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广西木论国家级自然保护区铁榄群落优势种群的生态位研究 被引量:17
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作者 钟军弟 李先琨 +3 位作者 叶铎 向悟生 吕仕洪 张建亮 《植物资源与环境学报》 CAS CSCD 2009年第3期38-43,共6页
对广西木论国家级自然保护区铁榄〔Sinosideroxylon pedunculatum (Hemsl.) H.Chuang〕群落优势种群的重要值进行了测定,并利用Levins和Hurlbert的生态位宽度指标及百分率相似性指数、Pianka和王刚的生态位重叠指数对这些优势种群的生... 对广西木论国家级自然保护区铁榄〔Sinosideroxylon pedunculatum (Hemsl.) H.Chuang〕群落优势种群的重要值进行了测定,并利用Levins和Hurlbert的生态位宽度指标及百分率相似性指数、Pianka和王刚的生态位重叠指数对这些优势种群的生态位进行了研究。结果表明,该铁榄群落中有11个优势种群,其中铁榄的重要值总和最大(319.27%),小栾树〔Boniodendron minus (Hemsl.) T.Chen〕、日本女贞(Ligustrum japonicum Thunb.)和广西密花树(Rapanea kwangsiensis Walker)的重要值总和也均在200%以上,掌叶木〔Handeliodendron bodinieri (Lévl.) Rehd.〕、朴树(Celtis sinensis Pers.)和榔榆(Ulmus parvifolia Jacq.)的重要值总和较小,均在70%以下。生态位宽度值较大的优势种群为铁榄、广西密花树、小栾树、红背山麻杆〔Alchornea trewioides (Benth.) Müll.Arg.〕及九里香(Murrayaexotica L.Mant.),生态位宽度值最小的是掌叶木。用3种方法测得的生态位重叠结果基本一致;生态位重叠值较大的种对有铁榄-小栾树、小栾树-日本女贞及小栾树-广西密花树等;生态位重叠值较小的种对有掌叶木-朴树和掌叶木-榔榆等。研究结果显示,重要值大的优势种群生态位宽度通常较大,生态位宽度大的优势种群间通常生态位重叠较大,但喀斯特生境的高异质性也可使生态位宽度较小的种对间产生较大的生态位重叠;该铁榄种群中大部分优势种群的生态位相似值和重叠值较高,说明该铁榄群落优势种群间竞争较强,群落结构可能具有一定的不稳定性。 展开更多
关键词 广西木论国家级自然保护区 铁榄群落 优势种群 重要值 生态位宽度 生态位重叠
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深圳市大南山地区铁榄群落研究 被引量:5
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作者 刘军 罗连 +3 位作者 吴桂萍 张冰 詹惠玲 廖文波 《热带亚热带植物学报》 CAS CSCD 北大核心 2010年第5期523-529,共7页
对深圳市大南山地区的主要植被进行调查研究。结果表明,铁榄(Sinosideroxylon wightianum)常生长在瘠薄坡地、陡峭沟谷中,是该地区最重要的天然林群落,常组成单优势群落,呈斑块状分布,也是该地区存留的少数次生常绿阔叶林群落之一;大南... 对深圳市大南山地区的主要植被进行调查研究。结果表明,铁榄(Sinosideroxylon wightianum)常生长在瘠薄坡地、陡峭沟谷中,是该地区最重要的天然林群落,常组成单优势群落,呈斑块状分布,也是该地区存留的少数次生常绿阔叶林群落之一;大南山地区的铁榄群落有10个主要类型,铁榄是常绿阔叶林植被的主要特征种;大南山地区铁榄群落结构简单,物种分布不均匀,物种多样性指数差异较大;铁榄以Ⅱ级小树为主,兼有Ⅰ级苗木和Ⅲ级壮树,表明铁榄在群落中的优势度仍将保持较长一段时间;铁榄与漆树等物种间的种间联结关系薄弱,表明群落处于群落演替的早期发育阶段。 展开更多
关键词 铁榄 植物群落 深圳大南山地区
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Mechanism of lime decomposing Al_(2)O_(3)-containing fayalite melt
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作者 Hui-chuan REN Xiao-bo MIN +6 位作者 Yong KE Long-gong XIA Yun-yan WANG Cong PENG Yun LI Rong-he TAN Chuan-fu ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第11期3707-3720,共14页
A method to upgrade the iron grade in copper slag was proposed using lime to decompose Al_(2)O_(3)-containing fayalite melt(AFMT).Thermodynamic calculations indicated that adjusting the CaO/AFMT ratio can yield a resi... A method to upgrade the iron grade in copper slag was proposed using lime to decompose Al_(2)O_(3)-containing fayalite melt(AFMT).Thermodynamic calculations indicated that adjusting the CaO/AFMT ratio can yield a residual melt with a FeO concentration of 75−88 wt.%and produce Ca_(2)SiO_(4).In-situ observations suggested that the reaction was impeded in some way.Quenching experiments revealed that the initial reaction products consisted of calcium ferrite compounds and FeO−CaO melt.At the FeO−CaO melt/AFMT interface,Ca_(2)SiO_(4) particles precipitated,forming a dense Ca_(2)SiO_(4) film that significantly impeded mass transfer.Although trace amounts of Al_(2)O_(3) in AFMT temporarily enhanced mass transfer,they were insufficient to overcome this retardation effect.The decomposition reaction was far from achieving equilibrium,demonstrating a self-retardation effect.Measures must be implemented to eliminate this self-retardation effect and enhance the efficiency of reaction kinetics. 展开更多
关键词 LIME Al_(2)O_(3)-containing fayalite melt Ca_(2)SiO_(4)film self-retardation mass transfer
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深圳大南山地区土壤性质及其生态效应分析 被引量:2
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作者 刘军 邓星 +3 位作者 韩博 王向前 吴桂萍 席嘉宾 《安徽农业科学》 CAS 北大核心 2011年第24期14679-14683,共5页
