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Chinese Journal Of Geochemistry 2009年第1期28卷 28-43页

作者： YANG Xiaoyong CAS key laboratory of Crust-Mantle materials and environments School of Earth ＆ Space Sciences University of Science ＆ Technology of China Hefei 230026 China State key laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China

On the basis of the geological and geochemical studies, including chemical analysis of bulk rocks, rare-earth and trace element studies, fluid inclusion, and S and O isotopic analyses, the authors described the geological background of the deposit in detail and presented significant proofs for the conditions of formation of the Shaxi porphyry copper-gold deposit. Compared with other large and supper-large porphyry copper deposits in China and the adjacent Cu-Au mineralized areas, the ore-forming processes and conditions were analyzed; and the possibility of forming large porphyry copper deposits in the Shaxi area was discussed. The present study indicated that the ore-forming fluid and material were mainly of magmatic origin, while meteoric water played a certain role in the ore-forming processes. Interactions between subducting and overriding plates provided a major driving force for the formation of igneous rocks and the deposition of metal elements in East China since Jurassic. Based on the geo- chemical data of the Shaxi intrusive, it is found that the copper (gold) mineralization is closely related to the genesis of adakite-like intrusive in the Shaxi area. This adakite-like intrusive was formed in the subduction environment as a result of the subduction of the West Pacific plate toward the East China continent, where there is a great potentiality to form a large porphyry copper deposit.

关键词：斑岩金成矿物化环境温度

sRNAminer:多功能的植物小RNA分析工具

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Science Bulletin 2024年第6期69卷 784-791页

作者：李冠良陈程杰陈佩珂 Blake C.Meyers 夏瑞 State key laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of HorticultureSouth China Agricultural UniversityGuangzhou 510640China Guangdong laboratory for Lingnan Modern Agriculture South China Agricultural UniversityGuangzhou 510640China key laboratory of Biology and Germplasm Enhancement of Horticultural Crops in South China Ministry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou 510640China Center Saint LouisMO 63132USA Division of Plant Science and technology University of Missouri-ColumbiaColumbiaMO 65211USA

Small RNAs(sRNAs),found extensively in plants,play an essential role in plant growth and *** various sRNA analysis tools have been developed for plants,the use of most of them depends on programming and command-line environments,which is a challenge for many wet-lab ***,current sRNA analysis tools mostly focus on the analysis of certain type of sRNAs and are resource-intensive,normally demanding an immense amount of time and effort to learn the use of numerous tools or scripts and assemble them into a workable pipeline to get the final ***,we present sRNAminer,a powerful stand-alone toolkit with a user-friendly interface that integrates all common functions for the analysis of three major types of plant sRNAs:microRNAs(miRNAs),phased small interfering RNAs(phasiRNAs),and heterochromatic siRNAs(hc-siRNAs).We constructed a curated or"golden"set of MIRNA and PHAS loci,which was used to assess the performance of sRNAminer in comparison to other existing *** results showed that sRNAminer outperformed these tools in multiple aspects,highlighting its *** addition,to enable an efficient evaluation of sRNA annotation results,we developed Integrative Genomics Viewer(IGV)-sRNA,a modified genome browser optimized from IGV and we incorporated it as a functional module in ***-sRNA can display a wealth of sRNA-specific features,enabling a more comprehensive understanding of sRNA *** and IGV-sRNA are both platform-independent software that can be run under all operating *** are now freely available at https://***/kli28/sRNAminer and https://***/CJchen/IG V-sRNA.

关键词： sRNAminer sRNA analysis miRNA PhasiRNA hc-siRNA IGV-sRNA

Water contents and hydrogen isotopes in nominally anhydrous minerals from UHP metamorphic rocks in the Dabie-Sulu orogenic belt

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Chinese Science Bulletin 2013年第22期58卷 4384-4389页

作者： GONG Bing CHEN RenXu ZHENG YongFei CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space Sciences University of Science and Technology of China

A continuous flow method,by a combination of thermal conversion elemental analyzer(TC/EA)with isotope ratio mass spectrometry(MS),was developed to determine both H isotope composition and H2O concentration of ultrahigh-pressure(UHP)metamorphic rocks in the Dabie-Sulu orogenic *** using the developed step-heating technique,we have studied H2O concentration and H isotope composition of the different forms of water(structural OH and molecular H2O)in *** quantitative measurements of H2O concentration and H isotope composition of minerals in UHP metamorphic rocks from several typical outcrops indicate that the gneisses can release more amounts of water than the eclogites during exhumation of the deeply subducted continental ***,by decompression dehydration at the contact between eclogite and gneiss,the released water could flow from the gneiss to the eclogite and result in significant hydration of the eclogite adjacent to the *** measured maximum water contents of minerals in eclogites indicate that garnet and omphacite have the maximum water solubilities of 2500and 3500 ppm,respectively,under the peak UHP metamorphic conditions.

