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Journal of Rare Earths 2012年第11期30卷 1184-1190页

作者：徐兆凯李铁刚常凤鸣 CHOI Jinyong LIM Dhongil 徐方建 Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of Sciences Department of Oceanography Kunsan National University South Sea Institute Korea Ocean Research and Development Institute School of Geo-sciences China University of Petroleum

Rare earth elements （REE） compositions and discriminant function were successfully used to examine high resolution sediment source changes in the northern Okinawa Trough over the last 24.1 ka, especially for the influence from the Yellow River and the Tsushima Warm Current （TWC） that has not been well solved. Variations of these parameters were clearly divided into three distinct depositional units. During Interval 1 （24.1-16.0 ka BP）, the paleo-Yellow River and the paleo-Yangtze River mouths were situated near the studied area and could have played major roles in the sedimentation therein. In Interval 2 （16.0-7.3 ka BP）, these river mouths gradually retreated with global sea-level rise, leading to less fluvial inputs from them to the northern Okinawa Trough. Meanwhile, formation of the TWC could carry some sediment loads of Taiwan to the studied core, especially during its late phase （8.0-7.3 ka BP）. Modem oceanographic conditions, with a predominance of the TWC, were finally established since the beginning of Interval 3, causing more ten＇igenous contribution from Taiwan to the studied area. Subsequently, modem depositional environments mainly influenced by the Yellow River, the Yangtze River, and the TWC were finally formed.

关键词： sediment provenance discriminant function rare earth elements Tsushima Warm Current northern Okinawa Trough

Thrusting and Exhumation Processes of a Bounding Mountain Belt: Constraints from sediment provenance Analysis of the Hefei Basin

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Acta Geologica Sinica(English Edition) 2001年第2期75卷 144-150页

作者：刘少峰刘文灿戴少武黄思骥陆五云 Faculty of Geosciences and Resources China University of Geosciences Institute of Exploration and Development Jianghan Petroleum Administration China University of Geosciences Anhui Bureau of Geology and Mineral Resources

Lithic (or gravel) composition analyses of the Jurassic Sanjianpu Formation and Fenghuangtai Formation in the Hefei basin show that the sediment provenance consists mainly of four kinds of rock units: the basement metamorphic complex, granitic rocks, medium- and low-grade metamorphic rocks, and sandy and muddy sedimentary rocks, which are distributed along the bounding thrust belt. The whole stratigraphic section can be divided into 2 lithic sequences and 7 subsequences. The regular distribution and changes of lithic fragments and gravels in lithic (or gravel) sequences reflect that the bounding thrust belt of basin has undergone 2 thrusting cycles and 7 thrusting events. Lithic (or gravel) composition analyses of the basin fully reveal that the northern Dabie basement metamorphic complex was exhumed on the earth's surface in the Middle and Late Jurassic, and extensive intermediate and acid intrusive rocks were developed in the southern North Huaiyang or northern Dabie Mountains during the basin's syndepositional stage.

关键词： northern Dabie Mountains Hefei basin sediment provenance thrusting and exhumation

Evolution of Asian drying since 30 Ma revealed by clay minerals record in the West Pacific and its tectonic-climatic forcing

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Science China Earth Sciences 2023年第6期66卷 1365-1382页

作者： Yi TANG Shiming WAN Debo ZHAO Zhaojie YU Zhaokai XU Jin ZHANG Zehua SONG Mengjun LI Hualong JIN Wenjun JIAO Hongkun DONG Anchun LI Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China University of Chinese Academy of Sciences Beijing 100049China

As the second largest dust source on the globe,the tectonic and climatic evolution of continental Asia has an important impact on regional and global climate change.The West Pacific is the main sediment sink for eolian dust transported eastward from the Asian interior.Clay minerals,as the major fine-grained weathering products of continental rocks,can be readily transported by wind or currents over long distances and thus have been widely used in the reconstruction of paleoclimate and weathering history.However,the overall evolutionary tendency and response mechanism of clay mineral records over large spatial and long timescales across Asia remain unclear.Here,two continuous and high-resolution clay mineral records since 30 Ma were reconstructed from sediments at Deep Sea Drilling Program(DSDP)Sites 292 and 296 in the Philippine Sea.Clay minerals and Sr-Nd isotope compositions were used to constrain provenance and reconstruct the drying history of the dust source region since the Oligocene.The results show that the clay-sized detrital sediments in the Philippine Sea are a mixture of Asian eolian dust and volcanic materials from the West Pacific arcs.Based on the clay mineral compositions and eolian flux,we reveal that the Asian interior has been continuously drying since the late Oligocene and that stepwise enhanced aridification occurred at approximately 20,14,7,and 3 Ma.Compared with other regions of the world,the relative contents of illite and chlorite increased more dramatically in Asia during the late Cenozoic,and the inconsistency became more obvious at approximately 20 Ma.Since 3 Ma,illite and chlorite have increased consistently across the globe.Combined with the Asian tectonic and climatic history,we suggest that the increase in illite and chlorite from Asia between 20 and 3 Ma was mainly in response to the uplift of the Himalayan-Tibetan Plateau,whereas after 3 Ma,it was primarily controlled by global cooling driven by the expansion of the Arctic ice sheet.