[目的]为南山公园的优势种群——铁榄群落的建设和管理提供理论依据。[方法]采用环刀法,对深圳大南山土壤的理化性质现状进行取样调查。[结果]大南山土壤母岩为石英砂岩,土壤中多石砾。土壤孔隙度50%左右,质地为壤土。土壤呈强酸性,pH... [目的]为南山公园的优势种群——铁榄群落的建设和管理提供理论依据。[方法]采用环刀法,对深圳大南山土壤的理化性质现状进行取样调查。[结果]大南山土壤母岩为石英砂岩,土壤中多石砾。土壤孔隙度50%左右,质地为壤土。土壤呈强酸性,pH平均为4.75。土壤有机质、全氮、碱解氮和速效磷平均含量分别为12.48 g/kg、0.49 g/kg、84.20 mg/kg和3.31 mg/kg,在剖面中的含量均随土层加深而下降。土壤有机质和全氮、碱解氮、速效磷呈显著正相关关系,相关系数分别为0.93、0.85和0.72。0~60 cm土层现实贮水量为688.94 t/hm2,最大保水能力为1 506.07 t/hm2,有机质、速效氮、磷贮量分别为63.31 t/hm2、720.30 kg/hm2和28.39 kg/hm2。[结论]土壤理化性质现状为深圳大南山的优势种群——铁榄群落的产生奠定一定的基础。 展开更多
关键词 深圳大南山 土壤 理化性质 铁榄
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Recovery of valuable metals from spent lithium ion batteries by smelting reduction process based on FeO-SiO_2-Al_2O_3 slag system 被引量:39
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作者 任国兴 肖松文 +4 位作者 谢美求 潘炳 陈坚 王奉刚 夏星 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第2期450-456,共7页
NA novel smelting reduction process based on FeO-SiO2-Al2O3 slag system for spent lithium ion batteries with Al cans was developed, while using copper slag as the only slag former. The feasibility of the process and t... NA novel smelting reduction process based on FeO-SiO2-Al2O3 slag system for spent lithium ion batteries with Al cans was developed, while using copper slag as the only slag former. The feasibility of the process and the mechanism of copper loss in slag were investigated. 98.83% Co, 98.39% Ni and 93.57% Cu were recovered under the optimum conditions of slag former/battery mass ratio of 4.0:1, smelting temperature of 1723 K, and smelting mass ratio of time of 30 min. The FeO-SiO2-Al2O3 slag system for the smelting process is appropriate under the conditions of m(FeO):m(SiO2)=0.58:1?1.03:1, and 17.19%?21.52% Al2O3 content. The obtained alloy was mainly composed of Fe-Co-Cu-Ni solid solution including small amounts of matte. The obtained slag mainly consisted of fayalite and hercynite. Meanwhile, the mechanism of copper loss is the mechanical entrainment from strip-like fayalite particles in the main form of copper sulfide and metallic copper. 展开更多
关键词 lithium ion battery smelting reduction cobalt nickel copper slag FAYALITE
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Improvement of carbothermic reduction of nickel slag by addition of CaCO3 被引量:5
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作者 Xiao-ming LI Zhen-yu WEN +2 位作者 Yi LI Hai-bo YANG Xiang-dong XING 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第12期2658-2666,共9页
The effect of CaCO3 addition on the carbothermic reduction of nickel slag was studied,and the mechanism of CaCO3 in improving the reduction was analyzed.The results showed that when the CaCO3 content added to the slag... The effect of CaCO3 addition on the carbothermic reduction of nickel slag was studied,and the mechanism of CaCO3 in improving the reduction was analyzed.The results showed that when the CaCO3 content added to the slag was increased from 0 to 8 wt.%,initiation temperature of the carbothermic reaction decreased from 1100 to 1000℃,the temperature reaching the maximum reduction rate decreased from 1150 to 1100℃,and the reduction degree of the nickel slag increased from 58%to 88%.The iron particles in the reduced nickel slag were coarsened and the X-ray diffraction intensity of metallic iron peaks increased,confirming that the addition of CaCO3 was beneficial to the reduction of nickel slag and recovery of iron. 展开更多
关键词 nickel slag FAYALITE carbothermic reduction CACO3
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Interaction mechanism between arsenate and fayalite-type copper slag at high temperatures 被引量:3
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作者 Da-wei WANG Zong-wen ZHAO +3 位作者 Zhang LIN Yan-jie LIANG Li KANG Bing PENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第2期709-720,共12页
