Resource Engineering, Kunming university of Science and Technology, Kunming 650093, china 2.{2. key laboratory for mineral deposits research, nanjing university, nanjing 2.0093, china 3 Faculty of Earth Science, china university of Geosciences, Wuhan 430074, china Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming China state key {2. for mineral deposits research Nanjing University Nanjing China Faculty of Earth Science China University of Geosciences Wuhan China

The water contents of nominally anhydrous clinopyroxene （cpx）, orthopyroxene （opx） and olivine （ol） in peridotite xenoliths hosted by Cenozoic basalts from Yingfengling, Zhangchouchun, Fujitian and Lindi, South china, were measured by Micro- FTIR. All cpx and opx grains contained a certain amount of water, which was indicated by the presence of hydroxyls in the crystal structure. The water contents （H2., ppm） of cpx and opx from peridotite xenoliths of the study areas were 2.3-981, 183-752. 73-586 and 51-42. ppm, and 82.471, 74-571, 53-170 and 9-135 ppm, respectively. No prominent OH absorption bands were detected for any ol grains, indicating that the water contents were below the detection limit （approximately 2.ppm）. The entire rock contents recalculated according to mineral volume proportions were 49-163, 48-168, 2.-111 and 8-40 ppm, respectively. Combined with previously reported data describing the water contents of peridotite xenoliths worldwide, the results presented here suggest that water distribution in the continental lithospheric mantle is spatially heterogeneous at a global scale. The lithospheric mantle of South china is much richer in water than that of the North china Craton, and is close to that typical of off-craton localities, such as the Basin and Range Province, and Massif Central.

关键词： FTIR water peridotite xenoliths South china

The relationship between epithermal and low temperature mineralizations

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Chinese Science Bulletin 1999年第S2期44卷 226-227页

作者： HUA Renmin state key {2. of mineral Deposit research, nanjing university, nanjing 2.0093, china state key {2. of mineral Deposit research Nanjing University Nanjing 210093 China

THE term epithermal as a kind of hydrothermal mineralization was first used by Lindgren in 1933. It describes those ore-forming systems occurring at depths mainly less than 1 km, and at temperatures less than300℃. Epithermal deposits of Cenozoic ages are widely distributed in the Circum-Pacific belt, especiallyin the Southwest Pacific area. From the 1980s on, the study of epithermal ore deposits became an important field of mineral deposit research. Hayba et *** Hedenquist classified the epithermal systemas adularia-sericite or acid-sulphate types, and low sulphidation or high sulphidation types, *** low temperature mineralization, which was exemplified by the deposits in southwest china, refers tothe system at temperature mainly less than 2.0℃. Besides the distinction in temperature, however, thereexist many differences between epithermal and low temperature mineralizations.

关键词： epithermal mineralization low temperature.

Carbon and sulfur isotopic compositions of basal Datangpo Formation, northeastern Guizhou, South china:Implications for depositional environment

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Progress in Natural Science:Materials International 2008年第4期18卷 421-429页

作者： Xi Chen, Da Li, Hong-Fei Ling , Shao-Yong Jiang state key {2. for mineral Deposit research, Department of Earth Sciences, nanjing university, nanjing 2.0093, china state key {2. for mineral Deposit research Department of Earth Sciences Nanjing University Nanjing 210093 China

Isotopic compositions of Mn-carbonate and organic carbon from the same individual samples and sulfur isotopic compositions of pyrites in the basal Datangpo Formation were analyzed. Highly 34S-enriched pyrites (d34Spyrite=31.7-59.4‰) were precipitated in rel- atively occlusive pore water under anoxic condition in sediments, which is consistent with the observation of large and scattered pyrite framboids. The sulfidic deep ocean was not "oxidized" in the early Datangpo interglacial interval, thus the level of seawater sulfate remained low and marine d34Ssulphate remained high. Low d13Ccar (average 7.4‰) and abnormal relationship between d13Ccar and frac-tionation (Dcar-org) imply that the negative d13Ccar excursion may have resulted from oxidation of part of a large organic carbon reser-voir. High Dcar-org (average 2..1‰) implicates high CO2.level in the atmosphere. Small standard deviation (1.0‰) of d13Ccar values indicates the Mn-carbonate was precipitated near the water-sediment interface under dysoxic conditions rather than in occlusive pore water in sediments.