关键词： Clay minerals Sr-Nd isotopes sediment provenance Eolian dust West Pacific Late Cenozoic

One size does not fit all: Refining zircon provenance interpretations via integrated grain shape, geochronology, and Hf isotope analysis

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Geoscience Frontiers 2023年第4期14卷 230-244页

作者： Gisela Gartmair Milo Barham Christopher L.Kirkland Timescales of Mineral Systems Group School of Earth and Planetary SciencesCurtin UniversityGPO Box U1987PerthWA 6845Australia

sediment provenance studies commonly utilize isotopic signatures to resolve detrital mineral sources and routing.However,non-unique ages and geochemical characteristics across geographically distinct crystalline source regions can lead to significant ambiguities in mineral provenance interpretations.Such ambiguity is apparent in southern Australia’s Cenozoic Eucla Basin,which hosts world-class heavy mineral sand resources.Here,new Hf isotope data are provided from four heavy mineral prospects(N=8,n=844[N=samples,n=grains]).Zircon grain shape data are also presented for a suite of detrital Eucla Basin samples(N=22,n=35,604)and the basin’s underlying basement,the Coompana Province(N=13,n=824).The data are integrated with published detrital and non-detrital primary zircon data to investigate the efficacy of grain shape analysis to better resolve the basin’s mineral provenance.Zircon Hf isotope compositions indicate a primary Mesoproterozoic juvenile source for zircon melts(~1250-1000 Ma,-2.5~+5)with additional contributions from a range of juvenile to evolved late Archean to Phanerozoic-aged zircon bearing magmas(-28.0+11).U-Pb geochronology and Hf isotopes are incapable of differentiating Mesoproterozoic-aged source rocks bounding the region for the majority of heavy mineral deposits analyzed as potential sources express overlapping crystallization ages and similarities in Hf-isotope characteristics.However,distinct zircon grain shapes(i.e.,perimeter,major axis and circularity)facilitate improved differentiation across these Mesoproterozoic sources.Filtering of U-Pb age,Hf isotope and shape data implicate the underlying Madura and Coompana provinces as dominant sediment sources for Eucla Basin detritus aged~1400-1000 Ma.The lack of direct sediment pathways between the underlying basement provinces and placer sediments analyzed demonstrates the significance of zircon reworking from intermediate sedimentary basins in the formation of the economically significant Eucla Basin beach placers.Zircon grain shape

关键词： Isotope fingerprinting Grain shape analysis sediment provenance sediment routing Heavy mineral sands Eucla Basin

Composition, Source and Environmental Indication of Clay Minerals in sediments from Mud Deposits in he Southern Weihai Offshore, Northwestern Shelf of the South Yellow Sea, China

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Journal of Ocean University of China 2022年第5期21卷 1161-1173页

作者： LIU Jinqing LIU Yilin YIN Ping GAO Fei CAO Ke CHEN Xiaoying College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China

Studying the sedimentary characteristics of the muddy area along the Yellow Sea shelf is of great significance for deep-ening the understanding of the climate and environment evolution since the last glacial period.Recently,a small muddy area developed in the southern Weihai offshore has attracted a lot of attention.Based on high-resolution grain size,clay mineral,AMS14C,and OSL data of sediments from the core WHZK01 in the muddy area,we acquired a new understanding of sedimentary characteristics,sources and paleoclimatic environment during the last 13 kyr.The results show that the core WHZK01 sediments were mainly from the Yellow River and local rivers along the coast.However,the sources varied for different deposition units.The riverbed(before 13 kyr BP)and fluvial plain deposits(13-10 kyr BP)were mainly from local river inputs.The very thin littoral deposits from 10 kyr BP to 8 kyr BP also mainly originate from coastal river inputs,while the littoral-neritic deposits since 8 kyr BP were dominated by the Yellow River materials and partly supplied by the coastal rivers and the island erosion.In addition,five events related with the strong East Asian winter monsoon(EAWM)during the intervals of 13.0-11.0 kyr BP,10.0-8.2 kyr BP,7.0-5.0 kyr BP,3.5-2.5 kyr BP,and 1.2-0.5 kyr BP were iden-tified.Three events related with the enhancement of the EAWM since the middle Holocene have strengthened the transport capacity of the coastal currents of the Shandong Peninsula.Meanwhile,more Yellow River-derived distal sediments were deposited to the southern Weihai offshore and formed wedge-shaped muddy bodies.In short,the ratio of smectite/illite could be used as an effective EAWM indicator since 13 kyr BP on the northwestern shelf of the South Yellow Sea.

