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Acta Oceanologica Sinica 2020年第7期39卷 42-49页

作者： Jie Li Jihao zhu Fengyou Chu Xiaohu Li zhimin zhu Hao Wang Key Laboratory of Submarine Geosciences Ministry of Natural ResourcesHangzhou 310012China Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China

Electron microprobe analysis was conducted on plagioclase from the plagioclase ultraphyric basalts(PUBs)erupted on the Southwest Indian Ridge(SWIR)(51°E)to investigate the geochemical changes in order to better understand the magmatic processes occurring under ultraslow spreading ridges and to provide insights into the thermal and dynamic regimes of the magmatic reservoirs and conduit *** phenocryst cores are generally calcic(An74–82)and are depleted in FeO and *** the phenocryst rims(An67–71)and the plagioclase in the groundmass(An58–63)are more sodic and have higher FeO and MgO contents than the phenocryst *** crystallization temperatures of the phenocryst cores and the calculation of the equilibrium between the phenocrysts and the matrix suggest that the plagioclase cores are unlikely to have crystallized from the host basaltic melt,but are likely to have crystallized from a more calcic *** enrichment in incompatible elements(FeO and MgO),as well as the higher FeO/MgO ratios of the outermost phenocryst rims and the groundmass,are the result of plagioclase-melt disequilibrium diffusion during the short residence time in which the plagioclase *** results indicate that an evolved melt replenishing under the SWIR(51°E)drives the eruption over a short period of time.

关键词： plagioclase–phyric basalt plagioclase phenocrysts magmatic evolution SWIR

Evolution and diagenetic implications of framboids in the methane-related carbonates of the northern Okinawa Trough

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Acta Oceanologica Sinica 2021年第12期40卷 114-124页

作者： Kehong Yang zhimin zhu Yanhui Dong Fengyou Chu Weiyan Zhang Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

Authigenic carbonate samples were collected from the northern Okinawa *** on their carbon and oxygen isotopes,these samples were found to be methane-related carbonates precipitated by the anaerobic oxidation of methane(AOM).Petrological analysis revealed numerous framboidal pyrites that had been partly *** order to trace the variation and diagenetic information of these framboidal pyrites,their diameters and geochemical components were studied using an electron *** results showed that their diameters varied from 4μm to 17μm(n=60;geometric mean of 9.9μm)and were of a normal *** diameters of single pyrite that formed the framboidal pyrites varied from 1μm to 2μ*** framboidal pyrites with diameters of 6–14μm accounted for~80%of the *** geometric mean of 9.9μm indicates that they are probably diagenetic pyrites that were precipitated in a lower dysoxic environment(weakly oxygenated bottom waters).The S/Fe ratio of the framboidal minerals ranged from 0 to 1.67,and the pyrite content of single framboid varied between 0%and 86.4%.Therefore,numerous pyrites were oxygenated to iron oxides or oxyhydroxides,and were retained as pseudomorphism *** size of framboidal pyrites precipitated in cold seeps can be used to trace the redox environment;however,acquisition of additional data via investigation of different cold seeps is necessary to obtain more persuasive results.

关键词： framboidal pyrite grain size S/Fe ratio methane-related carbonate

Petrology and geochemistry of cold seep carbonates from the northern Okinawa Trough,East China Sea:implications to early diagenesis

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Journal of Oceanology and Limnology 2022年第4期40卷 1388-1403页

作者： Kehong YANG zhimin zhu Yanhui DONG Weiyan ZHANG Fengyou CHU Key Laboratory of Submarine Geosciences&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China

Carbonate samples were collected from the northern Okinawa Trough in the East China Sea in *** petrology,mineralogy,carbon and oxygen isotopes,and rare earth elements(REEs)of these samples were ***,high-Mg calcite,and dolomite were the main carbonate minerals,the contents of which varied greatly among the carbonate *** observations revealed the common occurrence of framboidal ***δ^(13)C values of carbonates varied from-53.7‰to-39.3‰(average of-47.3‰based on Vienna Pee Dee Belemnite(V-PDB),n=9),and theδ^(18)O values ranged from 0.6‰to 3.4‰(average of 1.9‰;V-PDB,n=9).The carbon and oxygen isotope characteristics indicated that the carbonates precipitated during the anaerobic oxidation of *** carbon source was a mixture of thermogenic methane and biogenic methane,possibly with a greater contribution from the *** oxygen isotope data showed that gas hydrate dissociation occurred during carbonate *** Ce anomalies suggested that the carbonates precipitated in an anoxic environment.A slight enrichment of middle REEs(MREEs)could be attributable to the early *** structures,minerals,oxygen isotopes,and MREEs all indicated that the carbonates experienced some degree of early ***,the infl uence of early diagenesis should be considered when using geological and geochemical proxies to reconstruct original methane seepage environments.