关键词：超高压变质岩苏鲁造山带氢同位素矿物质无水水含量同位素组成利用开发

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Exploration and Sources of Bauxite Deposit in the Boloven Plateau, Southern Laos

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Journal of Earth Science 2019年第1期30卷 121-130页

作者： Yongzhen Long Xiaoyong Yang Mu Yang Dexian Zhang key laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationCentral South University School of Geosciences and Info-Physics Central South University CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space SciencesUniversity of Science and Technology of China

The Boloven bauxite deposit occurs either in the weathered basalt(alkali basalt and tholeiite), or in the Cretaceous sandstone. It is generally agreed that the bauxite deposits/laterites overlying the alkali basalt and tholeiite were derived from weathering of underlying basalt, however, the origin of bauxite deposit overlying the sandstone remains controversial. Chondrite-normalized REE patterns show that the bauxite ores/laterites overlying the sandstone exhibit quite similar chondrite-normalized REE patterns to those overlying the alkali basalt. Diagram of Al-Ti-Zr shows that the bauxite ores/laterites overlying the sandstone, tholeiite and alkali basalt are close to each other and to the calc-alkaline suite, however, significantly different from the sandstone and shales. Binary diagram of log Nb/Y vs log Zr/Ti further indicates that the parent rocks of bauxite ores/laterites overlying the sandstone belong to the suit of ultra-alkali to alkali basalt. Multivariate statistical analysis of geochemical data exhibit that the geochemical characteristics of HREE, Y, LREE and Al_2O_3 for bauxite ores/laterites overlying the sandstone are similar to those overlying the alkali basalt(15.7 Ma), obviously different from those overlying the tholeiite(1.2 to 0.5 Ma). Consequently, it can be inferred that the bauxite deposits/laterites overlying the sandstone were derived from the alkali basalt.

关键词： late ritic-type bauxite XRD datum processing exploration sources Boloven Plateau Laos

evaluation of Auto-Ignition Characteristics of Diesel Surrogate Fuels with the Same Derived Cetane Numbers at Changed Thermodynamic environments

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Journal of Thermal Science 2024年第4期33卷 1590-1606页

作者： ZHANG Cong GUAN Yuanhang HUANG Zhen HAN Dong key laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong UniversityShanghai200240China College of Smart Energy Shanghai Jiao Tong UniversityShanghai200240China Shanghai Non-carbon Energy Conversion and Utilization Institute Shanghai200240China

The ignition tendency of diesel fuels is highly sensitive to ambient conditions and fuel *** this study,the ignition characteristics of different diesel surrogate fuels with the same derived cetane numbers(DCN)were measured and compared in varied thermodynamic and oxidizing *** combustion pressures,heat release rates,ignition delays,and combustion delays of the test fuels were *** experimental results showed that the diesel surrogate fuels with the same DCNs exhibit similar ignition propensity at standard DCN test ***,for the test conditions of high cetane fuels,high ambient temperatures,and suficient oxygen concentrations,surrogate fuels with the same DCN have similar ignition behaviors,and using the DCN to evaluate fuel ignition tendency is ***,for the test conditions of low cetane fuels,low ambient temperatures,and reduced oxygen concentrations,different ignition behaviors are observed for the surrogate fuels with the same DCN,so at these conditions using DCN as the evaluation index for fuel ignition tendency may lead to higher uncertainty.

关键词： diesel fuels surrogate fuels derived cetane numbers constant volume combustion chamber

Geochemical characteristics of the Xuanwei Formation in West Guizhou:Significance of sedimentary environment and mineralization

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Chinese Journal Of Geochemistry 2010年第4期29卷 355-364页

作者： ZHANG Zhengwei YANG Xiaoyong LI Shuang ZHANG Zhongshan State key laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

The Upper Permian Xuanwei Formation widely occurs in western Guizhou,unconformably overlying the Emeishan basalts,and mainly consists of black *** is～170 m thick at Cuyudong Village,Weining County,West Guizhou,China,where the samples of black shale and sandy shale were collected and *** shales mainly contain SiO2,18.9%?44.1%,Al2O3,14.8%?52.8%,Fe2O3,1.0%?41.2%,LOI,3.2%?21.1%,TiO2,1.0%-6.7%,and MgO,0.2%?2.5%.The contents of all other major elements are lower than 1.0%.It is shown that the black shales have higher contents of Fe2O3 and LOI than normal *** siderites occurred in the black shales with higher contents of Fe2O3,which may be attributed to hydrothermal activities on *** analyzed shale samples have extremely high Ga,47.8×10-6-109.9×10-6(70.5×10-6 on average),higher than the industrial mining standard of Ga Resource Industry *** total contents of rare-earth elements(REE) of 9 black shale samples vary from 213×10-6 to 1460×10-6,suggesting that these black shales are enriched in *** shale-normalized REE patterns display both positive and negative Ce anomalies(Ce/Ce* from 0.5 to 1.7),revealing that the Xuanwei shales were precipitated under oxic and anoxic *** Rb-Sr chronological diagram of 6 shale samples in the Xuanwei Formation shows an age of 255±12 *** isotopic ratios(87Sr/86Sr)t0 range from 0.70635 to 0.70711,suggesting that these Xuanwei black shales might be derived from chemical weathering of the Emeishan basalts.