关键词： clay minerals sediment provenance East Asian winter monsoon mud deposits southern Weihai offshore South Yellow Sea

Historical variations in autochthonous and allochthonous sediment supplies to the largest freshwater lake in Central India

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International Journal of sediment Research 2022年第5期37卷 563-575页

作者： Nafees Ahmad Satinder Pal Singh Aasif Mohmad Lone Abul Qasim Ravi Bhushan Gyana Ranjan Tripathy Chinmay Shah Department of Earth and Environmental Sciences Indian Institute of Science Education and Research Bhopal Geosciences Division Physical Research Laboratory Department of Earth and Climate Science Indian Institute of Science Education and Research

Lacustrine sediment preserves high-resolution biogeochemical records of past variations in watershed processes controlling lake sedimentation. The current study explores historical variations in autochthonous and allochthonous sediment supplies to a large tropical freshwater lake system(Upper Lake, Bhopal) protected under the international Ramsar Convention of 2002 against anthropogenic pressures. For this purpose, multi-proxy biogeochemical data are presented for organic matter(total organic carbon, total nitrogen, phosphorous, and loss on ignition [LOI] at550°C), carbonate(LOI at 950°C), lithic sediment(aluminum, titanium, iron, calcium, magnesium,sodium, potassium, manganese, zirconium, niobium, hafnium, tantalum, thorium, uranium, and rare earth elements), and anthropogenic inputs(lead) measured in a 38 cm long sediment core retrieved from the lake. In addition to the lacustrine sediment core, the samples of catchment bedrock, surface soils, major stream sediment, and eolian dust collected from the lake periphery also are analyzed. The systematic biogeochemical excursions in the upper core section(top ～8 cm) indicate increased anthropogenic inputs, watershed denudation by agricultural activities, artificially reduced fluvial sediment supply, relatively increased dust inputs and lake eutrophication in the last few decades. The current study underscores the roles of anthropogenic land-use and wetland conservation practices in the rapid alteration of autochthonous and allochthonous sediment supplies to open aquatic ecosystems. Further, rising lake eutrophication levels despite a managed reduction in allochthonous sediment supplies seem challenging to control due to dissolved nutrient supply from urban sewage discharge and runoff from agricultural land in the watershed.

关键词： Upper Lake sediment Geochemistry sediment provenance Eutrophication Anthropogenic inputs

Using a fluvial archive to place extreme flood sediment(dis)connectivity dynamics in context of a longer-term record

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International Journal of sediment Research 2022年第4期37卷 447-456页

作者： Kirstie Fryirs Chris Thompson Damian Gore School of Natural Sciences Macquarie University Seqwater

The aim of this study was to establish the source and provenance of sediments deposited in a large floodplain sink during extreme floods in the Lockyer Creek catchment, Australia, in 2011 and 2013. We place the sediment source patterns in context of the longer-term record to determine whether coarsegrained sediment sources(i.e., very fine sand to very coarse sand) and the spatio-temporal pattern of(dis)connectivity have changed over time. We do this by matching the geochemical properties and age structure of a sediment profile located in a downstream floodplain sink to the elemental composition of source sediments. One hundred and fifty-seven sediment samples from 20 sites across the catchment are analysed using X-ray fluorescence(XRF) spectrometry to compare the elemental ratio composition of the downstream floodplain sink to its source materials. We use Optically Stimulated Luminescence(OSL)dating to determine the age structure of the sediments in the floodplain sink. The northern tributaries and parts of the Lockyer River trunk stream are the primary sources of coarse sediment. These areas are connected(coupled) to the lower trunk stream and floodplain sediment sink. Southern tributaries are largely disconnected(decoupled) and supply little sediment to the floodplain sediment sink. This pattern of sediment source contribution has remained similar over the last 6.8 ka at least. sediment sources as observed in the 2011 flood have predominated over the mid-late Holocene whilst those in the 2013 flood are rare.

