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Five Years of IGCP 649 Project-Diamonds and Recycled Mantle

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Acta Geologica Sinica(English Edition) 2020年第S1期94卷 1-3页

作者： YANG Jingsui SHEN Tingting ZHANG Cong QIU Tian key laboratory of deep-earth dynamics of ministry of natural resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China School of earth Sciences and Engineering Nanjing UniversityNanjing 210023China

The IGCP-649 project―Diamonds and Recycled Mantle‖is an International Geosciences Program sponsored by UNESCO and IUGS in March *** is a global research project,aimed to carry out extensive and systematic research on peridotites,chromitites and related materials such as diamond,moissanite and other unusual minerals,from different ophiolites in global orogenic belts,for understanding the formation and origin of deepmantle minerals in oceanic lithosphere,the origin of carbon for the ophiolite-hosted diamonds,the evolution of earth’s mantle and the dynamic process of ophiolite *** IGCP-649 project(2015–2019)is undertaken by the Center for Advanced Research on the Mantle(CARMA),leading by *** Yang,Institute of Geology,Chinese Academy of Geological Sciences,and cooperated by an international team of researchers including *** Dilek of Miami University(USA),*** L Griffin of Macquarie University(Australia),*** *** of Dalhousie University(Canada),*** Milushi of Polytechnic University of Tirana(Albania),and *** Metwaly Abu Anbar of Tanta University(Egypt).

关键词： IGCP mantle minerals

Petrogenesis and Tectonic Implications of the Paiku Leucogranites,Northern Himalaya

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Journal of earth Science 2019年第3期30卷 525-534页

作者： Zhengbin Gou Xin Dong Baodi Wang Chengdu Center China Geological SurveyChengdu 610081 China key laboratory of deep-earth dynamics of ministry of natural resources Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

The Himalayan leucogranites provide insights into the partial melting behavior of relatively deeper crustal rocks and tectono-magmatic history of the Himalayan Orogen. The Paiku leucogranites of northern Himalaya can be subdivided into two-mica leucogranite(TML), garnet-bearing leucogranite(GL), cordierite-bearing leucogranite(CL), and tourmaline-bearing leucogranite(TL). All of them are high-K, peraluminous, calc-alkalic to alkali-calcic rocks. They are enriched in light rare earth elements(LREE) and large ion lithophile elements(LILE), and show pronounced negative anomalies of Sr, Ba, K and Ti, but positive anomalies of Nb and Rb. LA-ICP-MS U-Pb zircon dating of one TML, one GL, and two CL samples yielded variable 206Pb/238U ages ranging from 23.6 to 16.1 Ma, indicating the Paiku leucogranites underwent a low degree of partial melting process. Combining with previous studies, we suggest the Paiku leucogranites were derived from partial melting of metasedimentary rocks of the Higher Himalayan Sequence(HHS). The GL and TL mainly resulted from the muscovite-dehydration melting, whereas the TML and CL were mainly derived from the biotite-dehydration melting. Finally, it is concluded that the Paiku leucogranites were probably formed during the subduction of the Indian crust.

关键词： Paiku leucogranites petrochemistry U-Pb geochronology dehydration melting tectonic implications northern Himalaya

The optical and molecular signatures of DOM under the eutrophication status in a shallow,semi-enclosed coastal bay in southeast China

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Science China earth Sciences 2021年第7期64卷 1090-1104页

作者： Chen ZHAO Yuping ZHOU Yu PANG Yanzhen ZHANG Wei HUANG Yuntao WANG Ding HE key laboratory of Geoscience Big Data and deep Resource of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhou 310027China State key laboratory of Satellite Ocean Environment dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310027China

