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Boron Isotopic Fractionation and Trace Element Incorporation in Various Species of Modern Corals in Sanya Bay, South China Sea

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Journal of Earth Science 2014年第3期25卷 431-444页

作者： Haizhen Wei shaoyong jiang Yingkai Xiao N Gary Hemming State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth ResourcesChina University of Geosciences Wuhan Qinghai Institute of Salt Lakes Chinese Academy of Sciences Lamont-Doherty Earth Observatory of Columbia University Queens College School of Earth and Environmental Sciences

The boron isotope paleo-pH proxy has been extensively studied due to its potential for understanding past climate change, and further calibrations were considered for accurate applications of the proxy because of significant variability related to biocarbonate microstructure. In this work, we studied the boron isotopic fractionation between modern marine corals and their coexisting seawater collected along shallow area in Sanya Bay, South China Sea. The apparent partition coefficient of boron（KD） ranged from 0.83×10-3 to 1.69×10-3, which are in good agreement with previous studies. As the analyzed coral skeleton（~5 g） spanned the growth time period of 1–2 years, we discussed the boron isotopic fractionation between pristine corals and modern seawater using the annual mean seawater pH of 8.12 in this sea area. Without taking the vital effect into account,（11B/10B）coral values of all living corals spread over the curves of（11B/10B）borate vs.（11B/10B）sw with the α4-3 values ranging from 0.974 to 0.982. After calibrating the biological effect on the calcifying fluid pH, the field-based calcification on calcifying fluid pH（i.e., Δ（pHbiol-pHsw）） for coral species of Acropora, Pavona, Pocillopora, Faviidae, and others including Proites are 0.42, 0.33, 0.36, 0.19, respectively, and it is necessary to be validated by coral culturing experiment in the future. Correlations in B/Ca vs. Sr/Ca and B/Ca vs. pHbiol approve temperature and calcifying fluid pH influence on skeletal B/Ca. Fundamental understanding of the thermodynamic basis of the boron isotopes in marine carbonates and seawater will strengthen the confidence in the use of paleo-pH proxy as a powerful tool to monitor atmospheric CO2 variations in the past.

关键词： boron isotope paleo-pH proxy boron isotopic fractionation trace element modern coral.

The age and tectonic environment of the rhyolitic rocks on the western side of Wuyi Mountain,South China

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Science China Earth Sciences 2008年第8期51卷 1053-1063页

作者： SHU LiangShu DENG Ping YU JinHai WANG YanBin jiang shaoyong State Key Laboratory for Mineral Deposits Research Department of Earth SciencesNanjing UniversityNanjing 210093China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Center of Iron-Probe in Beijing Beijing 100037China

During the geological survey of the metamorphic rocks in Xingning-Wuhua region on the western side of Wuyi Mountain, South China, we discovered the Neoproterozoic rhyolite and rhyolitic greywacke for the first time that outcrop in the Proterozoic metamorphic rocks near Jingnan Town of Xingning County, eastern Guangdong Province. A systematic research on petrology, geochemistry and geochronology of rhyolitic rocks was conducted to understand their tectonic setting and formation age. The Jingnan rhyolite is interbedded with a coeval greywacke, with a total thickness of 60 m; both rhyolite and greywacke display a similar folding and metamorphic pattern. Meta-rhyolite consists of groundmass and phenocrystals including sanidine, orthoclase, and quartz with distinct undulose extinction; the groundmass has been recrystallized into fine-grain feldspar, quartz and sericite aggregation. Meta-greywacke is composed of crystallinoclastic grains (sanidine, orthoclase, quartz and oligoclase) and clay groundmass. Zircon grains used for the SHRIMP U-Pb analysis are light brown-colored and euhedral or subeuhedral. Dating data suggest two age groups; eight grains of magmatype zircon with an idiomorphic form yield an age of 972±8 Ma, and the other seven weakly corroded grains of zircon with euhedral to subeuhedral shape construct an average age of 1097±11 Ma, which were captured from older rocks by an uplifting magma, implying that a late Mesoproterozoic basement exists in the Nanling region. In addition, one Paleoproterozoic age, 2035±11 Ma, is obtained from a rounded detrital zircon, indicating that a Paleoproterozoic thermal event took place in the South China. Geochemically, the Jingnan rhyolitic rocks are characterized by high K2O content, intermediate Al2O3 content, with the ACNK value 0.98―1.11, and belonging to high-K alkaline series. They are rich in ΣREE, Rb, Th and Ce, depleted in Ba, Sr, Eu, Ti, P and Nb-Ta, and with moderate negative Eu and Sr anomalies. These features ind

