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Metal records in lake/reservoir sediments adjacent to different pollution sources from Guizhou, southwestern China

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Acta Geochimica 2006年第S1期 13-13页

作者： Xiangyang BI1,2. Xinbin FENG1, Yuangen YANG1, Guangle qiu1, Xiaoli QIAN3. Weiyang BAI1,2. Zhongqing WEI1,2. Taoze LIU1,2.1 State Key Laboratory of Environmental geochemistry, {2. of geochemistry, Chinese {3. of sciences, Guiyang 550002. China 2.Graduate School of the Chinese {3. of sciences, Beijing 10003., China 3.School of Resources and Environmental Engineering, Guizhou University, Guiyang 550003. China

Geochemical evidence for submarine hydrothermal origin of the Middle-Upper Permian chert in Laibin of Guangxi, China

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Science China Earth sciences 2011年第7期54卷 1011-1023页

作者： qiu Zhen WANG QingChen State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese academy of sciences Beijing 100049 China

Lithologically, two kinds of chert can be recognized in the Middle-Upper Permian from the Tieqiao section in Laibin area, Guangxi, i.e., calcic chert occurring mainly in the Maokou Formation and pure chert mainly in the Wujiaping Formation. Geochemical data show that both kinds of chert contain very low A12.3.（0-0.2.%） and TiO2.（0.001%-0.02.%） and low ZREE （0.55-19.94 ppm, averaging 9.97 ppm）, as well as high ratio of Fe2.3.TiO2.（17-443. averaging 111） and low ratio of A12.3.（Al2.3.Fe2.3. （0-0.2., averaging 0.09）. Given that the average value Ce anomalies in chert deposited in the ridge-proximal environment is about 0.2., and that in the pelagic environment is about 0.60, the low Ce anomalies in the Tieqiao chert （0.2.-0.46, averaging 0.3.） imply that they were deposited in an ocean basin with influence of submarine hydrothermal fluid and no input of terrigenous materials. The vertical variation of the silica abundance in strata （SAIS） in the Middle-Upper Permian strata, together with the Eu anomalies and the ratios of ∑REE/Fe, indicates a relationship between the hydrothermal activity and the Emeishan basalt eruption, and that submarine hydrothermal activity was stronger in the Upper Permian （the Wujiapingian Stage） than in the Middle Permian （the Maokou Stage）.

关键词： chert geochemistry submarine hydrothermal fluid Emeishan basalt

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闽西晚中生代基性脉岩稀土元素地球化学特征

中国稀土学报 2008年第4期26卷 503-509页

作者：张贵山温汉捷胡瑞忠裘愉卓长安大学地球科学与国土资源学院陕西西安710054 中国科学院地球化学研究所矿床地球化学国家重点实验室贵州贵阳550002

利用稀土元素特征对闽西基性脉岩的成岩方式和岩浆演化机制进行探讨。闽西基性岩脉的稀土元素参数与常量元素的协变关系表明岩浆在上升侵入过程中可能没有发生地壳混染作用,在成岩过程中结晶分异作用可能不明显;多种稀土元素协变关系表... 详细信息

利用稀土元素特征对闽西基性脉岩的成岩方式和岩浆演化机制进行探讨。闽西基性岩脉的稀土元素参数与常量元素的协变关系表明岩浆在上升侵入过程中可能没有发生地壳混染作用,在成岩过程中结晶分异作用可能不明显;多种稀土元素协变关系表明闽西基性脉岩的成岩机制可能为上地幔部分熔融作用,基性脉岩的地幔源区可能曾经遭受过俯冲流体交代富集作用,这种交代可能与古太平洋板块俯冲密切相关,软流圈地幔上涌导致地壳拉张作用的发育。

关键词：基性脉岩成岩方式闽西稀土

Weathering of phosphorus-bearing mineral powder and calcium phosphate by Aspergillus niger

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Chinese Journal Of geochemistry 2012年第4期31卷 390-397页

作者： qiu Shuangshuang LIAN Bin State Key Laboratory of Environmental geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002China Graduate University of Chinese academy of sciences Beijing 100049China