关键词： sediment provenance Geomorphology sediment source sediment sink Lockyer Valley

Rare earth element geochemistry in the inner shelf of the East China Sea and its implication to sediment provenances

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Journal of Rare Earths 2011年第7期29卷 702-709页

作者：徐方建李安春李铁刚胥可辉陈世悦邱隆伟操应长 Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences School of Geosciences China University of Petroleum Key Laboratory of Shandong Province for Reservoir Geology China University of Petroleum Department of Marine Science Coastal Carolina University

Gravity core EC2005, located in the mud wedge off the Zhejiang-Fujian coast in the inner shelf of the East China Sea （ECS）, was analyzed for its lithology, grain size, rare earth elements （REE） and AMS14C dating. Results revealed high-resolution paleoenvironmental evolution and multiple switches of sediment provenances in the inner shelf of ECS. The lithology, grain size and REE concentrations of sediments varied significantly down the core. Mean grain size ranged from 8 to 121 μm, and the values of ΣREE were 152.8-227.9 μg/g. The chondrite- and shale-normalized REE patterns indicated their similarity to the terrigenous sediments in the study area. Between 17.3-12.3 ka BP the sediments in the inner shelf of ECS were mainly originated from local drainage basins. The source then gradually switched to the Yangtze River between 12.3 and 9.8 ka BP. Since about 10-9.8 ka BP, the sediments in the study area were dominantly derived from the Yangtze River. The continuous rising of sea level and formation of coastal current along the inner shelf played a key role in the switches of sediment provenances.

关键词： last deglaciation inner shelf of the East China Sea grain size sediment provenance rare earth elements

Composition, origin and weathering process of surface sediment in Kumtagh Desert, Northwest China

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Journal of Geographical Sciences 2011年第6期21卷 1062-1076页

作者： XU Zhiwei LU Huayu ZHAO Cunfa WANG Xianyan SU Zhizhu WANG Zhenting LIU Hongyi WANG Lixin LU Qi School of Geographic and Oceanographic Sciences the MOE Key Laboratory of Coast and Island Development Nanjing University Nanjing 210093 China Institute of Desertification Studies Chinese Academy of Forestry Beijing 100091 China College of Earth and Environmental Sciences Lanzllou University Lanzhou 730000 China Lanzhou Institute of Arid Meteorology China Meteorological Administration Lanzhou 730020 China

Kumtagh Desert is one of the eight biggest deserts in China, but poorly investigated before our interdisciplinary study because of the difficulty of access. In this paper, 33 representative surface sediment samples were collected from the Kumtagh Desert and analyzed in the laboratory to obtain heavy mineral components and geochemical element contents. Results show that various kinds of heavy minerals are present in these samples, with high levels of epidote and hornblende. Si and AI take up a large part of chemical composition. Compared with the average composition of geochemical elements of the upper continental crust （UCC）, except Si and Ca, all elements are depleted to a certain degree; Fe, Mg, Ca, P, Ti and Mn have high correlation coefficients in their contents. The mineral and geochemical composition of the Kumtagh Desert sediments have a similarity with that of rocks of Altyn Tagh Mountains, and the surface sediments of the alluvial/diluvial fans around the Altyn Tagh Mountains and that of the Taklamakan Desert, indicating that one major source of the Kumtagh Desert sediments is located in the Altyn Tagh Mountains. Alluvial deposits and lake sediments in Aqik valley and lower reaches of Shule River are prone to be eroded and transported by the strong northeasterly wind into the Kumtagh Desert, forming another source of the desert deposits. An A-CN-K ternary diagram shows that a weak degree chemical weathering by the loss of Na and K occurred in these sediments, whereas A-CNK-FM ternary diagram suggests that Fe and Mg have undergone a significant chemical differentiation. Physical weathering processes cause easy erosion and enrichment in fine particles for mafic minerals, thus coarse desert sand particles can be relatively depleted in Fe and Mg. The mineral and geochemical composition of sediments in arid regions experiencing less chemical weathering are mostly affected by physical weathering.

关键词： minerals geochemical elements sediment provenance weathering process Kumtagh Desert

A preliminary reassessment of δEu_N-ΣREEs plot for distinguishing sediment provenances

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Journal of Rare Earths 2012年第1期30卷 94-96页

作者：徐方建陈世悦邱隆伟操应长 School of Geosciences China University of PetroleumQingdao 266555China Key Laboratory of Shandong Province for Reservoir Geology China University of PetroleumDongying 257061China

Several REE data sets were collected in Core DD2 and EC2005 in the inner shelf of East China Sea,Core Y127 in the northern Okinawa Trough,Core NT1,C9247 and C92169 in the south Yellow Sea to check the applicability of the δEuN-ΣREEs model for quantita-tively distinguishing sediments from the Yangtze River and the Yellow River.By comparison,several sediments in cores DD2,EC2005,Y127 are generally in accordance with this model.The cores NT1,C9247 and C92169,which have been influenced by the Yangtze River and the Yellow River together,however,were inconsistent with the δEuN-ΣREEs model.The δEuN-ΣREEs plot and its corresponding regression equation,which could be used to distinguish sediments ＂intuitively and quantitatively＂ from the Yangtze River,and the Yellow River should be reconsidered or reassessed.

关键词： rare earths sediment provenance Yangtze River Yellow River