The interaction mechanism between sodium arsenate and fayalite-type copper slag at 1200℃was investigated through XRD,XPS,HRTEM,TCLP and other technical means and methods.The results indicated that the proportions of ... The interaction mechanism between sodium arsenate and fayalite-type copper slag at 1200℃was investigated through XRD,XPS,HRTEM,TCLP and other technical means and methods.The results indicated that the proportions of sodium arsenate in the slag and flue gas phases were approximately 30%and 70%,respectively.The addition of sodium arsenate depolymerized the fayalite structure and changed it from a crystalline state to an amorphous state.The fayalite structural changes indicated that the[AsO_(4)]tetrahedron in sodium arsenate combined with the[SiO_(4)]tetrahedron and[FeO_(4)]tetrahedron through bridging oxygen to form a silicate glass structure.The TCLP test results of the samples before and after the high temperature reaction of fayalite and sodium arsenate showed that after high temperature reaction,fayalite could effectively reduce the leaching toxicity of sodium arsenate,reducing the leaching concentration of arsenic from 3025.52 to 12.8 mg/L before and after reaction,respectively. 展开更多
关键词 FAYALITE sodium arsenate depolymerization reaction silicate glass structure
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Effect of pyroxenite and olivine minerals as source of MgO in hematite pellet on improvement of metallurgical properties 被引量:6
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作者 Jagannath Pal Satadal Ghorai +3 位作者 Bikash Nandi Tapas Chakraborty Goutam Das T.Venugopalan 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3302-3310,共9页
Pelletization of hematite ore requires high fineness and very high induration temperature(~1325 ℃) owing to its poor diffusion bonding unlike magnetite ore. Further, high-alumina hematite pellets show very high red... Pelletization of hematite ore requires high fineness and very high induration temperature(~1325 ℃) owing to its poor diffusion bonding unlike magnetite ore. Further, high-alumina hematite pellets show very high reduction degradation index(RDI) during low temperature(500-650 ℃) reduction due to their volume expansion and lattice distortion. Noamundi(India) hematite ore contains very high Al2O3(2.3%) with adverse ratio of alumina to silica(~2) for which, it shows very high RDI. In this work, the acid pellets prepared from Noamundi ore fines of optimum Blaine fineness show good cold crushing strength(CCS). However, it shows very high RDI(77%). In order to reduce RDI, Mg O in form of two different gangue-containing fluxes, such as pyroxenite and olivine in varying quantities has been added. The optimum requirement and performance of these fluxes has been examined and compared. Both pyroxenite and olivine fluxed pellets show significant lowering of RDI(26% and 23%, respectively) and improvement of other properties, viz CCS, swelling indices etc with good reducibility(70%-77%). Finally, a good quality acidic hematite pellet was developed from high-alumina ore without using any lime which is very important charge material in combination of basic sinter in blast furnace. 展开更多
关键词 hematite pellet high-alumina ore reduction degradation index(RDI) pyroxenite flux olivine flux effect of MgO
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Effect of Foliar Spray of Fe, GA3, Cultivars and Their Interactions on Growth of Olive (Olea europaea L.) Transplants cvs. Khithairy and Sorany
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作者 Azad Ahmed Mayi Amira Salih Abdulrhman Zulaikha Ramazan Ibrahim 《Journal of Agricultural Science and Technology(B)》 2013年第5期358-368,共11页