The weathering of phosphorus-bearing mineral powder(PBMP) and calcium phosphate(CP) by Aspergillus niger was compared,and the mechanism involved was analyzed for the comprehensive utilization of *** concentration of water-soluble phosphorus(WSP),Mg2.,and Ca2.at different culture times,microstructures of particles,and mineral compositions was examined by ultraviolet-visible spectrometer(UV),atomic absorption spectrometry(AAS),scanning electron microscopy(SEM),and X-ray diffraction(XRD).Results showed that the change in the concentrations of WSP,Mg2.,and Ca2.were related to the growth of *** and the different mineral *** with CP,PBMP was weathered harder by *** of the weathered mineral were found through *** not only showed traces of erosion damage but also appeared as a rhombohedron-like *** XRD test indicated that the weathering minerals can form water calcium *** analysis revealed that the mechanism of PBMP and CP weathering by *** was the collaborative result of mycelium biomechanical effects and the acid-soluble role of acidic *** phosphorus dissolution rate of PBMP after 2. d was 46.83.,whereas that of CP after 12.d was 91.01%.The findings of this study are significant to the effective use of waste PBMP and to the exploitation of low-grade phosphate rock resources.

关键词：磷酸钙磷矿物黑曲霉紫外可见分光光度计原子吸收光谱仪 XRD测试老化 X-射线衍射

Controlling Factors on Organic Matter Accumulation of Marine Shale across the Ordovician–Silurian Transition in South China: Constraints from Trace-Element geochemistry

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Journal of Earth Science 2021年第4期32卷 887-900页

作者： Zhen qiu Huifei Tao Bin Lu Zhenhong Chen Songtao Wu Hanlin Liu Junli qiu Research institute of Petroleum Exploration and Development CNPCBeijing 100083China National Energy Shale Gas Research and Development(Experiment)Center Langfang 065007China Oil and Gas Research Center Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Oil and Gas Reservoirs CNPCBeijing 100083China National Energy Tight Oil and Gas R&D Center Beijing 100083China institute of Oil and Gas Peking UniversityBeijing 100871China

In recent years,significant progress in shale gas exploration has been achieved in the Upper Ordovician(Wufeng Formation)–Lower Silurian(Longmaxi Formation)shales in the Upper Yangtze area,South *** many studies have been carried out on the Upper Ordovician–Lower Silurian shales,the controlling factors causing organic matter accumulation of these shales remain *** study uses trace-element geochemistry and sedimentological methods to evaluate terrigenous input,redox conditions and primary productivity to explore the mechanisms of organic matter *** variation of terrigenous fraction elements(Al,Th and Sc)concentrations reflect a mixed influence of sea-level change and *** sea-level of the Upper Yangtze Sea went through two cycles of transgression to regression during the Ordovician–Silurian *** Linxiang Formation,Kuanyinchiao Bed and the upper part of Longmaxi Formation developed during the periods of regression,whereas the Wufeng Formation and the lower part of the Longmaxi Formation developed during the periods of *** paleo-productivity indexes of TOC content,ratios of Ba/Al and P/Al,and redox conditions proxies of Mo concentration,ratios of U/Th and V/Cr generally display similar variation patterns with respect to the sea-level *** TOC contents and Ba/Al and P/Al ratios indicate the paleo-productivity was high on the sea surface,as shown by relatively good positive correlations between Th ***,and Sc *** indicates that the paleo-productivity was controlled by the nutrients input through *** good positive correlations between redox conditions indexes(U/Th and V/Cr ratios)with TOC content reflects reductive preservation conditions(anoxic to euxinic),thus implying they were an important controlling factor for organic matter ***,redox conditions were closely associated with sea level change and organic matter ***,the sea-lev

关键词： productivity redox sea-level change shale gas Sichuan Basin Wufeng-Longmaxi shale

川北—鄂西上二叠统富有机岩沉积与地球化学特征

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沉积学报 2024年第3期42卷 774-798,I0001页

作者：韦恒叶胡谍邱振张璇刘雯孔维亮 Mansour Ahmed 西南石油大学地球科学与技术学院成都610500 西南石油大学羌塘盆地研究院成都610500 中国石油天然气股份有限公司勘探开发研究院北京100083

