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Using Geochemistry of Rare Earth Elements to Indicate Sediment Provenance of Sand Ridges in Southwestern Yellow Sea

Chinese Geographical Science 2017年第1期27卷 63-77页

作者： LI Lei SU Jinbao rao wenbo WANG Yigang College of Earth Sciences and Engineering Hohai University Nanjing 210098 China College of Harbour Coastal and Offshore Engineering Hohai University Nanjing 210098 China

The Jianggang Harbour-centered radial sand ridge(RSR) is the largest sand body in the Yellow Sea. Its formation and evolution are of interest for scientists of various fields; however, the sediment provenance is uncertain. In this study, rare earth element(REE) geochemical compositions of the RSR sediments together with their potential sources are investigated to identify the provenance of the RSR sediments. The typical parameters((La/Yb)_N,(La/Sm)_N and(Gd/Yb)_N) as well as the upper continental crust-normalized patterns of REEs can only be associated with source rocks, and thus can be used as effective tracers for the origin and sources of sediments. However, the REE contents of sediments are affected by many factors, such as particle sorting and chemical weathering. Onshore RSR sediments are different in REE geochemical composition from offshore RSR sediments to some extent, suggesting that not all of the offshore RSR sediments have the same sources as the onshore RSR sediments. Meanwhile, the sediments adjacent to the northeast of Cheju Island and at Lian Island near the Lianyun Harbour were not the source of the RSR sediments due to their distinctive REE patterns, dEu,(La/Yb)_N,(Gd/Yb)_N and(La/Sm)_N. The Korean river sediments could be dispersed to the Jiangsu Coast slightly impacting the fine fractions of the RSR sediments, particularly the offshore RSR sediments. Additionally, geochemical comparisons show that the modern Yellow River was responsible for the onshore RSR sediments, whereas the sediment loads from the Yangtze River could serve as a major contributor to the RSR, particularly the offshore RSR. In addition, the offshore RSR could also be partly fed by an unknown source due to some high values of(La/Yb)_N,(La/Sm)_N and La contents differing from those of the Chinese and Korean river sediments.

关键词： rare earth elements(REEs) sediment provenance radial sand ridges(RSRs) potential sources Yellow Sea

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Detrital Zircon Geochronology of the Radial Sand Ridge System of Jiangsu Coast, East China: Implication for Sediment Provenance

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Journal of Earth Science 2018年第1期29卷 144-154页

作者： Jinbao Su wenbo rao Yigang Wang Changping Mao School of Earth Sciences and Engineering Hohai University School of Harbour Coastal and Offshore Engineering Hohai University

The radial sand ridge system （RSRS） located at Jiangsu coast of China attracts much attention on its origin and mechanic of formation for its special structure and potential land resource. Due to complicated hydrodynamic condition, the Jiangsu RSRS is a hot debated on its potential sources, Yangtze River or Yellow River？ We collected ten sand samples from surface sediments along the west coast of Bohai Sea and Yellow Sea from the modern Yellow River estuary to Yangtze River estuary in summer, 2013. The samples are analyzed by method of detrital zircon age for source identification of the RSRS sediments. The U-Pb age spectra of detrital zircon grains of the samples show a wide range from Cenozoic to Late Archean with several age peaks. Comparing the age spectra between the Yangtze River and the Yellow River, the detrital zircons have younger age （〈100 Ma） group in the Yangtze River. These age distribution of the Jiangsu coastal RSRS sediments are similar to that of the Yangtze River, but different from the Yellow River. The samples located adjacent to the old Yellow River Delta show more wide-range age distribution, implying a compounded origination from the both rivers. Based on these findings it is proposed that, contrary to common opinion, the main sediment source of the Jiangsu RSRS is the Yangtze River, rather than the Yellow River. By implication, there should be evidence of hydrodynamic mechanics of oceanic currents and tidal motion. This aspect awaits confirmation in future research.

关键词： Yellow Sea Jiangsu coast radial sand ridge zircon geochronology sediment provenance.

