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geochemistry and zircon U-Pb ages of the Oligocene sediments in the Baiyun Sag, Zhujiang River Mouth Basin

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Acta Oceanologica Sinica 2021年第2期40卷 123-135页

作者： Rui Sun Ming Ma Kai Zhong Xiayang Wang Zhao Zhao Shuai Guo Xingzong Yao Gongcheng Zhang State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Key Laboratory of Petroleum Resources Gansu ProvinceLanzhou 730000China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China CNOOC Research Institute Co. Ltd.Beijing 100028China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China Research Institute of Petroleum Exploration&Development PetroChinaBeijing 100083China Department of Geology Northwest UniversityXi’an 710069China

In this study,element geochemistry and zircon chronology are used to analyze the Oligocene sediments in the Baiyun Sag,Zhujiang River Mouth *** experimental results are discussed with respect to weathering conditions,parent rock lithologies,and *** chemical index of alteration and the chemical index of weathering values of mudstone samples from the lower Oligocene Enping Formation indicate that clastic particles in the study area underwent moderate *** samples exhibit relatively enriched light rare earth elements and depleted heavy rare earth elements,"V"-shaped negative Eu anomalies,and negligible Ce *** rare earth element distribution curves are obviously right-inclined,with shapes and contents similar to those of post-Archean Australian shale and upper continental crust,indicating that the samples originated from acid rocks in the upper *** Hf-La/Th and La/Sc-Co/Th diagrams show this same origin for the sediments in the study *** the samples from the upper Enping deltas,the overall age spectrum shows four major age peaks ca.59–68 Ma,98–136 Ma,153–168 Ma and 239–260 *** the Zhuhai Formation samples,the overall age spectrum shows three major age peaks ca.149 Ma,252 Ma and 380 *** detrital zircon shapes and U-Pb ages reveal that during Oligocene sedimentation,the sediments on the northwestern margin of the Baiyun Sag were supplied jointly from two provenances:Precambrian-Paleozoic metamorphic rocks in the extrabasinal South China fold zone and Mesozoic volcanic rocks in the intrabasinal Panyu Low Uplift,and the former supply became stronger through ***,the provenance of the Oligocene deltas experienced a transition from an early proximal intrabasinal source to a late distal extrabasinal source.

关键词： weathering degree lithology of parent rock provenance element geochemistry zircon U-Pb ages Baiyun Sag

geochemistry of Soil Formation in Sonth China SeaIslands

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Pedosphere 1995年第4期5卷 334-342页

作者： GONGZI－TONG HUANGBIAO InstituteofSoilScience AcademiaSinicaNanjing210008China InstituteofSoilScience AcademiaSinicaNanji

The soils in the South China Sea Islands (SCSI) were divided into three types, namely, phospho-calc soils,skeletisols and coastic solonchaks, which were derived from bio-clastic and strongly calcareous sediments. Incomparison with their parent materials, the phospho-calc soils have higher contents of P, Zn, Cu, Ba, and Cd,which tend to increase gradually with time, and lower contents of Mg, Ca, Sr, B, V, Pb, and Mo, which tendto decrease by degrees with time. The above-mentioned constitnents in skeletisols and coastic solonchaks aresimilar to those in their parent materials except for P and Na. The factors atfecting element distribution aremainly special bioclimate and parent material, meanwhile, resulting in the remarkable iulluence on elementdistribution through soil-forming time.

关键词： element geochemistry soils South China Sea Islands

element and mineral characterization of dust emission from the saline land at Songnen Plain, Northeastern China

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Journal of Environmental Sciences 2009年第10期21卷 1363-1370页

作者： CHEN Bing KITAGAWA Hiroyuki HU Ke JIE Dongmei YANG Junpeng LI Jingmin Department of Hydrospheric-Atmospheric Sciences Graduate School of Environmental Studies Nagoya University Nagoya 464-8601 Japan. Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China College of Earth Sciences Jilin University Changchun 130061 China School of Marine Science China University of Geosciences Beijing 100038 China College of Urban and Environmental Sciences Northeast Normal University Changchan 130024 China

Recent observations of Asian dust storms show an eastern expansion of the source area to degraded lands, where dust emissions have been little studied. The dust concentrations over the saline land of the western Songnen Plain （SSL）, Northeastern China, are circumstantially higher than those from the northwestern Chinese deserts. These concentrations are sensitive to the surface soil conditions and wind velocity on the ground. The dust samples collected during dust storm events on the SSL contain abundant Na, Mg, A1, K, Ca, Fe and Ti, as well as toxic elements such as Cu, V, Zn and Ba. Individual particle analysis reveals that fine saline particles （〈 10 μm in diameter） on the saline land, consisting largely of carbonate, halite and sulfate together with lithogenic minerals such as SiO2 and aluminosilicate, are eventually uplifted during the interval from spring to autuum. The predominantly fine saline particles uplifted from the SSL are likely transported eastward by the winter monsoon circulation and westerlies. Recent degradation of saline lands in Northeastern China would not only increase the frequency of dust storm events in the downwind area, but also might change the chemical composition of the Asian dust emissions.