We applied stable carbon isotopes,ultraviolet-visible absorption(UV-Vis),fluorescence excitation-emission matrices spectroscopy(EEMs),and Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS)to investigate the chemical composition and sources of the dissolved organic matter(DOM)in both the water column and pore water in Xiangshan Bay,a representative semi-enclosed and eutrophic bay in Zhejiang Province,*** protein-like fluorescent component(C1)and two humic-like fluorescent components(C2 and C3)were identified by PARAFAC *** concentration of dissolved organic carbon(DOC),the relative intensities of C2,C3,and black carbon-like compounds are all negatively correlated with salinity,indicating that there is a dilution effect of terrestrial signals by seawater in Xiangshan *** differences in light penetration ability of Xiangshan Bay cause different degrees of photo-degradation,which may play an important role in the transformation of organic matter in Xiangshan *** weak correlation between the C1 fluorescent component and salinity indicates that autochthonous sources cannot dominate the protein-like FDOM in the Xiangshan Bay drainage *** sources(such as anthropogenic inputs and release of pore water)also affect the distribution of the protein-like fluorescent component under eutrophication *** relative proportion of the protein-like fluorescent component in Xiangshan Bay is on a medium level in China and anthropogenic inputs may be a significant source of DOM in coastal bays.

关键词： Xiangshan Bay Dissolved organic matter Optical properties Molecular composition Transporting and processing

Tidal variation of total suspended solids over the Yangtze Bank based on the geostationary ocean color imager

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Science China earth Sciences 2020年第9期63卷 1381-1389页

作者： Yu ZHOU Jiliang XUAN Daji HUANG State key laboratory of Satellite Ocean Environment dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China key laboratory of Conservation and Restoration of Tropical and Subtropical Marine natural resources Fourth Institute of OceanographyMinistry of Natural ResourcesBeihai 536000China

Hourly mapping by a Geostationary Ocean Color Imager was used to reveal the spatial pattern and tidal variation of total suspended solids(TSS)over the Yangtze Bank in the Yellow and East China Seas during the *** TSS form a tongueshaped structure,which decreases further offshore in a stepwise *** stepwise change is separated by two fronts of TSS,which are located near the 20-m and 50-m *** tidal variation of TSS concentration during the study period is evident and can be divided into three stages:decay,maintenance,and *** with the relatively stationary TSS during the maintenance stage,drastic changes exist during the decay and growth *** terms of tide-induced mixing,the dynamic analysis shows that both the topography and the tidal currents play an important role in the spatio-temporal variation of TSS during the tidal *** particular,spatial distribution is primarily determined by the topography,whereas the temporal variations in tidal scale are determined by the tidal currents.

关键词： Yangtze Bank Total suspended solid(TSS) Particle concentration Tidal variation Tide-induced mixing

Tracing nitrate sources in one of the world's largest eutrophicated bays(Hangzhou Bay):insights from nitrogen and oxygen isotopes

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Acta Oceanologica Sinica 2024年第6期43卷 86-95页

作者： Zhi Yang Jianfang Chen Haiyan Jin Hongliang Li Zhongqiang Ji Yangjie Li Bin Wang Zhenyi Cao Qianna Chen key laboratory of Marine Ecosystem dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China State key laboratory of Satellite Ocean Environment dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

Eutrophication caused by inputs of excess nitrogen(N) has become a serious environmental problem in Hangzhou Bay(China),but the sources of this nitrogen are not well *** this study,the August 2019 distributions of salinity,nutrients [nitrate(NO_(3)^(-)),nitrite,ammonium,and phosphate],and the stable isotopic composition of NO_(3)^(-)(δ^(15)N and δ^(18)O) were used to investigate sources of dissolved inorganic nitrogen(DIN) to Hangzhou B *** distributions of nitrate,salinity,and nitrate δ^(18)O indicate that the Qiantang River,the Changjiang River,and nearshore coastal waters may all contribute nitrate to the *** on the isotopic compositions of nitrate in these potential source waters and conservative mixing of nitrate in our study area,we suggest that the NO_(3)^(- )in Hangzhou B ay was likely derived mainly from soils,synthetic N fertilizer,and manure and ***-member modeling indicates that in the upper half of the bay,the Qiantang River was a very important DIN source,possibly contributing more than 50% of DIN in the bay head *** the lower half of the bay,DIN was sourced mainly from strongly intruding coastal *** coming directly from the Changjiang River made a relatively small contribution to Hangzhou Bay DIN in August 2019.