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Sr-Nd isotope geochemistry of eolian dust of the arid-semiarid areas in China: Implications for loess provenance and monsoon evolution

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Chinese Science Bulletin 2006年第12期51卷 1401-1412页

作者： rao wenbo YANG Jiedong CHEN Jun LI Gaojun Department of Earth Sciences Nanjing University Nanjing 210093 China

Minerals and rocks have distinct 87Sr/86Sr and 143Nd/144Nd ratios, depending on their geological origin and ages, and these isotope ratios are less altered than elemental composition during transport in the atmosphere or after deposition as sediments, thus stable isotopes of Sr and Nd have great potential as tracers for provenance and trans- port of materials. During the hypergene process, Sr isotope ratios of sediments are controlled by their parent rocks, particle sizes and chemical weathering. In general, the higher the Sr isotope ratios of parent rocks, and/or the more the fine-grained fractions, and/or the stronger the chemical weathering, thus the higher the Sr isotope ratios of sediments. On the contrary, there are lower Sr isotope ratios of sedi- ments. Nd isotope ratios of sediments, independent of their particle sizes and chemical weathering, are only associated with parent rocks. For the prove- nance of the Chinese Loess Plateau, different re- seachers drew discordant and even contradictory conclusions by using the method of Sr-Nd isotopic tracing. From the previous Nd isotope data, it is con- sidered that the Tarim Basin, deserts in the central and west parts of Inner Mongolia and the Tibetan Plateau are the main sources of the Chinese Loess Plateau, and are also manufacturers for eolian dust of the Far East regions, together with the Chinese Loess Plateau. Sr isotope ratios of eolian dust are solely affected by wind sorting and weather- ing-pedogenesis due to its homogeneous composi- tion in the Chinese Loess Plateau. Wind sorting isrelated to the East Asian winter monsoon but weath- ering-pedogenesis is mainly associated with the East Asian summer monsoon. Studies on Sr isotopic compositions of the loess-paleosol sequence suggest that 87Sr/86Sr ratios in acid-soluble materials are an index for chemical weathering intensity of the Chi- nese Loess Plateau, indicating the East Asian sum- mer monsoon variations, whereas 87Sr/86Sr ratios in acid-insoluble m

关键词：锶-钕同位素季风黄土干旱-半干旱地区地球化学

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Geochemical constraints on seasonal recharge of water and major dissolved solutes in the Huangshui River,China

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Chinese Journal Of Geochemistry 2012年第2期31卷 155-164页

作者： TAN Hongbing ZHOU Huifang rao wenbo ZHANG Wenjie KONG Na School of Earth Sciences and Engineering Hohai University Nanjing 210098 China

The Huangshui River,an important tributary in the upper reaches of the Yellow River,has been regarded as a mother river which gestates Qinghai civilization in *** paper presents the results of hydrogen and oxygen isotopic and water chemical analyses for the summer and winter Huangshui River water to study its seasonal recharge and major dissolved *** of hydrogen and oxygen isotopes suggest that precipitation in the Qilian Mountains is the original recharge of the Huangshui ***,in winter,the basic flow of the Huangshui River only depends on spring recharge and spring water originates from melt and infiltration of bottom layer *** summer,besides spring water,much rainfall directly recharges the Huangshui River,thus making its flux increase *** chemistry shows that the processes affecting dissolved solutes in the Huangshui River are also different between summer and *** summer,major ions in the river water are dominantly derived from carbonate and evaporate dissolution and anthropogenic *** winter,carbonate dissolution decreases greatly while anthropogenic inputs play a much more important role for dissolved solutes in the ***,further measures should be taken to lay stress on the winter Huangshui River water in order to protect the environment of the Huangshui River and reduce effects of dissolved solutes on,or prevent their pollution toward the upper Yellow ***,some measures also need to be introduced to prevent the possibility of water eutrophication caused by agricultural activities or stock raising in summer.

关键词：碳酸盐溶解湟水河补给水地球化学制约季节性溶质中国水化学分析

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Chemical and Isotopic Approach to Groundwater Cycle in Western Qaidam Basin,China

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Chinese Geographical Science 2009年第4期19卷 357-364页

作者： TAN Hongbing rao wenbo CHEN Jiansheng SU Zhiguo SUN Xiaoxu LIU Xiaoyan State Key Laboratory of Hydrology- Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Department of Earth Science and Engineering College of Civil Engineering Hohai University Nanjing 210098 China

Due to the extremely arid climate in the western Qaidam Basin,the groundwater almost becomes the single water source for local residents and industrial *** is necessary to know the reliable information on the groundwater cycle in this region for reasonable and sustainable exploitation of the groundwater resources with the further execution of recycling economy *** study focused on the recharge,the flow rate and the discharge of groundwater in the western Qaidam Basin through investigations on water chemistry and ***,chemical and isotopic characteristics show that the groundwater in the western Qaidam Basin was recharged by meltwater from new surface snow and old bottom glaciers on the northern slope of the Kunlun *** addition,the results also prove that the source water is enough and stable,and the rates of the circulation and renewal of the groundwater are relatively ***,it can be concluded that the groundwater resources would guarantee the regional requirement if the meltwater volume of the mountains has not a great changes in future,moreover,water exploitation should be limited to the renewable amount of the groundwater reservoir in the western Qaidam Basin.