关键词： element geochemistry individual particle analysis Asian dust dust storm saline soil land degradation

Influence on lacustrine source rock by hydrothermal fluid： a case study of the Chang 7 oil shale, southern Ordos Basin

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Acta Geochimica 2018年第2期37卷 215-227页

作者： Delu Li Rongxi Li Zengwu Zhu Xiaoli Wu Futian Liu Bangsheng Zhao Baoping Wang School of Earth Sciences and Resources Chang'an University Xi'an 710054 China Shaanxi Center of Geological Survey Xi'an 710068 China Yanchang Oilfiled Co. Ltd Yan'an 716000 China

Hydrothermal fluid activity during sedimenta- tion of the Triassic Yanchang Formation in the Ordos Basin and the impact of said activity on formation and preservation conditions of source rocks have received little attention. Oil yield, major element, trace element, rare earth element, and total sulfur （TS） data from the oil shale within the Yanchang are here presented and discussed in the context of hydrothermal influence. Oil shale samples returned relatively high total organic carbon （TOC）, in the range of 4.69%-25.48%. A high correlation between TS and TOC suggests TS in the oil shale is dominated by organic sulfur and affected by organic matter. The low Al/ Si ratio of oil shale samples implies quartz is a major mineralogical component. Si/（Si ＋ Al ＋ Fe） values suggest close proximity of the oil shale to a terrigenous source. δEu; Fe versus Mn versus （Cu ＋ Co ＋ Ni）× 10; and SiO2/（K2O ＋ Na2O） versus MnO/TiO2, Fe/Ti, and （Fe ＋ Mn）/Ti are evidence of hydrothermal fluid activity during oil shale sedimentation, and δU and U/Th of the oil shale indicate reducing conditions. The Sr/Ba of oil shale samples suggests fresh-water deposition. The high correlations of Fe/Ti and （Fe ＋ Mn）/Ti with δU, U/Th, and TS demonstrate that hydrothermal fluid activity promotes reducing conditions. Sr/Ba ratios had low correlation with Fe/Ti and （Fe ＋ Mn）/Ti, implying that hydrothermal fluid activity had little impact （Fe ＋ Mn）/Ti, δU, U/Th, and on paleosalinity. Fe/Ti, Cu ＋ Pb ＋ Zn all exhibited high positive correlation coefficients with TOC in oil shale samples, suggesting that more intense hydrothermal fluid activity improves conditions in favor of formation and preservation of organic matter.

关键词： Hydrothermal fluid activity Lacustrine source rock element geochemistry Chang 7 Ordos Basin

Geochemical Study of Gold and Arsenic Mineralization of the Carlin-Type Gold Deposits, Qinling Region, China

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Acta Geochimica 2001年第4期20卷 333-342页

作者：张复新马建秦陈衍景 The Key Lab. of Continental Dynamics Northwest University Ministry of Education Xi’an China Department of Geology Northwest University Xi’an China Institute of geochemistry Chinese Academy of Sciences Guiyang China Department of Geology Peking University Beijing China

element geochemistry of gold and arsenic and mineralogical features of their sulfides in the Carlin-type gold deposits of the Qinling region are discussed in this paper. The initial contents of ore-forming elements such as gold and arsenic are high in the ore-bearing rock series in the Qinling region. Furthermore, both the metals are concentrated mainly in the diagenetic pyrite. Study on the mineralogy of arsenic-bearing sulfide minerals in the ores demonstrated that there is a positive correlation between gold and arsenic in the sulfide minerals. Available evidence suggests that gold in the As-bearing sulfide minerals is likely to be presented as a charge species (Au+), and it is most possible for it to replace the excess arsenic at the site of iron and was probably deposited together with arsenic as solid solution in the sulfide minerals. Pyrite is composed of (Au 3+ x, Fe 2+ 1-x) ( 3- x 2- 1-x), and arsenopyrite of (Au 3+ x, Fe 3+ 1-x) ( 3- x 3- 1-x). The occurrence of gold in the As-sulfide minerals from the Carlin-type gold deposits in the Qinling region has been confirmed by electron probe and transmission electron microscopic studies. The results show that gold was probably deposited together with arsenic as coupled solid solutions in sulfide minerals in the early stage of mineralization.. Metallogenic chemical reactions concerning gold deposition in the Carlin-type As-rich gold deposits would involve oxidation of gold and concurrent reduction of arsenic. Later, the deposited gold as solid solution was remobilized and redistributed as exsolutions, as a result of increasing hydrothermal alteration and crystallization, and decreasing resistance to refractoriness of the host minerals. Gold occurs as sub-microscopic grains (ranging from 0.04 to 0.16 μm in diameter) of native gold along micro factures in and crystalline grains of the sulfides.