关键词： nitrogen isotopes oxygen isotopes nitrogen cycle nitrate sources Hangzhou Bay

Palynological constraints on the age of the Mississippi Valley-type Changdong Pb-Zn deposit,Sanjiang belt,West China

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Science China earth Sciences 2022年第1期65卷 167-181页

作者： Yingchao LIU Yucai SONG Zengqian HOU Dangpeng XI Suping LI Longlong YUE Wang MA Bolang TANG key laboratory of deep-earth dynamics of ministry of natural resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China School of earth Science and resources China University of Geosciences(Beijing)Beijing 100083China Jiangsu Nanjing Institute of Geo-Engineering Investigation Nanjing 210041China

Mississippi Valley-type(MVT)Pb-Zn deposits serve as the world’s major supply of Pb-Zn ***,the age constraint of MVT Pb-Zn deposits has long been a big challenge,due to the lack of minerals that are unequivocally related to ore deposition and that can be used for radioisotopic *** we show sporopollens can provide useful chronological information on the Changdong MVT Pb-Zn deposit in the Simao basin,Sanjiang belt,West *** Pb-Zn ores in the Changdong deposit are hosted by internal sediments in paleo-karst caves of meteoric *** and galena occur as replacements of carbonate minerals and void infillings in the internal *** relations suggest that the Pb-Zn mineralization occurred after the deposition of the internal sediments.A palynological assemblage mainly composed of angiosperm pollen dominated by Castanea,Quercus,and Carya and fern spores dominated by Polypodiaceae,Pteris,and Athyriaceae was *** pollen and spores place the ore-hosting internal sediments and the Changdong paleo-karst at early to middle ***,the Changdong Pb-Zn deposit must have formed after the early Oligocene(~34 Ma).These age constraints,together with the geological characteristics,indicate that the Changdong Pb-Zn deposit is a paleo-karst-controlled MVT deposit related to fold-thrust systems in the Sanjiang *** Changdong deposit is similar to other MVT Pb-Zn deposits in the northern part of the Sanjiang belt,making it possible to extend this Pb-Zn belt 500 km further to the *** presented here highlights the potential of sporopollens in dating the age of MVT deposits related to paleo-karst formation in young orogenic belts.

关键词： Mississippi Valley-type(MVT)Pb-Zn deposits Age constraint Palynomorphs Internal sediments Paleo-karst Changdong deposit Sanjiang fold-thrust belt

Lateral downslope transport and tentative sedimentary organic carbon box model in the southern Yap Trench,western Pacific Ocean

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Acta Oceanologica Sinica 2023年第1期42卷 61-74页

作者： Dong Li Jun Zhao Chenggang Liu Jianming Pan Ji Hu key laboratory of Marine Ecosystem dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou310012China

Sediment collapse and subsequent lateral downslope migration play important roles in shaping the habitats and regulating sedimentary organic carbon(SOC)cycling in hadal *** this study,three sediment cores were collected using a human-occupied vehicle across the axis of the southern Yap Trench(SYT).The total organic carbon(TOC)and total nitrogen(TN)contents,δ13C,radiocarbon ages,specific surface areas,and grain size compositions of sediments from three cores were *** explored the influence of the lateral downslope transport on the dispersal of the sediments and established a tentative box model for the SOC *** the SYT,the surface TOC content decreased with water depth and was decoupled by the funneling effect of the V-shaped hadal ***,the sedimentation(0.0025 cm/a)and SOC accumulation rates(∼0.038 g/(m^(2)·a)(in terms of OC))were approximately 50%higher in the deeper hadal region than in the abyssal region(0.0016 cm/a and∼0.026 g/(m^(2)·a)(in terms of OC),respectively),indicating the occurrence of lateral downslope *** fluctuating variations in the prokaryotic abundances and the SOC accumulation rate suggest the periodic input of surficial sediments from the shallow *** similar average TOC(0.31%–0.38%),TN(0.06%–0.07%)contents,and SOC compositions(terrestrial OC(11%–18%),marine phytoplanktonic OC(45%–53%),and microbial OC(32%–44%))of the three sites indicate that the lateral downslope transport has a significant mixing effect on the SOC *** output fluxes of the laterally transported SOC(0.44–0.56 g/(m^(2)·a)(in terms of OC))contributed approximately(47%–73%)of the total SOC input,and this proportion increased with water *** results of this study demonstrate the importance of lateral downslope transport in the spatial distribution and development of biomes.