关键词： rhyolite calc-alkaline series early stage of Neoproterozoic western Wuyi Mountain South China

Geochronology and Hf Isotope Study of Pegmatite in the Xiaoqinling Area of NW China: Implication for Petrogenesis and Regional Metamorphism

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Journal of Earth Science 2015年第3期26卷 295-305页

作者： Haixiang Zhao shaoyong jiang Baozhang Dai Liang Ma Jianwei Li School of Earth Sciences and Engineering Hohai University State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth ResourcesChina University of GeosciencesWuhan State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing University

In this study, we carried out petrography, zircon U-Pb geochronology and Hf isotopic analyses on a granitic pegmatite dyke in the Xiaoqinling area in southern margin of the North China Craton（NCC）. Our study suggests that the pegmatite dyke likely crystallized from a volatile-rich pegmatitic magma. Different from most other pegmatite elsewhere, zircon from this pegmatite dyke does not contain unusually high U and Th concentrations and suffered no evident radioactive damage, therefore we successfully obtained a zircon U-Pb dating using laser ablation-inductively coupled plasma-mass spectrometry（LA-ICP-MS）, which yields an average 207Pb/206 Pb age of 1 814±6 Ma, representing the intrusive age of the granitic pegmatite dyke. Zircon εHf（t） values are between-8.3 and-3.0, corresponding to Hf depleted mantle model ages from 2 649 to 2 991 Ma with an average of 2 881 Ma. These data indicate that this granitic pegmatite dyke may have been derived from partial melting of Meso-Neoarchean metamorphic rocks from the Xiaoqinling basement. Granitic pegmatite magma may have emplaced within the Taihua Group wall rocks during the last stage of the middle to high grade metamorphism. Furthermore, according to the petrographic observation, the 1.81 Ga pegmatite dyke and the 1 800–1 750 Ma Xiong’er Group rocks were not undergone middle to high grade metamorphism, indicating 1.81 Ga as the termination of the latest regional metamorphism in the southern margin of the NCC.

关键词： Xiaoqinling pegmatite zircon U-Pb dating Hf isotope metamorphism

In situ Analysis of Major Elements, Trace Elements and Sr Isotopic Compositions of Apatite from the Granite in the Chengchao Skarn-Type Fe Deposit, Edong Ore District： Implications for Petrogenesis and Mineralization

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Journal of Earth Science 2018年第2期29卷 295-306页

作者： Zhenghan Li Dengfei Duan shaoyong jiang Ying Ma Hongwei Yuan School of Earth Sciences China University of Geosciences Wuhan 430074 China Collaborative Innovation Center for Exploration of Strategic Mineral Resources China University of Geosciences Wuhan 430074 China Faculty of Earth Resources China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China The First Geological Brigade of Hubei Geological Bureau Huangshi 435100 China

Major elements, trace elements and Sr isotopic compositions of apatite from the granite in the Chengchao skarn-type Fe deposit of Edong ore district of Middle-Lower Yangtze River metallogenic belt were measured using EMPA （electron microprobe）, LA-ICP-MS （laser ablation inductively coupled plasma mass spectrometer） and LA-MC （multicollector）-ICP-MS methods in order to reveal the petroge- netic and metallogenic significance of the skarn-type iron deposits. The results show that the apatite in Chengchao granite is fluorapatite, which displays slight variation in major elements. The REE distribution pattern of the apatite is similar to that of the whole rocks, with strong negative Eu anomaly and low Sr/Y ratio. The concentration of Mn in apatite is low （140 ppm-591 ppm） and the Sr isotopic composition shows a limited variation from 0.706 9 to 0.708 2. The high oxygen fugacity of the Chengchao granite, implied by the low Mn content in apatite, is possibly attributed to contamination of the gypsum from sedimentary rock strata, which has long been thought to be an important factor that controls the Fe mineralization in the Middle-Lower Yangtze River metallogenic bell This study also proves that the Eu/Eu＊ value and Sr/Y ra- tio in apatite can be effectively used to identify the adakitie affinity. The in situ Sr isotope analysis of apatite is in consistent with the bulk rock analysis, which indicates that the apatite Sr isotope can represent the ini- tial Sr isotopic compositions of the magma. The Sr isotope and negative Eu anomaly in apatite imply that the Chengchao granite is likely sourced from crust-mantle mixed materials.

关键词： apatite in situ analysis Sr isotopes trace elements adakite identification oxygen fugacity.