关键词： gold arsenic element geochemistry Carlin-type gold deposit Qinling region

Geochemical characteristics of Guizhou Permian coal measure strata and analysis of the control factors

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Journal of Coal Science & Engineering(China) 2011年第1期17卷 55-68页

作者： YANG Rui-dong LIU Ling WEI Huai-rui CUl Yu-chao CHENG Wei College of Resources and Environment Guizhou University Guiyang 550025 China Guizhou Nonferrous Metal Geological Exploration Bureau Guiyang 550001 China Shangdong Coal Geological Exploration Bureau Taian 271000 China

Based on element geochemical studies of the main Permian exploitable coal measure strata in Western Guizhou, the element geochemical distribution characteristics of the main exploitable coal measures were revealed in the regions of Dafang, Qianxi, Weining, Hezhang, Zhijin, etc., of Guizhou Province, and the results show that their element contents are mainly affected by terrestrial material supply. Coal measures formed in the delta plain environment where sufficient terrestrial materials are supplied contain relatively abundant trace elements and rare-earth elements, whereas those formed in the tidal-fiat environment influenced greatly by seawater have relatively low contents of trace elements and rare-earth elements, mainly con- trolled by the geological fact that basalts the parent rocks from source regions contain high trace elements and rare-earth elements. In addition, coal measures affected by later hydrothermal activities and fault tectonics contain a large amount of harmful elements. According to the rules of distribution of elements in coal measures, a new idea was put forward to classify coal-forming environments by using the geochemical composition characteristics, which is of great significance in dissolving the problem of whether coal measures were fbrmed either in delta environments or in tidal-flat environments in Western Gui- zhou. At the same time, the rules of distribution of elements in the main exploitable coal measures in Western Guizhou were fully understood, which is of direct significance in utilizing coal resources on the basis of classification of coals, as well as in developing the coal chemical industry.

关键词： element geochemistry sedimentary environment major exploitable coal measures Permian Western Guizhou

Geochemical records of the sediments and their significance in Dongping Lake Area,the lower reach of Yellow River,North China

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Journal of Groundwater Science and Engineering 2021年第2期9卷 140-151页

作者： Lin-song Yu Hong-bo Liu Fang Wan Zun-fang Hu Huai-dong Luo Xiu-wen Zhang Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu Universtity of TechnologyChengdu 610059China College of Earth Sciences Chengdu University of TechnologyChengdu 610059China Shandong Institute of Geophysical and Geochemical Exploration Jinan 250013China

Dongping Lake area,located in the lower reaches of Yellow River,is an ideal place to study the changes of modern river and lake sedimentary *** sediment samples of Dawen River,Yellow River,and Dongping Lake were collected,and the major elements,trace elements and organic matter geochemical composition of the samples were *** analysis,characteristic element ratio method and graphic method were used to explore the geochemical characteristics of sediments and their environmental *** results show that the contents of SiO_(2),Na_(2)O,TiO_(2) and Zr in sediments of Dawen River and Yellow River are relatively high,and the contents of iron and manganese oxides,organic matter,CaO,P2O5 and Sr in lake sediments are relatively *** reveals the differences of sedimentary environments between the rivers and the *** contents of Sr and Zr in Dawen River are affected by the rapid migration of clastic materials in the upstream carbonate source area during the flood season;the δCe,ΣREE and REE’s ratios in the sediments of the Yellow River reflect the influence of the Loess source;and the distribution of elements changes along the flow direction during the flood *** characteristics of pH,element composition and LREE&HREE fractionation of the lake sediments indicate that the sediment source is complex,and the lake environment is affected by the flood *** study shows that the geochemical content and its variation characteristics of sediments effectively reveal the sedimentary environment,material composition and characteristics of flood season of rivers and the lake in the study area.

