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major elements in the Holocene loess-paleosol sequence in the upper reaches of the Weihe River valley,China

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Journal of Arid Land 2016年第2期8卷 197-206页

作者： WAN Honglian HUANG Chunchang PANG Jiangli Key Laboratory of Disaster Monitoring and Mechanism Simulation of Shaanxi Province Baoji University of Arts and Sciences Department of Geographical Science and Environmental Engineering Baoji University of Arts and Sciences College of Tourism and Environmental Sciences Shaanxi Normal University

Palaeohydmlogical investigations were carried out in the Guchuan Basin in the upper reaches of the Weihe River valley, China. A set of palaeoflood slackwater deposits （SWDs） was found interbedded in the Holocene Ioess-paleosol sequence at the Guchuanzhen site （GCZ）. These palaeoflood SWDs were studied by field observations and laboratory analyses including concentrations of chemical elements and optically stimulated luminescence （OSL） dating. The results showed that the palaeoflood SWDs were the result of the secondary separations of the surface soil and weathered soil layers during the process of water transport and deposition, and without obvious weathering during soil development. These extraordinary flood events were dated back to 3,200-3,000 a B.P. with the OSL method and checked by archaeological dating of the human remains retrieved from the profile. These extraordinary flood events were therefore considered as regional expression of known climatic events and demonstrated the climatic instability in the Holocene. This result is important for understanding the effects of global climate change on the dynamics of river systems.

关键词： upper reaches of the Weihe River Holocene Ioess-paleosol sequence major elements

Selected ions and major and trace elements as contaminants in coal-waste dump water from the Lower and Upper Silesian Coal Basins(Poland)

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International Journal of Coal Science & Technology 2021年第4期8卷 790-814页

作者： Lucyna Lewiriska-Preis Ewa Szram Monika J.Fabianska Adam Nadudvari Magdalena Misz-Kennan Anna Abramowicz Lukasz Kruszewski Andrzej Kita Faculty of Natural Sciences University of Silesia60 Bedzinska St.41-200 SosnowiecPoland Institute of Geological Sciences Polish Academy of Sciences(ING PAN)51/55 Twarda St.00-818 WarsawPoland Faculty of Mathematics Physics and ChemistryUniversity of Silesia9 Szkolna Street40-006 KatowicePoland

Many temporary and permanent reservoirs of water occur on or near coal-waste dumps in the Lower-and Upper Silesian Coal Basins(Poland).Little or nothing is known of the degree to which their water chemistry might reflect(i)reservoir type,i.e.,whether permanent or temporary,(ii)level of coal-waste thermal activity,i.e.,whether inactive or self-heating or burnt-out or(iii)region,i.e.,whether the dumps are in Upper-or Lower *** provide some answers,concentrations of selected ions(NH_(4)^(+),HCO_(3)^(-),F^(-),Cl^(-),Br^(-),NO_(2)^(-),NO_(3)^(-),PO_(4)^(3-),SO_(4)^(2-))were determined by ion chromatography and of nineteen elements(Al,B,Ba,Ca,Cd,Cr,Cu,Fe,K,Li,Mg,Mn,Na,P,Pb,S,Si,Sr,Zn)by inductively coupled plasma mass spectrometry(ICP-MS).The data allow a number of the following *** permanent reservoirs are considered,there is a clear relationship between concentrations of ions and major and trace elements and dump thermal *** highest concentrations occur where the thermal activity is high as inorganic components are transformed into more water-soluble *** dump thermal activity shows a regional pattern,it follows also that elemental and ion concentrations in the dump waters show significant regional *** temporary reservoirs,concentrations of ions and major and trace elements are much lower and any correlations between components less significant than in the permanent reservoirs;these reservoirs exist for too short a time for any balance between coal waste-and water components to be established.

关键词： Coal-waste dump water Self-heating Main ion concentrations major elements Trace elements

Paleoenvironmental Characteristics of Paleogene Lacustrine Source Rocks in the Western Bozhong Sag,Bohai Bay Basin,China:Evidence from Biomarkers,major and Trace elements

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 220-240页

作者： WANG Xiang LIU Guangdi SONG Zezhang SUN Mingliang WANG Xiaolin WANG Feilong CHEN Rongtao GENG Mingyang LI Yishu State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China College of Geosciences China University of PetroleumBeijing 102249China China National Offshore Oil Co. Ltd.(CNOOC)Tianjin Branch CompanyTianjin 300459China CNOOC Research Institute Beijing 100028China