关键词： authigenic carbonate carbon and oxygen isotopes rare earth elements(REEs) anaerobic oxidation of methane(AOM) northern Okinawa Trough

Zircon U-Pb age, Trace Element, and Hf Isotopic Compositions of Nordmarkite in the Lizhuang Rare Earth Element Deposit in the Western Margin of the Yangtze Block

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 225-240页

作者： ZHOU Jiayun TAN Hongqi GONG Daxin zhu zhimin LUO Liping Institute of Multipurpose Utilization of Mineral Resources Chinese Academy of Geological Sciences Chengdu 610041

The Mianning-Dechang （MD） rare earth element （REE） belt, located in the northern Kangdian axis （KDA） in the western margin of the Yangtze platform, is one of the most economically significant REE mineral belts in China. REE mineralization is associated with Himalayan carbonatite- alkaline complexes. The Lizhuang nordmarkite occurred in the northern part of the MD REE belt. The majority of zircons from the Lizhuang nordmarkite are characterized by pronounced positive Ce yet slightly negative Eu anomalies and high U/Yb. Moreover, all zircons have stable Hf isotopic compositions with initial 176Hf/177Hf ratios ranging from 0.282739 to 0.282808 and an average value of 0.282773. The negative Lu/Hf and positive till（t） range from -0.98 to -0.94 （average value of -0.96） and from -0.56 to 1.89 （the majority is positive, with an average of 0.66）, respectively. These characteristics indicate that the rock is derived from an enriched mantle and subducted material. LA-ICP-MS analysis of the zircons from the intrusion yields a weighted mean 2~6pb/23SU age of 28.57~0.61Ma. During this period, the tectonic activity in the KDA is not plate subduction but an intraplate tectonic exhibiting fold-thrust and strike-slip behaviors in the western marginal zone of the Yangtze platform （WMYB）. We suggest the possibility of an existing eastward old slab subduction under WMYB combined with a regional tectonic evolution. The Lizhuang nordmarkite may be derived from an enriched mantle beneath the western part of the Yangtze craton, which originated from the remelting of the Tethys subducting slab, because of the Himalayan strike-slip that formed a special type of REE deposit called strike-slip-type REE deposits.

关键词： nordmarkite REE deposit Hf isotopic characteristics of zircon Lizhuang

Termination Time of the Emeishan Basalts in the Buotuo Region, SW China

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2448-2450页

作者： TAN Hongqi NI Zhiyao zhu zhimin XU Gang ZHANG Jiong College of Earth Sciences Chengdu University of Technology Institute of Multipurpose Utilization of Mineral Resources Chinese Academy of Geological Sciences Northwest Sichuan Geological Team Sichuan Geology and Mineral Bureau

Objective The Emeishan Large Igneous Province(LIP) is considered to represent a major Later Permian basaltic magmatism in the western margin of the Yangtze Block in South China. Previous geochronological studies on mafic intrusion and felsic ignimbrite have assigned an eruption age of 259–263 Ma for the Emeishan LIP(Zhong et al., 2010), accompanied by regional domal uplift(Mabi Awei et al., 2017). The Xuanwei Formation was formed after the termination of the Emeishan flood basalt volcanism. The uppermost silicic members in the center of the LIP were

关键词： MS SW China Pb ICP

Elemental Compositions of Clinopyroxenes from Southern Okinawa Trough Basalt:Implications for Magmatism and Structural Environment in an Initial Back-Arc Basin

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Journal of Ocean University of China 2024年第3期23卷 643-653页

作者： GUO Kun ZHAI Shikui FAN Di ZHANG Xia ZHANG Yu zhu zhimin Laoshan Laboratory Qingdao 266237China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Key Laboratory of Submarine Geosciences&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China