【目的】随着非常规油气理论的发展,沉积有机质富集机理再次成为热点研究,其中有机质富集主控因素成为争论的焦点。以往的研究对沉积过程的分析较少,这可能是存在争论的原因之一。【方法】结合沉积学与地球化学研究方法,在分析层序地层... 详细信息

【目的】随着非常规油气理论的发展,沉积有机质富集机理再次成为热点研究,其中有机质富集主控因素成为争论的焦点。以往的研究对沉积过程的分析较少,这可能是存在争论的原因之一。【方法】结合沉积学与地球化学研究方法,在分析层序地层学和沉积环境的基础上,详细开展元素地球化学研究,讨论富有机岩沉积有机质富集机理。【结果】四川盆地北部和鄂西盆地上二叠统吴家坪组自下而上分为吴一段、吴二段和吴三段,大隆组自下而上分为大一段和大二段。吴家坪组至大隆组自下而上总共分为五个三级层序SQ1~SQ5。由层序地层学分析将广利海槽和鄂西海槽的发展分为四个阶段,分别为初始、快速发展、高潮稳定和萎缩阶段。初始阶段主要发育SQ2.期斜坡相暗色硅质灰岩,快速发展阶段主要发育SQ3.期陆棚相钙质页岩,高潮稳定阶段主要发育SQ4时期盆地相黑色硅质岩,萎缩阶段主要发育SQ5时期斜坡相石灰岩。含异常高有机质的甜点段主要形成于SQ3.位域至SQ5海侵域沉积期,在该时期Fe、Cu、Ni和Zn营养元素周期性富集,Mo、V、Fe/Al和S等氧化还原敏感元素均表现为较高的水平,热液强度参数Al/(Al+Fe+Mn)和Al-Fe-Mn三角图均指示频繁的热液活动特征。【结论】在甜点段,高营养元素含量和初级生产力水平的出现早于强还原条件,说明沉积水体的氧化还原条件主要受控于沉积有机质沉降埋藏过程中对氧的消耗,有机质的富集主要受较高初级生产力的控制。营养物质P、Si、Fe、Zn的供应主要与裂陷槽形成过程中深部热液活动和周围火山活动有关,这些构造活动周期性带来大量营养物质提高了初级生产力水平。因此海洋表层高的初级生产力水平是甜点段异常高有机质富集的启动和基础条件,而海洋底部水体较强的还原环境是有机质埋藏和保存的关键因素。

关键词：富有机岩甜点段吴家坪组大隆组层序地层元素地球化学四川盆地鄂西盆地

geochemistry of the Middle to Late Permian limestones from the marginal zone of an isolated platform(Laibin,South China)

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Science China Earth sciences 2013年第10期56卷 1688-1700页

作者： qiu Zhen WANG QingChen YAN DeTian State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences PetroChina Research institute of Petroleum Exploration and Development Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education University of Geosciences

Major, trace and rare earth elements were measured in 2. samples of the Middle to Late Permian limestones from the Tieqiao section located on the marginal zone of an isolated platform （Laibin, South China）. Shale-normalized REE＋Y patterns of all samples show notably negative Ce anomalies （0.2.-0.66, average 0.3.）, slightly positive Gd anomalies （1.08-1.3., average 1.2.）, and positive Y anomalies with superchondritic Y/Ho ratios （3.-91, average 55）, which are consistent with those of modern shallow seawater. Their relative LREEs enrichment with higher NdsN/YbsN ratios （0.58-1.80） than those of modern shallow seawater （0.2.-0.50） suggests complicated sources of REEs for all samples. Compared with geochemical features of sediments influenced by terrigenous particles and hydrothermal fluids, it is concluded that ambient shallow seawater was the primary source of REEs in these limestones. Comparing the indicators of REE＋Y elements （ZREE, NdsN/YbsN, Ce/Ce＊, Gd/Gd＊, Eu/Eu＊ and Y/Ho） in limestones with those in bedded cherts from the Tieqiao section, we consider that limestone and bedded chert have similar sources of REE＋Y elements： ambient shallow seawater with more or less hydrothermal fluids. In addition, there is a completely negative correlation between CaCO3.and SiO2.contents in limestones and bedded cherts. These results imply that precipitation of CaCO3.was inhibited by that of SiO2.which was derived mainly from hydrothermal fluid, es- pecially in bedded cherts from the Tieqiao section.