The study was conducted at the nursery of Malta station/Duhok. Kurdistan region-lraq, during the season 2011 to study the effect of GA3 and Fe on vegetative growth of two year old of two olive (Olea europaea L.) cul... The study was conducted at the nursery of Malta station/Duhok. Kurdistan region-lraq, during the season 2011 to study the effect of GA3 and Fe on vegetative growth of two year old of two olive (Olea europaea L.) cultivars (Kithary and Sorany), the transplant were sprayed with four levels (0, 250, 500 and 750 mg L^-1 GA3) and four levels of chelated iron (0, 25, 50 and 75 mg Fe L^-1). Foliar application of GA3 at 500 mg Ll increased significantly stem diameter (mm), leaf number, increasing GA3 level up 750 mg L^-1 significantly increase shoot length (cm) plantl, leaf area. However, 50 mg Fe L^-1 increased significantly leaf number, leaf area, chlorophyll content, and when treated with 75 mg Fe L^-1 significantly increase stem diameter, shoot length cm plant^-1, leaf fresh weight (g), leaf dry weight (g). While, Kithary cultivar significant dominated Sorany cultivar of the most studied characteristics. The interactions between GA3, Fe and cultivars significantly affected on the most of the characteristics studied, foliar sprays of Kithary cultivar with 750 mg Ll GA^-1 and 0 mg Fe Ll significantly increase chlorophyll content and leaf area, and Kithary cultivar when treated only by 75 mg Fe Ll increase significantly plant high (cm), stem diameter (mm), leaf dry weight (g) and leaf fresh weight when compared with the control. 展开更多
关键词 FE GA3 CULTIVAR olive (Olea europaea L.) leaf nutrient analysis
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Petroqenesis of Subduction Zone and Dunite Bodies
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作者 Ayse Didem Klh9 《Journal of Earth Science and Engineering》 2012年第7期377-386,共10页
The dunite bodies, which extend as the direction of W-E, are exposed to the southeast of Elazlg located within the Eastern Taurus Belt of Turkey. Mafic-Ultramafic section in the Guleman ophiolite consists ofdunite whi... The dunite bodies, which extend as the direction of W-E, are exposed to the southeast of Elazlg located within the Eastern Taurus Belt of Turkey. Mafic-Ultramafic section in the Guleman ophiolite consists ofdunite which containing disseminated chromites, wehrlite, gabbros (isotrope gabbro and layered gabbro) and clinopyroxenite. Dunite blocks above the harzburgite massif have irregular contacts with the enclosing peridotites. Dunite blocks are generally around a few of meters. Dunite blocks consist of gabbro and pyroxenite patches. The origin of dunite blocks are belong to the transition zone of harzburgitic ophiolites which is located at the base of the mafic layered section. They are entirely or largely magmatic formed by olivine and chromite ponds at the base of the crustal magma chamber. The rather around of rock pieces within dunite bodies are foliated such as features have been ascribed to the ophiolite being impregnated by and reacting with a melt. Rocks in the bodies show depleted in incompatible trace elements such as Ba, Nbet al., characteristic of subduction related magma. Furthermore, the high LREE/HREE and high Rb/Th ratios indicates a mantle that has been enrichmented by subduction. As a result, isotopic data, petrographic and geochemical of bodies's result suggest a parental magma derived from an enrichmed source of subduction zone. A few meters of the large dunite bodies, and ascribes to the central dunites a cumulative origin by fractionation from a picritic melt. 展开更多
关键词 Neotethyan TURKEY dnite bodies subduction zone OPHIOLITE geochemistry.