The major and trace elemental compositions of clinopyroxene from basalt were used to characterize the nature of the primitive magma and structural environment beneath the southern Okinawa Trough(SOT),which is an initial back-arc basin at a continental *** clinopyroxenes in the basalt were augite with variable Mg^(#)contents(73.37-78.22).The regular variations in major oxide contents(i.e.,CaO,FeO,TiO_(2),and Cr)with decreasing Mg#implied that the clinopyroxenes evolved from being enriched in Mg,Ca,and Cr to being enriched in Fe and *** clinopyroxenes had relatively low rare earth element concentrations(7.51×10^(-6) to 12.68×10^(-6))and negative Eu anomalies(δEu=0.67-0.95).The Kd_(cpx) values of clinopyroxenes(0.2-0.26),which were used to examine whether the clinopyroxene was equilibrated with its host basalt,demonstrate that these clinopyroxene phenocrysts were not captured crystals but were instead produced by crystallization differentiation of the *** calculated clinopyroxene crystallization temperatures showed a narrow range of 990-1061℃,and their crystallization pressures ranged from 2.0 to 3.2 *** geochemistry features of these clinopyroxenes indicated that the parent magma belonged to the subalkaline tholeiitic magma series and suggested that the magma experienced crystallization differentiation of olivine,plagioclase,and clinopyroxene,where the crystallization of plagioclase occurred earlier than that of *** with geophysical data,this research on primitive magma and its crystallization differentiation from clinopyroxene indicates that the SOT is in the stage of‘seafloor spreading’and that basaltic rocks produced from tholeiitic magma represent the generation of oceanic crust.

关键词： trace elements clinopyroxenes southern Okinawa Trough seafloor spreading back-arc basin

Luku Alkali Syenite in the Hongge Ore District,SW China:Geochemistry,Geochronology and Metallogenic Significance

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Acta Geologica Sinica(English Edition) 2022年第3期96卷 875-890页

作者： ZHOU Jiayun LIU Yingdong XU Li zhu zhimin GONG Daxing JIANG Xiaoli Technology Innovation Center of Rare Earth Resources Development and Utilization Chinese Geological SurveyChengdu 610041China Institute of Multipurpose Utilization of Mineral Resources Chinese Academy of Geological SciencesChengdu 610041China

Luku alkali syenite is distributed throughout the southern end of the Hongge basic-ultrabasic intrusion in Panzhihua,Sichuan,SW *** LA-ICP-MS,the alkali syenite intrusion yielded a zircon U-Pb age of_(2)64.5±1.6 Ma,concordant with the ages of the E’meishan large igneous province(260 Ma).The intrusion displayed silica-saturated,Al-adequate and alkali-rich signatures,with SiO_(2)62.07%-64.04%,Al_(2)O_(3)16.26%-16.79%and Na_(2)O+K_(2)O 9.17%-9.91%(averaging 9.31%).The rock falls into the alkaline zone on the SiO_(2)-***,as well as in the potassium zone on the K_(2)O-Na_(2)O diagram,indicating a potassium alkaline *** rock has a low total REE concentration and showed enrichment in LREE(LREE/HREE=7.06-7.95),typical negative Eu anomalies(δEu=0.73-0.80),trace element deficiencies in LILEs(Ba,K,Sr,Zr)and enrichment in HFSEs(Th,U,Nd,Sm,Ta and Nb),displaying crust and mantle element *** show a strong positive Ce anomaly and negative Eu anomaly,similar to the characteristics of crustal source magmatic zircon,however the(Lu/Gd)N ratio ranges from 1.48 to 3.17,and the(Yb/Sm)N ratio ranges from 38.49 to 77.15,which are similar to the characteristics of mantle-derived magmatic *** the La/Yb-δEu correlation diagram,the data plots near the boundary between crust type and crust-mantle *** the combined‘trinity’spatiotemporal relationship of Indosinian intermediate-acid alkali intrusive rocks in the Panxi area with E’meishan basalt and basic-ultrabasic intrusive rocks,the regional tectonic evolution and the partial melting model of the most intraplate magma sources,we believe that the Luku alkali syenite in Sichuan was formed from the partial melting of a crust-mantle source material,due to underplating of the mantle plume basic magma.