关键词： groundwater cycle water chemistry isotope Qaidam Basin

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Formation mechanisms of megadunes and lakes in the Badain Jaran Desert,Inner Mongolia

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Chinese Science Bulletin 2006年第24期51卷 3026-3034页

作者： CHEN Jiansheng ZHAO Xia SHENG Xuefen DONG Haizhou rao wenbo SU Zhiguo State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Isotope Hydrology Institute of Hohai University Nanjing 210098 China Geotechnical Research Institute of Hohai University Nanjing 210098 China

Field observations demonstrate that calc-sinters occurred in the lakes of Badain Jaran Desert. 87Sr/86Sr ratios,14C,δ 13C and mineral com-positions of calc-sinters,and 3He/4He,4He/20Ne,δ 18O,δ D,pH and TDS of water from springs and lakes are analyzed in detail. The results indicate that the lake water is supplied through deep fault zone. The “ker-nel” of stabilized dunes in the Badain Jaran Desert perhaps consists of calc-sinters and calcareous ce-mentation layers. Deep-seated groundwater effuses from this “kernel” and recharges to lakes in desert. Precipitation and snowmelt water from the Qing-hai-Tibet Plateau is fed into the Badain Jaran Desert,Gurinai,Wentougaole and Ejinqi areas through the Xigaze-Langshan Fault zone. The isotopic composi-tions of groundwater in the Alax Plateau are abnor-mal due to the strong evaporation of the Gyaring and Ngoring lake water in the headstream of the Yellow River. Groundwater dissolves dissoluble fractions of rocks during its transportation through the fault zone and flows out of the mouth of spring in the Badan Jaran Desert. The dissoluble fractions are finally de-veloped into calc-sinters and calcareous cementation layers around the spring. Calci-sinters are gradually largened and eventually emerge on the surface of lake water. Eolian sands accumulate on the surfaces of calc-sinters and calcareous cementation layers,and eventually develop into dunes. Invasion of magma causes an increase in the temperature of groundwater within the faults. Groundwater evapora-tion provides water vapor for the formation of humid stabilized dunes during its upwelling. Rhizoconcre-tions found in Yihejigede indicate that the dune was formed and remained immovable 4700 years ago. The height of the megadunes is proportional to thermal quantity carried by the groundwater.

关键词：内蒙古沙漠湖泊泉水泉华断裂带地下水同位素成分形成机制

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Study on the mechanism of isotope fractionation in soil water during the evaporation process under equilibrium condition

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Chinese Journal Of Geochemistry 2009年第4期28卷 351-357页

作者： SUN Xiaoxu CHEN Jiansheng TAN Hongbing rao wenbo WANG Yongsen LIU Xiaoyan SU Zhiguo State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China Reserch Institute of Science and Technology Hohai University Nanjing 210098 China

In this study, with the method of vacuum extraction, two evaporative processes of soil water and free water under equilibrium condition were simulated. For each sample,water vapor was condensed by liquid nitrogen and was collected in four time intervals. From the analysis of hydrogen and oxygen isotopic compositions of the water collected at different times, it was discovered that the isotope fractionation of soil water also follows the mode, which is just the same as the evaporative process of free water. The relationship between the stable hydrogen and oxygen isotopes in residual water showed that the simulative evaporation line was close to the global meteoric water line (GMWL) under the equilibrium condition at about 20℃. Comparison of the two types of evaporative processes indicated that the isotope fractionation and evaporation velocity of soil water were only slightly modified by the Van der Waals force.

关键词：氧同位素分析土壤水分平衡条件工艺条件水蒸发分馏机理同位素分馏水汽凝结

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Gold redistribution in Shangmanggang red-clay gold deposit, western Yunnan Province, China

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Chinese Science Bulletin 1999年第S2期44卷 214-216页

作者： YANG Zhusen, LI Hongyang, GAO Zhenmin, LUO Taiyi, rao wenbo and DING Zhenju Open Laboratory of Deposit Geochemistry, Iustitute of Geoehemistry, Chinese Academy of Sciences, Guiyang 550002, China Open Laboratory of Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