Rare Earth Element Geochemistry of Phosphatic Rocks in Neoproterozoic Ediacaran Doushantuo Formation in Hushan Section from the Yangtze Gorges Area, South China

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Journal of Earth Science 2016年第2期27卷 204-210页

作者： Hong Xin shaoyong jiang Jinghong Yang Heping Wu Daohui Pi State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University State Key Laboratory of Geological Processes and Mineral Resources Collaborative Innovation Center for Exploration of Strategic Mineral Resources Faculty of Earth Resources China University of Geosciences

Phosphatic rocks are widely distributed in Neoproterozoic Ediacaran Doushantuo Formation in Yangtze Gorges Area, South China. In this study, rare earth element geochemistry of eight phosphatic rock samples from the Hushan Section has been studied. All the samples display typical hat-shaped REE patterns, moderate negative Ce anomalies（Ce/Ce＊=0.55 to 0.67）, slightly positive Eu anomalies（Eu/Eu＊=1.05 to 1.22） and low Y/Ho ratios（38.2±5.6）. The hat-shaped REE patterns indicate diagenetic alteration of the primary REE signatures, which coincides with detrital siliciclastic sources of REE based on the Y/Ho ratios. The degree of Negative Ce anomalies and positive Eu anomalies may have recorded the redox features of diagenetic fluids, suggesting an anoxic environment during the phosphogenesis processes in Neoproterozoic Ediacaran Doushantuo Formation, South China. The geochemical comparison between the Lower Phosphorite Layer and Upper Phosphorite Layer at Hushan indicates a greater degree of diagenesis occurred in the Upper Layer than the Lower one. Besides the terrigenous sources of REE, organic materials could have also played a role on the REE characteristics.

关键词： phosphatic rocks rare earth element Ediacaran Doushantuo Formation YangtzeGorges area.

Trace Elements Characteristics of Black Shales from the Ediacaran Doushantuo Formation, Hubei Province, South China： Implications for Redox and Open vs. Restricted Basin Conditions

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Journal of Earth Science 2018年第2期29卷 342-352页

作者： Bi Zhu shaoyong jiang Daohui Pi Lu Ge Jinghong Yang Institute of Isotope Hydrology School of Earth Sciences and Engineering Hohai University Nanjing 210098 China State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Resources Collaborative Innovation Center for Exploration of Strategic Mineral Resources China University of Geosciences Wuhan 430074 China State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University Nanjing 210093 China

In the present study, we carried out trace element analyses of black shales of the Edia- caran Doushantou Formation from two sections （Jiulongwan, Baiguoyuan） in Hubei Province, South China. Mo-U characteristics of black shales from the two sections and compiled Mo-U data of Dou- shantuo black shales from sections of a variety of sedimentary facies described the temporal/spatial variability in the redox conditions of paleo-seawater during deposition of the Donshantuo Formation. Changes in Mo-U patterns of the Doushantuo Member II （DST2） shales of open marine environments are consistent with a shift from a predominately oxic to a predominately anoxic ocean during their deposition. Mo-U patterns of the DST2 black shales from intra-shelf sections reflect basin restriction may have happened in the intra-shelf basin and are compatible with the redox-stratified model of the intra-shelf basin. Mo-U patterns of black shales of the Doushantuo Member IV （DST4） reveal that the shales from intra-shelf sections have more pronounced Mo enrichment and more significant enrich- ment of Mo over U than the slope shales, indicating the operation of a Mn particulate shuttle in the intra-shelf basin. High Mo/TOC ratios of the DST4 at the intra-shelf sections, in combination with similar Mo-TOC patterns of the DST4 from both intra-shelf and slope sections, indicate the intra- shelf basin was well connected to the open ocean during deposition of the DST4.

关键词： Doushantuo Formation Mo-U eovariation Mo/TOC South China.

Origin of ore-forming fluids of the Dachang Sn-polymetallic ore deposit: Evidence from helium isotopes

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Chinese Science Bulletin 2002年第12期47卷 1041-1045页

作者： Kuidong Zhao shaoyong jiang Hongquan Xiao Pei Ni Nanjing Univ Dept Earth Sci State Key Lab Mineral Deposits Res Nanjing 210093 Peoples R China

The ore genesis model for the Dachang Sn-polymetallic ore deposit has long been in dispute, and the major debate focuses on whether the stratiform and massive orebodies formed during the Yanshanian magmatic-hydro-thermal event or they were products of Devonian syn-sedi-mentary exhalative-hydrothermal event. This note presents new helium isotope data from fluid inclusions of four pyrites and one fluorite. The pyrites were collected from the stratiform and massive orebodies in the deposit, and their 3He/4He ratios are significantly higher than 1, ranging from 1.7 to 2.5 Ra, which indicates a mantle component in the responsible hydrothermal fluids. It is suggested that the ore-forming fluids were a mixture of deep circulating seawater and a mantle-derived fluid, which are similar to many of those modern submarine hydrothermal fluids. In contrast, the fluorite, collected from a granite-related hydrothermal vein in the deposit, shows a low 3He/4He ratio of 0.7 Ra, which indicates no mantle component

关键词： He and Ar isotopes crustal fluid mantle fluid massive sulfide deposit Dachang Sn-polymetallic deposit.