关键词： alkali syenite mantle plume LA-ICP-MS dating of zircon REE mineralization Hongge ore deposit

Adakitic rocks and destruction of the North China Craton:Evidence from experimental petrology and geochemistry

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Science China Earth Sciences 2011年第6期54卷 858-870页

作者： XIONG XiaoLin LIU XingCheng zhu zhimin LI Yuan XIAO WanSheng SONG MaoShuang ZHANG Sheng WU JinHua Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

The general temporal-spatial consistency for the formation of adakitic rocks and lithospheric thinning in northern China provide a window to examine the processes and mechanism for the destruction of the North China *** experimental petrology data,this paper demonstrates that the adakitic rocks in northern China are the products of partial melting of middle-to high-potassic metabasalts at the base of the lower continent *** on the TiO2 solubility model,many adakitic rocks in Dabie,Jiaodong and the northern part of the craton appear to have been saturated with *** indicates the presence of a Ti-rich accessory phase in their source *** phase must be rutile based on the decreasing Nb/La with increasing La/Yb in the adakitic *** adakitic magmas were,thus,derived from a depth of more than 50 km,based on pressures (higher than 1.5 GPa) for the stability of rutile in a metabasalt *** present-day crustal thickness is generally only 35 km,we suggest that the destruction of the North China Craton may have led to at least 15 km of thinning or delamination of the crust.

关键词： adakitic rocks North China Craton crustal thinning rutile experimental petrology

Engineering in-plane silicon nanowire springs for highly stretchable electronics

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Journal of Semiconductors 2018年第1期39卷 2-15页

作者： Zhaoguo Xue Taige Dong zhimin zhu Yaolong Zhao Ying Sun Linwei Yu National Laboratory of Solid State Microstructures/School of Electronic Science and Engineering/Collaborative Innovation Center of Advanced Microstructures Nanjing University

Crystalline silicon（c-Si） is unambiguously the most important semiconductor that underpins the development of modern microelectronics and optoelectronics, though the rigid and brittle nature of bulk c-Si makes it difficult to implement directly for stretchable applications. Fortunately, the one-dimensional（1 D） geometry, or the line-shape, of Si nanowire（SiNW） can be engineered into elastic springs, which indicates an exciting opportunity to fabricate highly stretchable 1 D c-Si channels. The implementation of such line-shape-engineering strategy demands both a tiny diameter of the SiNWs, in order to accommodate the strains under large stretching, and a precise growth location, orientation and path control to facilitate device integration. In this review, we will first introduce the recent progresses of an in-plane self-assembly growth of SiNW springs, via a new in-plane solid-liquidsolid（IPSLS） mechanism, where mono-like but elastic SiNW springs are produced by surface-running metal droplets that absorb amorphous Si thin film as precursor. Then, the critical growth control and engineering parameters, the mechanical properties of the SiNW springs and the prospects of developing c-Si based stretchable electronics, will be addressed. This efficient line-shape-engineering strategy of SiNW springs, accomplished via a low temperature batch-manufacturing, holds a strong promise to extend the legend of modern Si technology into the emerging stretchable electronic applications, where the high carrier mobility, excellent stability and established doping and passivation controls of c-Si can be well inherited.

关键词： c-Si nanowires in-plane solid-liquid-solid self-assembly stretchable electronics

Ore Minerals and Genesis of Lala Copper Deposit,Sichuan Province

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地学前缘 2009年第S1期16卷 172-173页

作者： zhimin zhu Institute of Multipurpose Utilization of Mineral Resources,Chinese Academy of Geological Sciences,Chengdu 610041,China.

The Lala Cu deposit in Sichuan Province is one of the most important large deposits in SW China,both in terms of Cu and associated Au-Mo-Co-REE-Fe. Systematic ore petrology study shows that ore minerals are mainly composed of hydrothermal magnetite,chalcopyrite and *** wall-rock alterations include biotitization,silicification, carbonatation,albitization,potash feldspathization, apatitation,actinolitation and fluoritation,et al. The Pyrite and magnetite have euhedral-subhedral crystalline grained texture and the chalcopyrite

关键词： ore mineral ore genesis Iron Oxide-Cu-Au deposit(lOCG) Lala copper deposit