The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain *** address these issues,based on Rock-Eval pyrolysis,kerogen macerals,H/C and O/C ratios,GC-MS,major and trace elements,the Dongying Formation Member(Mbr)3(E_(3)d_(3)),the Shahejie Formation mbrs 1 and 2(E_(2)s_(1+2)),and the Shahejie Mbr 3(E_(2)s_(3))source rocks in the western Bozhong Sag were *** above methods were used to reveal their geochemical properties,OM origins and depositional environments,all of which indicate that E_(2)s_(1+2)and E_(2)s_(3)are excellent source rocks,and that E_(3)d_(3)is of the second good quality.E_(3)d_(3)source rocks were formed under a warm and humid climate,mainly belong to fluvial/delta facies,the E_(3)d_(3)sediments formed under weakly oxidizing and freshwater ***,the depositional environments of E_(2)s_(1+2)source rocks were arid and cold climate,representing saline or freshwater lacustrine facies,and the sediments of E_(2)s_(1+2)belong to anoxic or suboxic settings with large evaporation and *** the period of E_(2)s_(3),the climate became warm and humid,indicating the freshwater lacustrine facies,and E_(2)s_(3)was characterized by freshwater and abundant ***,compared with other intervals,the OM origin of E_(3)d_(3)source rocks has noticeable terrestrial *** OM origin of the E_(2)s_(1+2)and E_(2)s_(3)are mainly plankton and *** subsidence and climate change have affected the changes of the depositional environment in the western Bozhong Sag,thus controlling the distribution of the source rocks,the geochemical characteristics in the three intervals of lacustrine source rocks have distinct ***,these factors are effective to evaluate the paleoenvironmental characteristics of source rocks by biomarkers,major and trace *** established models

关键词： petroleum geology source rocks depositional environments biomarkers major elements trace elements Bozhong Sag

Paleoclimatic evolution indicated by major geochemical elements from aeolian sediments on the east of Qinghai Lake

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Research in Cold and Arid Regions 2013年第3期5卷 301-308页

作者： Yuan Shang RuiJie Lu FeiFei Jia LiHui Tian QingLiang Tang Yuan Chen Chao Zhao WangYang Wu Key Laboratory of Environmental Change and Natural Disaster (Ministry of Education) Beijing Normal University Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

As the largest inland lake of China, along with its unique landscape and geographical location, Qinghai Lake has got much atten- tion of the scientists for a long time. The precursors have done substantive researches by using the lake sediment, which deepen our tmderstanding of the climate changes in this region. Although sand dunes and loess sediment are widely distributed around the lake, so far the researches on geochemical elements from aeolian sediment have been less reported. In this paper, we selected a typical aeolian profile on the east of Qinghai Lake. Based on systematic sampling and analysis of seven major geochemical ele- ments, combined with OSL dating and previous researches, this paper discusses climate changes in the Qinghai Lake area since 12.5 ka B.P.. Our conclusions are：（1） Before 12.5 ka B.P., the climate in this region was dry, cold, and accompanied by strong wind-sand activities. （2） During 12.5-11.9 ka B.P., the climate became warm and wet. However, there was an abrupt climate cooling event during 12.2-11.9 ka B.P., which likely corresponded to the Younger Dryas event. （3） During 11.9 8.0 ka B.P., the climate fluctuated greatly and frequently from warm to cold, and three cooling events occurred. （4） During 8.0-2.6 ka B.P., the climate was warm and humid. （5） Since 2.6 ka B.P., similar to the modem climate, the climate was mainly dry and cold.

关键词： Qinghai Lake OSL dating major elements climate change

Study on the major and Trace elements in Soil of Yunnan Farmland

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Agricultural Science & Technology 2014年第12期15卷 2141-2144页

作者：徐娟刘刚赵兴祥赵帅群任静胡建飞云南师范大学物理与电子信息学院云南昆明650500

In order to investigate the distribution of soil available micronutrients, and provide a theoretical basis for management of fertilizing reasonably on crops, the contents of major and trace elements （P, K, Ca, Mg, Cu, Fe, Zn, and Mn） in farm- land soil collected from Yunnan Province were determined by inductively coupled plasma-mass spectrometry （ICP-MS）, the contents and distribution of major and trace elements were also studied. The results showed that the contents of available P, K were balance, available Ca, Mg were deficient, and available Cu, Fe, Zn, Mn were very plentiful. major and trace elements distribution of different landform areas were obviously different. The contents of trace elements （Fe, Zn and Mn） of central Yunnan Red Plateau were significantly higher than those of Hengduan Mountains in western Yunnan and those of karst plateau in eastern Yunnan. The contents of available P, K, and Ca gradually declined from west to east, while the content of available Cu rose gradually from west to east. The results are reference value to elements determination and agricultural production in farmland soils.