AFTER the discovery of lateritic gold deposits in the world during the 1980s, many similar oxidized golddeposits have been discovered in southern China since 1989. Because the incomplete lateritization ofthe regolith compared with the laterite, these oxidized gold deposits were called the red-clay type gold deposits by Prof. Tu Guangzhi. The Shangmanggang gold deposit is a typical representative of the red-claytype gold deposit in western Yunnan Province. 1 Geology, climate, and geomorphology The Shangmanggang red-clay gold deposit is located in Luxi region, between Zhefang and LuxiCenozoic basins along the Longling-Runli Fault trending northeast. The northwestern flank of the basinsconsists of the Proterozoic Gaoligong Group composed of greenschist to amphibolitic metamorphic

关键词： gold redistribution red-clay type of gold deposit Shangmanggang gold deposit Yunnan.

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三峡库区沉积物还原性无机硫形态的分布特征、控制因素及对内源磷释放的影响

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湖泊科学 2023年第2期35卷 460-472,I0004页

作者：王耀茅昌平贾志敏王帅饶文波河海大学地球科学与工程学院南京211100 黄河生态环境科学研究所郑州450003

还原性无机硫(RIS)包括硫酸盐还原产物和活性铁(FeHR)形成的酸可挥发性硫(AVS)、硫的中间产物元素硫(S0)及沉积物中硫铁元素的最终积累物质黄铁矿硫(Spy),RIS不仅可以影响沉积物重金属的生物有效性,还控制铁还原及内源磷的释放等生源要... 详细信息

还原性无机硫(RIS)包括硫酸盐还原产物和活性铁(FeHR)形成的酸可挥发性硫(AVS)、硫的中间产物元素硫(S0)及沉积物中硫铁元素的最终积累物质黄铁矿硫(Spy),RIS不仅可以影响沉积物重金属的生物有效性,还控制铁还原及内源磷的释放等生源要素的地球化学行为。为了研究三峡库区沉积物中RIS分布特征及其环境意义,于2017年7—8月和12月采集三峡库区云阳至秭归段17个点的表层沉积物样品并测定其RIS含量。结果表明:与其他湖泊、河流相比,三峡库区表层沉积物RIS含量较低,其中,AVS的含量为0.06~0.65μmol/g,S0为0.50~1.66μmol/g,Spy为0.96~17.54μmol/***和S0含量夏季高于冬季,云阳至秭归段RIS变化趋势大致为先降低后增加再降低,有较明显的季节和地域差异。相关性分析、主成分分析和聚类分析表明,研究区沉积物生物可利用磷(BAP)、FeHR及上覆水体SO42-含量为沉积物RIS的主要限制因子。库区冬季RIS与有机磷(Org-P)和可交换态磷(Ex-P)呈显著相关性,当硫化物含量增加时,会促进Org-P的矿化分解和Ex-P向上覆水体迁移,增加释磷风险。同时,本研究从硫驱动富营养化的角度评估了三峡库区存在污染风险的水域。除库区内已发生过典型水华的重点支流外,长滩河和九畹溪也存在富营养化问题。

关键词：三峡库区表层沉积物还原性无机硫形态影响因素硫铁磷耦合关系

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江苏沿海沙脊群表层沉积物Pb同位素特征及对物源的指示

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河海大学学报（自然科学版） 2024年第2期52卷 84-91页

作者：饶文波洪申申栗天宁茅昌平河海大学地球科学与工程学院江苏南京211100

为进一步查明江苏沿海沙脊群沉积物的来源,分析了该区域沉积物酸不溶组分Pb同位素特征。结果表明,远岸沙脊群陆向区域沉积物Pb同位素比值与近岸沙脊群相似,暗示其在潮波作用下有向岸运移的趋势。铅钕同位素分析揭示长江及周边河流沉积... 详细信息

为进一步查明江苏沿海沙脊群沉积物的来源,分析了该区域沉积物酸不溶组分Pb同位素特征。结果表明,远岸沙脊群陆向区域沉积物Pb同位素比值与近岸沙脊群相似,暗示其在潮波作用下有向岸运移的趋势。铅钕同位素分析揭示长江及周边河流沉积物在长江冲淡水和东海沿岸流作用下输移至远岸沙脊群海向区域。在苏北沿岸流作用下,老黄河三角洲沉积物输入对近岸沙脊群及远岸沙脊群陆向区域有影响;相反,诸如现代黄河口、济州岛和韩国河流等地沉积物输入对江苏沿海沙脊群的影响较弱。

关键词：铅同位素物质来源表层沉积物沙脊群江苏沿海

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