关键词： geochemistry rare earth element limestone the Middle to Late Permian South China

Intense,wideband optical waveform generation by self-balanced amplification of fiber electro-optical sideband modulation

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Chinese Optics Letters 2022年第11期20卷 31-37页

作者： yuzhuo Wang Yizun He Lingjing Ji Jiangyong Hu Xing Huang Yudi Ma Liyang qiu Kaifeng Zhao Saijun Wu Department of Physics State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures(Ministry of Education)Fudan UniversityShanghai 200433China Key Laboratory of Nuclear Physics and Ion-Beam Application(Ministry of Education) Fudan UniversityShanghai 200433China institute of Modern Physics Department of Nuclear Science and TechnologyFudan UniversityShanghai 200433China

We demonstrate a simple method to obtain accurate optical waveforms with a gigahertz-level programmable modulation bandwidth and a watt-level output power for wideband optical control of free atoms and *** amplitude and phase modulations are transferred from microwave to light with a low-power fiber electro-optical *** sub-milliwatt optical sideband is co-amplified with the optical carrier in a power-balanced fashion through a tapered semiconductor amplifier(TSA).By automatically keeping TSA near saturation in a quasi-continuous manner,typical noise channels associated with pulsed high-gain amplifications are efficiently *** an example application,we demonstrate interleaved cooling and trapping of two rubidium isotopes with coherent nanosecond pulses.

关键词： pulse shaping laser cooling and trapping high gain optical pulse amplification self-phase modulation amplified spontaneous emission sideband modulation

贵州省典型铅锌矿区和贵阳市居民汞暴露以及健康风险评估

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生态学杂志 2024年第3期43卷 869-877页

作者：王达卫孔林徐晓航韩佳良刘杰民仇广乐中国科学院地球化学研究所环境地球化学国家重点实验室贵阳550081 中国科学院大学北京100049 贵州医科大学公共卫生学院环境污染与疾病监控教育部重点实验室贵阳550025 贵州省人民医院贵阳550025

选择贵州省赫章县铅锌矿区和贵阳市居民区,采集了居民日用食物(大米、土豆、鸡蛋、蔬菜、鱼肉、猪肉)、饮用水和农作物根际土壤,共计503.,测定了总汞和甲基汞的含量,并结合蒙特卡洛模拟评估了居民无机汞和甲基汞暴露风险。结果如下:(1... 详细信息

选择贵州省赫章县铅锌矿区和贵阳市居民区,采集了居民日用食物(大米、土豆、鸡蛋、蔬菜、鱼肉、猪肉)、饮用水和农作物根际土壤,共计503.,测定了总汞和甲基汞的含量,并结合蒙特卡洛模拟评估了居民无机汞和甲基汞暴露风险。结果如下:(1)铅锌矿区的样品总汞和甲基汞的范围分别为0.11~3.和0.02.~1.7 ng·g^(-1),城市居民区的样品总汞和甲基汞的范围分别为0.07~18和0.01~7.7 ng·g^(-1),除蔬菜外的样品总汞含量低于我国食品限量标准,蔬菜总汞含量分别有14.7%(铅锌矿区)和17.7%(城市居民区)的样品超过我国《食品安全国家标准》(GB 2.72.2.17)规定的10 ng·g^(-1)。(2.两个地区无机汞日暴露量无差异(城市居民区:0.03.μg·kg^(-1)·d-1,铅锌矿区:0.03.0}g·kg^(-1)·d-1),但城市居民区的甲基汞日暴露量(0.006μg·kg^(-1)·d-1)高出铅锌矿区(0.003.0}g·kg^(-1)·d-1)近1倍。(3.两个地区居民无机汞和甲基汞的平均日暴露量分别低于联合国粮农组织/世界卫生组织食品添加剂联合专家委员会(JECFA)推荐的人体安全无机汞的临时容许每周摄入量(PTWI)4μg·kg^(-1)·week-1和美国环境保护署(USEPA)推荐的甲基汞参考剂量(RfD)0.1μg·kg^(-1)·d-1,暴露风险指数均小于1,表明处于健康安全水平。

关键词：铅锌矿区贵阳市居民区无机汞甲基汞风险评估