关键词： ICP-MS Soil of Yunnan farmland major elements Trace elements Content

Mantle melting beneath the Southwest Indian Ridge: signals from clinopyroxene in abyssal peridotites

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Acta Oceanologica Sinica 2013年第12期32卷 50-59页

作者： WANG Wei CHU Fengyou ZHU Jihao DONG Yanhui YU Xing CHEN Ling LI Zhenggang The Second Institute of Oceanography State Oceanic Administration

The mineral chemistry and texture of clinopyroxenes in peridotite from the Kingkong tectonic zone of the Southwest Indian Ridge segment in an effort to constrain mantle melting beneath this slow-spreading ridge are reported. There are three types of clinopyroxenes in the abyssal peridotites： coarse-grained, intergranu- lar and exsolved. The compositional variations among these three types suggest that the coarse-grained clinopyroxene is a mantle-derived source. The A1, Na and Ti contents and the Na/Ti ratio of the coarse- grained clinopyroxene may be used to monitor the degree of partial melting, combined with the contradis- tinction with Spinel Cr#, which is calculated to be between 7.9% and 14.9%, and may represent low degrees of melting in the global ocean ridge system. The along-axis compositional variations in the coarse-grained clinopyroxene suggest that the degree of partial melting is primarily controlled by the transform faults on both sides of the ridge. Nonetheless, the northwestern side of the ridge may be affected by a hypothesised detachment fault as documented by the calculated P-T conditions. Simultaneously high Na and low Ti con- tents in the coarse-grained clinoovroxene points to mantle heterogeneities along the ridge axis.

关键词： partial melting abyssal peridotite clinopyroxene major elements SWIR

Reconstruction of the Yangtze Ramp during Floian to Darriwilian(Ordovician)in South China:Its Morphology,Controlling Factors and Significances

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Acta Geologica Sinica(English Edition) 2023年第6期97卷 1756-1777页

作者： LUAN Xiaocong Andre DESROCHERS WU Rongchang LIU Jianbo WANG Guangxu LIANG Yan ZHANG Yuchen WEI Xin LI Lixia ZHAN Renbin State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontologyand Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Department of Geological Science University of SaskatchewanSaskatoonSaskatchewan S7N 5E2Canada Department of Earth and Environmental Sciences University of OttawaOttawaOntario K1N 6N5Canada Paleontology and Stratigraphy School of Earth and Space SciencesPeking UniversityBeijing 100871China University of Chinese Academy of Sciences Beijing 100049China

A robust stratigraphic framework and a coherent depositional ramp model for the Zitai,Dawan,Meitan and Ningkuo formations of Floian–Darriwilian age(Early–Middle Ordovician)in the Yangtze(Daoba,Xiangshuidong,Daling,Gudongkou and Honghuayuan sections)and Jiangnan regions(Nanba section)was created based on lithofacies and major element *** siliciclastic(LF1–3)and six carbonate(LF4–9)lithofacies are recognized representing sediments that were deposited in mixed siliciclastic and carbonate ramp *** intensity of mixed sedimentation and terrigenous input were evaluated using the elemental proxies Intensity of Mixed sedimentation(IM)and Aluminum Accumulation Rate(Al AR),as well as their mean values during certain time *** sediments are most well-developed along the marginal Yangtze region,strongly impacted by recurrent influx of westerly derived terrigenous materials in response to global eustatic changes and regional tectonic movements,shaping the gently southeast-dipping *** terrigenous influx resulted in periods of enhanced primary productivity on the Yangtze Ramp as evidenced by matching biodiversity peaks in planktonic organisms,i.e.,chitinozoans and *** and other shelly fauna were also able to proliferate as new niches developed along the gently dipping ramp floor with substrate *** biodiversification patterns suggest that terrigenous influx controlled in part by regional tectonics played a more important role than previously thought in the development of Great Ordovician Biodiversification Event in South China.