关键词： Cisotope S isotope Paleoenvironment Datangpo Mn-carbonate

Advances in research of sulphide ore textures and their implications for ore genesis

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Progress in Natural Science:Materials International 2006年第10期16卷 1007-1021页

作者： GU Lianxing, ZHENG Yuanchuan, TANG Xiaoqian, WU Changzhi and HU Wenxuan (state key {2. for Endogenic Metal deposits research, Department of Earth Sciences, nanjing university, nanjing 2.0093, china) state key {2. for Endogenic Metal deposits research Department of Earth Sciences Nanjing University Nanjing 210093 China

Important advances in research of sulphide ore textures in recent years have deepened our understanding of ore genesis of related mineral {2.. Pressure solution of sulphide minerals has been suggested as a mechanism for remobilization of ore materials, whereas pressure solution of the gangues is believed to raise the grade of the primary ores. We have known that precipitation of base metal sulphides from fluids prefers crystal and crack surfaces of pyrite to form overgrowth. Therefore, pyrite-bearing embryo beds in a sedimentary sequence can be acted as effective crystal seed beds and are favorable for fluid overprinting to form huge statabound {2.. Texture studies of various sulphides can be used to interpret the entire history of sedimentation, diagenesis, deformation and metamorphism of the ores. The study of chalcopyrite disease in sphalerite has brought about the idea of zone refining, and given a new explanation to metal zonation in massive sulphide {2.. Ductile shearing of sulphide ores may form ore mylonites, which will become oreshoots enriched in Cu, Au and Ag during late-stage fluid overprinting. Despite that various modern analytical techniques are being rapidly developed, ore microscopy remains to be an unreplaceable tool for ore geologists. Combined with these modern techniques, this tool will help accelerate the development of theories on ore genesis.

关键词： pyrite pyrrhotite chalcopyrite pressure sulution overgrowth mylonite.

Evolution of chlorite composition in the Paleogene prototype basin of Jiyang Depression, Shandong, china, and its implication for paleogeothermal gradient

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Science china Earth Sciences 2007年第11期50卷 1645-1654页

作者： ZHAO Ming1, CHEN XiaoMing1, JI JunFeng1, ZHANG Zhe1 & ZHANG Yun2.1 state key {2. for mineral deposits research, Department of Earth Sciences, nanjing university, nanjing 2.0093, china 2.Jiangsu Survey Institute of Engineering and Physics, nanjing 2.0008, china state key {2. for mineral deposits research Department of Earth Sciences Nanjing University Nanjing China Jiangsu Survey Institute of Engineering and Physics Nanjing China

The Dongying Basin, Huimin Basin, and Zhanhua Basin constitute the Jiyang Depression in Shandong Province. They are major oil and gas exploring districts within the depression. Through reconstructions of the paleotemperature of the three basins facilitated with the chlorite geothermometry, the thermal history of the Paleogene prototype basin in Jiyang Depression and its geologic significance were explored. This study reveals that the Si^(4+) component in chlorites reduces gradually as its buried depth increases, while the AI~Ⅳ component increases accordingly. The chlorite type changes from silicon-rich diabantite to silicon-poor ferroamesite and prochlorite. The prochlorite in this district only appears in the deep buried depth, high temperature, and relatively old stratigraphies; while the diabantite appears in the shallower buried, low temperature, and newly formed strata; the ferroamesite exists in the conditions between prochlorite and diabantite formation. The diagenetic temperatures of the chlorites in these Paleogene basins are 171 — 2.8℃ for the Dongying Basin, 160—2.2. for the Huimin Basin, and 135—180℃ for the Zhanhua Basin. The differences of the chlorite diagenetic temperatures in the three basins were controlled by the duration time of the structural depressing processes. Higher temperature indicates longer depression time. The relationship between the chlorite diagenetic temperature and its buried depth indicates that the average paleogeothermal gradient is about 38.3℃ /km in the Paleogene prototype basin of Jiyang Depression. It was higher than the present geothermal gradient (2.—30℃/km). This phenomenon was attributed to the evolution of the structural dynamics in the depression basin.