SHRIMP U-Pb zircon dating for lamprophyre from Liaodong Peninsula: Constraints on the initial time of Mesozoic lithosphere thinning beneath eastern China

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Chinese Science Bulletin 2005年第22期50卷 2612-2620页

作者： jiang Yaohui jiang shaoyong ZHAO Kuidong NI Pei LING Hongfei LIU Dunyi State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China Beijing SHRIMP Center Beijing 100037 China

It is undebated fact that the lithospheric mantle beneath eastern China was considerably thinned during the Mesozoic time. However, it has no adequate evidence for the exact timing when the lithosphere thinning started. The Liaodong Peninsula is located in the eastern segment of the North China Craton and is one of the important domains to explore the event of lithosphere thinning. SHRIMP U-Pb zircon dating and geochemical study were carried out for the lamprophyre dike swarm that intruded into the magnesite ore-beds in the Dashiqiao Formation of Paleoproterozoic Liaohe Group at the Huaziyu magnesite ore district, Liaodong Peninsula. The results indicate that these lampro- phyre dikes were intruded in late Jurassic (155±4 Ma) and show some geochemical characteristics of potassic magmas. It is now accepted that the lithosphere thinning took place in the late Mesozoic, and the peak thinning stage occurred in early Cretaceous (130―120 Ma). Considering the potassic mafic magmatism marking the onset of the lithospheric thin- ning, we therefore suggest that the studied late Jurassic potassic lamprophyre dike swarm could imply that the late Jurassic is the time that lithosphere thinning started.

关键词：锆石煌斑岩中生代时期岩石圈辽东半岛

Jurassic sedimentary features and tectonic settings of southeastern China

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Science China Earth Sciences 2009年第12期52卷 1969-1978页

作者： SHU LiangShu WANG Yan SHA JinGeng jiang shaoyong YU JinHai WANG YanBin State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing 210093China LPS Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Liaohe Oilfield Company PetroChinaPanjin 124010China Beijing SHRIMP Center Chinese Academy of Geological SciencesBeijing 100037China

Two types of the Jurassic basins are distinguished in SE China based on their geodynamic features: the Late Triassic-Early Jurassic post-orogenic basins and the Middle Jurassic intra-continental extensional basins. The Lower Jurassic sequence shows a change from coarseto fine-grained accumulation, suggesting a gradually deepening depositional environment from river to shore-lake and to deep-water lake. In contrast, the Middle Jurassic accumulation was changed from claystone to conglomerate along the coastal provinces in SE China, indicative of an initial crustal uplift. The Wuyi Mountains have been a paleogeograghic separating zone since the Middle Jurassic. The Late Jurassic strata are absent in most areas of SE China. A large-scale bimodal intra-continental rift-type volcanism occurred during the Middle Jurassic along a 40-60 km wide and 200 km long area in western Fujian and southern jiangxi provinces, which is most likely the strongest volcanism in SE China since the Cambrian. The SHRIMP zircon U-Pb analyses on the rhyolite from the Dongkeng basin in the southern jiangxi area yield a concord U-Pb age of 160±0.5 Ma, providing an upper age limit for the bimodal volcanic eruption. The analyses of the basin features indicate a change of the depositional environment during the interval from Middle Triassic to Late Triassic from a shallow-sea to an intra-continent in SE China in response to the strong collision between the Yangtze and North China Blocks. Sedimentary structures record a southward direction of Early Jurassic paleo-currents, reflecting that their source areas were to the north side. We propose that the Wuyi region was uplifted as early as Middle Jurassic, followed by a wide E-W-trending extended depression and bimodal volcanism in the western foot of the Wuyi Mountains. Presumably the uplift of the Wuyi domain changed the Middle Jurassic paleo geographic outline and formed the transformational tectonic regime from compression to extension as a tectonic r

关键词： sedimentary features paleo-geographic framework tectonic transformation SHRIMP U-Pb dating Jurassic southeastern