关键词： southern Yap Trench sedimentary organic carbon cycling lateral downslope transport diluting effect box model

Environmental drivers of phytoplankton crops and taxonomic composition in northeastern Antarctic Peninsula adjacent sea area

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Acta Oceanologica Sinica 2022年第1期41卷 99-117页

作者： Yubin Feng Dong Li Jun Zhao Zhengbing Han Jianming Pan Gaojing Fan Haisheng Zhang Ji Hu Haifeng Zhang Jiaqi Wu Qiuhong Zhu key laboratory of Marine Ecosystem dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

The ecosystem of the sea region adjacent to the Antarctic Peninsula is undergoing remarkable physical and biological changes, in the context of global warming. However, understanding of the dynamics of phytoplankton taxonomic composition in this marginal ice zone remains unclear. In this study, seawater samples collected from 36 stations in the northeastern Antarctic Peninsula were analyzed for nutrients and phytoplankton *** with CHEMTAX analysis, remote sensing data, and physicochemical measurements, we investigated the relationships between phytoplankton crops, taxonomic composition, and marine environmental *** chlorophyll a(Chl a) concentrations(200 m) varied from 8.9 mg/m^(2)to 64.2 mg/m^(2), with an average of(23.2±12.0) mg/m^(2)and higher phytoplankton biomass concentrated in the coastal region of South Orkney Island and South Shetland Island. Diatoms were the dominant functional group(63%±21%). Higher proportions of diatoms were associated with higher Chl a(r=0.40, pdeeper mixed layer depths(r=0.17, p0.35, p<0.01), and lower MWC(r=-0.20, p<0.01). In comparison, the total contribution from green flagellates(4%±5%), cryptophyta(1%±3%), dinoflagellates(1%±4%), and cyanobacteria(1% ± 5%) was only 6%. In offshore regions with well-mixed water, less varied taxonomic composition and lower crops with a higher proportion of nanophytoplankton were observed. In contrast, significantly decreasing crops below the mixed layer depth was observed in

关键词： Antarctic Peninsula phytoplankton crops phytoplankton taxonomic composition pigment light intensity mixed layer depth

Neoproterozoic–Early Paleozoic Tectonic Evolution of the South China Craton： New Insights from the Polyphase Deformation in the Southwestern Jiangnan Orogen

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Acta Geologica Sinica(English Edition) 2018年第5期92卷 1700-1727页

作者： ZHAO Zhongbao XU Zhiqin MA Xuxuan LIANG Fenghua GUO Peng key laboratory of deep-earth dynamics of ministry of natural resources China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China State key laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210046 China School of earth Science and resources China University of Geosciences Beijing 100083 China

A 〉1500–km–long northeast–southwest trending Neoproterozoic metamorphic belt in the South China Craton（SCC） consists of subduction mélange and extensional basin deposits. This belt is present under an unconformity of Devonian–Carboniferous sediments. Tectonic evolution of the Neoproterozoic rocks is crucial to determining the geology of the SCC and further influences the reconstruction of the Rodinia supercontinent. A subduction mélange unit enclosed ca.1000–850–Ma mafic blocks, which defined a Neoproterozoic ocean that existed within the SCC, is exposed at the bottom of the Jiangnan Orogen（JO） and experienced at least two phases deformation. Combined with new（detrital） zircon U–Pb ages from metasandstones, as well as igneous rocks within the metamorphic belt, we restrict the strongly deformed subduction mélange as younger than the minimum detrital age ca. 835 Ma and older than the ca. 815 Ma intruded granite. Unconformably overlying the subduction mélange and the intruded granite, an intra–continental rift basin developed 〈800 Ma that involved abundant mantle inputs, such as mafic dikes. This stratum only experienced one main phase deformation. According to our white mica ^40Ar/^（30）Ar data and previously documented thermochronology, both the Neoproterozoic mélange and younger strata were exhumed by a 490–400–Ma crustal–scale positive flower structure. This orogenic event probably induced the thick–skinned structures and was accompanied by crustal thickening, metamorphism and magmatism and led to the closure of the pre–existing rift basin. Integrating previously published data and our new results, we agree that the SCC was located on the periphery of the Rodinia supercontinent from the Neoproterozic until the Ordovician. Furthermore, we prefer that the convergence and dispersal of the SCC were primarily controlled by oceanic subduction forces that occurred within or periphery of the SCC.

关键词： Rodinia supercontinent South China Craton Jiangnan Orogen intra–continental rifting intra–continental orogen