关键词： Paleogene,Jiyang depression,chlorite component,chlorite geothermometry,paleotemperature,paleogeothermal gradient

Geothermal and fluid flowing simulation of ore-forming antimony deposits in Xikuangshan

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Science china Earth Sciences 2006年第8期49卷 862-871页

作者： YANG Ruiyan1,2. MA Dongsheng2. BAO Zhengyu3, PAN Jiayong2. CAO Shuanglin2.& XIA Fei2.1. School of Mathematics and Physics, china university of Geosciences, Wuhan 430074, china 2. state key laboratory for research of mineral deposits, nanjing university, nanjing 2.0093, china 3. Faculty of Earth Sciences, china university of Geosciences, Wuhan 430074, china School of Mathematics and Physics China University of Geosciences Wuhan China state key {2. for research of mineral deposits Nanjing University Nanjing 210093 China Faculty of Earth Sciences China University of Geosciences Wuhan China

The Xikuangshan Antimony Deposit located in the Mid-Hunan Basin, china, is the larg- est antimony deposit in the world. Based on the hydrogeological and geochemical data collected from four sections, Xikuangshan-Dajienao (AO), Xikuangshan-Dashengshan (BO), Xikuang- shan-Longshan (CO) and Dafengshan (DO) in the Basin, an advanced metallogenic model related to deep-cyclic meteoric water of Xikuangshan Antimony Deposit is put forward in this paper using a model of heat-gravity-driving fluid flow transportation. The simulation results show that the ore-forming fluid of the deposit mainly comes from the Dashengshan and Longshan areas where BO and CO sections are located if the overall basin keeps a constant atmospheric precipitation and infiltration rate during mineralization, and that the average transportation speed of the ore-forming fluids is about 0.2.0.4 m/a.

关键词： ore-forming fluid, numerical simulation, geothermal field, geofluid transport, Xikuangshan, antimony deposits.

Sensitive biosensing strategy based on functional nanomaterials

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Science china Chemistry 2011年第8期54卷 1202-1217页

作者： JU HuangXian state key {2. of Analytical Chemistry for Life Science Department of Chemistry, nanjing university, nanjing 2.0093, china state key {2. of Analytical Chemistry for Life Science Department of Chemistry Nanjing University Nanjing China

The first decade of the 2.st century has been labeled as "the sensing decade". The functional nanomaterials offer excellent platforms for fabrication of sensitive biosensing devices, including optical and electronic biosensors. A lot of works have fo- cused on the biofunctionalization of different nanomaterials, such as metal nanoparticles, semiconductor nanoparticles and carbon nanostructures, by physical adsorption, electrostatic binding, specific recognition or covalent coupling. These biofunc- tionalized nanomaterials can be used as catalysts, electronic conductors, optical emitters, carriers or tracers to obtain the ampli- fied detection signal and the stabilized recognition probes or biosensing interface. The designed signal amplification strategies have greatly promoted the development of stable, specific, selective and sensitive biosensors in different fields. This review in- troduces some novel principles and detection strategies in the area of biosensing, based on functional nanomaterials. The gen- eral methods for biofunctionalization of nanomaterials with biomolecules and their biosensing application in immunoassay of protein, DNA detection, carbohydrate analysis and cytosensing are also described.

关键词： nanobiosensing biosensors nanomaterials biofunctionalization signal amplification bioanalysis biological recognition