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Homologous temperature of olivine: Implications for creep of the upper mantle and fabric transitions in olivine 被引量:5
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作者 WANG Qin 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第6期1138-1156,共19页
The homologues temperature of a crystalline material is defined as T/Tm, where T is temperature and Tm is the melting (solidus) temperature in Kelvin. It has been widely used to compare the creep strength of crystal... The homologues temperature of a crystalline material is defined as T/Tm, where T is temperature and Tm is the melting (solidus) temperature in Kelvin. It has been widely used to compare the creep strength of crystalline materials. The melting temperature of olivine system, (Mg,Fe)2SiO4, decreases with increasing iron content and water content, and increases with confining pressure. At high pressure, phase transition will lead to a sharp change in the melting curve of olivine. After calibrating previous melting experiments on fayalite (Fe2SiO4), the triple point of fayalite-Fe2SiO4 spinel-liquid is determined to be at 6.4 GPa and 1793 K. Using the generalized means, the solidus and liquidus of dry olivine are described as a function of iron content and pressure up to 6.4 GPa. The change of T/Tm of olivine with depth allows us to compare the strength of the up- per mantle with different thermal states and olivine composition. The transition from semi-brittle to ductile deformation in the upper mantle occurs at a depth where T/Tm of olivine equals 0.5. The lithospheric mantle beneath cratons shows much smaller T/Tm of olivine than orogens and extensional basins until the lithosphere-asthenosphere boundary where T/Tm 〉 0.66, suggesting a stronger lithosphere beneath cratons. In addition, T/Tm is used to analyze deformation experiments on olivine. The results indicate that the effect of water on fabric transitions in olivine is closely related with pressure. The hydrogen-weakening effect and its relationship with T/Tm of olivine need further investigation. Below 6.4 GPa (〈200 kin), T/TIn of olivine controls the transition of dislocation glide from [100] slip to [001] slip. Under the strain rate of 10-12-10-15 s-1 and low stress in the upper mantle, the [100](010) slip system (A-type fabric) becomes dominant when T/TIn〉 0.55-0.60. When T/Tm〈 0.55-0.60, [001] slip is easier and low T/Tm favors the operation of [001](100) slip system (C-type fabric). This is consistent with the widely observed A-type olivine fabric in naturally deformed peridotites, and the C-type olivine fabric in peridotites that experienced deep subduction in ultrahigh-pressure metamorphic terranes. However, the B-type fabric will develop under high stress and relatively low T/Tm. Therefore, the homologues temperature of olivine established a bridge to extrapolate deformation experi- ments to rheology of the upper mantle. Seismic anisotropy of the upper mantle beneath cratons should be simulated using a four-layer model with the relic A-type fabric in the upper lithospheric mantle, the B-type fabric in the middle layer, the newly formed A- or B-type fabric near the lithosphere-asthenosphere boundary, and the asthenosphere dominated by diffusion creep below the Lehmann discontinuity. Knowledge about transition mechanisms of olivine fabrics is critical for tracing the water distribution and mantle flow from seismic anisotropy. 展开更多
关键词 OLIVINE Homologous temperature Lattice preferred orientation Water Seismic anisotropy Upper mantle
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Surface microstructures of lunar soil returned by Chang’e-5 mission reveal an intermediate stage in space weathering process 被引量:1
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作者 Jian-Gang Guo Tianping Ying +8 位作者 Hanbin Gao Xu Chen Yanpeng Song Ting Lin Qinghua Zhang Qiang Zheng Chunlai Li Yigang Xu Xiaolong Chen 《Science Bulletin》 SCIE EI CAS CSCD 2022年第16期1696-1701,M0004,共7页