关键词： Dongping Lake Yellow River Sediments Organic matter element geochemistry

geochemistry and Sr-Nd-Pb-Hf isotopes of Early Cretaceous basalts from the Great Xinggan Range,NE China:Implications for their origin and mantle source characteristics

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Geochemistry and Sr-Nd-Pb-Hf isotopes of Early Cretaceous ba...

Genesis of Qujiashan manganese deposit, Shaanxi Province: constraints from geological, geochemical, and carbon and oxygen isotopic evidences

中国科学院地质与地球物理研究所2008学术年会

作者： Lian-chang Zhang~(a,*),Xin-hua Zhou~b,Ji-feng Ying~b,Fei Wang~b,Feng Guo~c,Bo Wan~a,Zhi-guang Chen~a a Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences,P.O.BOX 9825,Beijing 100029,China b State Key Laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China c Guangzhou Institute of geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China

Late Mesozoic volcanism is widespread throughout northeastern China,mainly clustering in the Great Xinggan Range,where the major period of volcanic eruption was during the Early *** spatial distribution of volcanic rocks shows a NNE-extending *** lithology of Mesozoic basaltic rocks in the Great Xinggan Range ranges from trachytic basalts,basalts to basaltic *** the basis of lithological associations and spatial relationships,we divide the basalts into four groups,***,Genhe,Zalute and *** Early Cretaceous volcanism in the Great Xinggan Range is characterized by significant large ion lithophile elements(LILE) and light rare earth elements(LREE) enrichment and high field strength elements(HFSE) depletion,with a slightly enriched to depleted Nd-Hf and weakly enriched Sr isotopic compositions(initial Sr/Sr=0.7046-0.7079,ε(t)=+3,6 to - 6.9 andε(t)=+3.9 to -4.6).The Pb isotopic compositions are also variable with Pb/Pb,Pb/Pb and Pb/Pb values of 17.791-18.530,15.477-15.597 and 37.761-38.497,*** Sr-Nd-Pb-Hf isotopic data indicate that the rnagmatic sources are heterogeneous,showing an enriched to depleted signature of continental lithospheric *** rnagmatic sources of the Genhe and Zalute groups are characterized by mixing among PM,EM II and DM,whereas the Tahe and Xiwu groups derive from enriched lithospheric mantle that had experienced metasomatism by fluids or melts from subducted Paleo-Asian and Mongol-Okhotsk ocean slabs and possible influence of Precambrian *** Late Mesozoic volcanic rocks in the Great Xinggan Range resemble those of the Cenozoic calc-alkaline magmatism in the Basin and Range Province of the United *** therefore suggest that the widespread Mesozoic volcanic rocks in the Great Xinggan Range were generated in an extensional tectonic setting.

关键词： element geochemistry Sr-Nd-Pb-Hf isotope Basaltic rocks Early Cretaceous Extensional setting Great Xinggan Range NE China

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Journal of Central South University 2019年第12期26卷 3516-3533页

作者： WANG Zi-yong HAN Run-sheng REN Tao WU Yong-tao LI Hu-jie Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming 650093China College of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China

The Qujiashan manganese deposit is located in the Longmen-Daba fold belt along the northern margin of the Yangtze Block. The layered ore bodies are distributed within the purple-red calcareous shale. Qujiashan is a high-grade w(MnO)=8.92% to 18.76%) manganese deposit with low-phosphorus w(P2O5)=0.08% to 0.16%) content. It also has a low total REEs contents(with an average of 101.3×10-6), and has inconspicuous Ce(0.81 to 1.29) and Eu(1.00 to 1.25) anomalies. lg(Ce/Ce*) values are from-0.02 to 0.11. The ores have high SiO2/Al2O3 and Al/(Al + Fe + Mn) ratios. In figures of Fe–Mn–[(Ni+Cu+Co)×10] and lgU–lgTh, all samples show that hydrothermal exhalative fluids played an important role during mineralisation. The δ13CPDB and δ18OSMOW values of eight ore samples are from-20.7‰ to-8.2‰(with an average of-12.4‰) and from 14.3‰ to 18.7‰(with an average of 17.0‰), respectively. These carbon and oxygen isotopic features indicate that hydrothermal fluids derived from deep earth are participation in the metallogenic process, which is also supported by high paleo-seawater temperatures varying from 47.08 to 73.98 °C. Therefore, the geological and geochemical evidences show that the Qujiashan deposit formed from submarine exhalative hydrothermal sedimentation.

关键词： manganese deposit element geochemistry carbon and oxygen isotopes genesis Qujiashan manganese deposit