关键词： mixed siliciclastic-carbonate sedimentation ramp Stage Slice lithofacies major elements Great Ordovician Biodiversification Event(GOBE)

Chemical weathering in Malay Peninsula and North Borneo:Clay mineralogy and element geochemistry of river surface sediments

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Science China Earth Sciences 2011年第2期54卷 272-282页

作者： WANG Hao LIU ZhiFei Edlic SATHIAMURTHY Christophe COLIN LI JianRu ZHAO YuLong State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Institute of Oceanography University Malaysia Terengganu Kuala Terengganu 21030 Malaysia Laboratoire IDES Bat. 504 UMR 8148 CNRS Universite de Paris XI Orsay 91405 France

Weathering products of silicate rocks are particularly useful for evaluating the continental chemical weathering on the Earth's surface and its *** mineralogy and major-element geochemistry of surface sediment samples collected in major rivers of Malay Peninsula and North Borneo in the tropical Southeast Asian region are used to study the present chemical weathering process and its controlling factors of tropical *** results indicate that the clay mineral assemblage in Malay Peninsula consists dominantly of kaolinite(average 80%) and minor illite(average 17%),almost without chlorite and smectite,whereas in North Borneo it consists mainly of illite and chlorite,with minor amounts of kaolinite(average 14%) and no *** contents of illite and chlorite in both Northwest and Northeast Borneo are 84% and 87%,***-element geochemical results of both bulk and clay-fraction sediments show intensive chemical weathering degree for both ***,the chemical weathering degree is gradually strengthened from Northeast Borneo,Northwest Borneo,to Malay Peninsula,and it is extremely intensive in Malay *** results indicate that,in the tropical Southeast Asian region exampled by Malay Peninsula and Borneo,climatic condition of tropical warm temperature and East Asian monsoon rainfall is the first-order controlling factor on the chemical weathering,resulting in intensive chemical weathering throughout tropical areas,and tectonic activity and lithology of parent rocks are subordinate factors,which still have an important impact on the weathering products,forming completely different clay mineral assemblages between Malay Peninsula and Borneo.

关键词： clay minerals major elements fluvial sediments chemical weathering Malay Peninsula Borneo

Sedimentary sources and processes in the eastern Arabian Sea:Insights from environmental magnetism,geochemistry and clay mineralogy

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Geoscience Frontiers 2016年第2期7卷 253-264页

作者： Kumar Avinash P.John Kurian Anish Kumar Warrier R.Shankar T.C.Vineesh Rasik Ravindra Earth System Science Organization National Centre for Antarctic and Ocean Research(ESSO-NCAOR)Ministry of Earth Sciences(MoES) Department of Marine Geology Mangalore University Earth System Science Organization Ministry of Earth Sciences(MoES)

The spatial distribution patterns of surficial sediment samples from different sedimentary domains （shallow to deep-sea regions） of the eastern Arabian Sea were studied using sediment proxies viz. environmental magnetism, geochemistry, particle size and clay mineralogy. Higher concentrations of magnetic minerals （high Xlf） were recorded in the deep-water sediments when compared with the shallow water sediments. The magnetic mineralogy of one of the shallow water samples is influenced by the presence of bacterial magnetite as evidenced from the XARM/Xlf VS. XARM/Xfd biplot. However, the other samples are catchment-derived. The high correlation documented for Xlf, anhysteretic remanent mag- netisation （XARM） and isothermal remanent magnetisation （IRM） with Al indicates that the deep-sea surflcial sediments are influenced by terrigenous fluxes which have been probably derived from the southern Indian rivers, the Sindhu （the Indus） and the Narmada-Tapti rivers. A lower Mn concentration is recorded in the upper slope sediments from the oxygen minimum zone （OMZ） but a higher Mn/AI ratio is documented in the lower slope and deep-sea sediments. Clay minerals such as illite （24-48.5%）, chlorite （14.1-34.9%）, smectite （10.6-28.7%） and kaolinite （11.9-27.5%） dominate the sediments of shallow and deep-sea regions and may have been derived from different sources and transported by fluvial and aeolian agents. Organic carbon （OC） data indicate a low concentration in the shallow/shelf region （well oxygenated water conditions） and deeper basins （increased bottom-water oxygen concentration and low sedimentation rate）. High OC concentrations were documented in the OMZ （very low bottom-water oxygen concentration with high sedimentation rate）. The calcium carbonate concentration of the surface sediments from the continental shelf and slope regions （〈 1800 m） up to the Chagos-Laccadive Ridge show higher concentrations （average - 58%） when compared to deep basin sediments （average - 44%）.

关键词： Magnetic minerals major elements Organic carbon Calcium carbonate Terrigenous fluxes Eastern Arabian Sea