The lunar soils evolution over time is mainly caused by space weathering that includes the impacts of varying-sized meteoroids and charged particles implantation of solar/cosmic winds as well.It has long been establis... The lunar soils evolution over time is mainly caused by space weathering that includes the impacts of varying-sized meteoroids and charged particles implantation of solar/cosmic winds as well.It has long been established that space weathering leads to the formation of outmost amorphous layers(50–200 nm in thickness)embedded nanophase iron(npFe^(0))around the mineral fragments,albeit the origin of the npFe^(0) remains controversial.The Chang’e-5(CE-5)mission returned samples feature the youngest mare basalt and the highest latitude sampling site,providing an opportunity to seek the critical clues for understanding the evolution of soils under space weathering.Here,we report the surface microstructures of the major minerals including olivine,pyroxene,anorthite,and glassy beads in the lunar soil of CE-5.Unlike the previous observations,only olivine in all crystals is surrounded by a thinner outmost amorphous SiO_(2) layer(∼10 nm thick)and embedded wüstite nanoparticles FeO(np-FeO,3–12 nm in size)instead of npFe^(0).No foreign volatile elements deposition layer and solar flare tracks can be found on the surface or inside the olivine and other minerals.This unique rim structure has not been reported for any other lunar,terrestrial,Martian,or meteorite samples so far.The observation of wüstite FeO and the microstructures support the existence of an intermediate stage in space weathering for lunar minerals by thermal decomposition. 展开更多
关键词 Lunar soil Wüstite FeO Nanoparticle Nanophase Fe Amorphous rim
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High-pressure experimental verification of rutile-ilmenite oxybarometer: Implications for the redox state of the subduction zone 被引量:2
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作者 TAO RenBiao ZHANG LiFei +2 位作者 Vincenzo STAGNO CHU Xu LIU Xi 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第10期1817-1825,共9页
The more oxidized mantle peridotites above subducting slabs than stable continental areas have been attributed to the infiltration of some oxidizing fluids released from the subducting slabs. However, knowledge for th... The more oxidized mantle peridotites above subducting slabs than stable continental areas have been attributed to the infiltration of some oxidizing fluids released from the subducting slabs. However, knowledge for the redox states of the slabs itself is very limited. Until now, few oxybarometers can be directly used to constrain the redox states of the subducting slabs.The rutile-ilmenite oxybarometer was proposed and successfully applied to constrain the oxygen fugacity of mantle assemblages.However, its application to rocks equilibrated at crustal P-T conditions has been hampered by some uncertainties in an early solid solution model of ilmenite. With a newly-released solid solution model for the ilmenite, we have conducted high-P experiments(at 3 and 5 GPa, and 900–1300°C) to test the accuracy of this oxybarometer. The experiments were performed with their oxygen fugacities controlled by the CCO buffer(i.e., C+O_2=CO_2). We demonstrated that the oxygen fugacities calculated for our high-P experimental products by using the rutile-ilmenite oxybarometer were in excellent agreement with the fO_2 dictated by the CCO buffer, suggesting a wide applicability of this oxybarometer to crust rocks. As examples, the rutile-ilmenite oxybarometer has been used to constrain the oxygen fugacities of some metamorphic rocks such as eclogite, granulite and amphibolite usually observed from the subduction zones. 展开更多
关键词 High-pressure experiment Ilmenite-rutile oxybarometer Oxygen fugacity Subduction zone
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