关键词：贵州西部地球化学特征宣威组成矿作用沉积环境峨眉山玄武岩黑色页岩稀土元素

KREEP-rich breccia in Chang'E-5 regolith and its implications

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Science China Earth Sciences 2023年第11期66卷 2473-2486页

作者： Aoxin MEI Yun JIANG Shiyong LIAO Jinting KANG Fang HUANG Weibiao HSU CAS key laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and space Sciences University of Science and Technology of ChinaHefei 230026China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Institute of Deep space Sciences Deep Space Exploration LaboratoryHefei 230026China

Lunar breccias provide crucial insights into the lithological diversity,shock processing and evolution of the lunar ***,we report a unique regolith breccia(CE5C0000YJYX070GP,hereafter CE5C)returned from the Chang'E-5(CE-5)***5C is one of the largest CE-5 breccias with a wide variety of lithologies,dominated by basaltic and mineral fragments as well as impact-melted clasts(including mid-Ti glasses,high-Al glasses,and crystal-bearing impact melt clasts).A comprehensive study of petrology and mineralogy on several representative clasts was conducted by integrating Scanning Electron Microscopy(SEM),Tescan Integrated Mineral Analysis(TIMA),Electron Probe Microanalysis(EPMA)and Laser Ablation Inductively Coupled Plasma Mass Spectrometry(LA-ICP-MS)*** is sufficient that CE5C is a mixed mare-highland regolith breccia,with a high percentage of KREEPy material(>20 vol.%),which has not been previously reported in other CE-5 *** mid-Ti impact glasses are characterized by high FeO(24.0 wt.%)and intermediate TiO_(2)(5.5 wt.%)contents,while the high-Al impact glasses have a chemical composition compatible with *** with the regional geological context of the CE-5 landing site,we propose that CE5C is likely derived from a mixed region between the P58/Em4 mare unit and its contiguous eastern *** the difficulty in assessing the representativeness of CE5C,the substantial presence of KREEPy material may provide valuable clues to the provenance of exotic ejecta,including the identification of unrecognized source craters situated in the eastern periphery of the sampling unit.

关键词： Chang'E-5 Regolith breccia Impact glasses KREEP Mare basalts

Partial melting of the dry mafic continental crust: Implications for petrogenesis of C-type adakites

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Chinese Science Bulletin 2010年第22期55卷 2428-2439页

作者： HUANG Fang HE YongSheng Institute of Geochemistry and Petrology ETH Zurich 8092 Zurich Switzerland CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

C-type adakites have been commonly considered as a result of partial melting of the mafic lower continental crust (LCC) at high pressure, as supported by high P-T experiments on hydrous basalts. However, because the mafic eclogitic LCC is generally dry, experiments on water-bearing materials cannot be used to constrain the melting processes of the dry mafic LCC. Due to the lack of systematic melting experimental studies on dry mafic rocks at crustal pressures, MELTs software was applied to simulating melting of the dry mafic LCC at 1–2 GPa. Comparison of model results with experimental data indicates that, when melting de-gree is greater than 20%, melts from the dry mafic LCC at 1–3 GPa cannot produce the C-type adakitic melt with high SiO2 con-tent (～70%). Although the limited experimental results about dry mafic rock melting at 1–2 GPa in the literature suggest that low degree melting (1.8 GPa, low-degree melting can produce dacitic melt with high K2O/Na2O (～1) if SiO2 content of the melt is controlled by residual garnet. Furthermore, the simulation also suggests that, if pressure is <1.8 GPa, abundant plagioclase (plg) in the residual phase may de-crease SiO2 content in the melt to below 62%, much lower than that of the C-type adakites observed in eastern China. Given the high P-T conditions required to produce melts with high SiO2 and extremely low HREE contents, such melts could easily be con-taminated by other crustal-derived melts, implying that the C-type adakites from eclogite melting could be less commonly ob-served in the outcrops than previously believed. Besides the interpretation that garnet fractionates Sr, Y, and REE, high Sr/Y and La/Yb could be also produced by multiple ways such as inheriting the source features and fractional crystallizing clinopyroxene (cpx). Therefore, it may be problematic using high Sr/Y and La/Yb as criteria to identify adakites. Ins

关键词： C型埃达克岩镁铁质下地壳部分熔融基性岩高温高压实验 SiO2含量成因高温高压条件

Remelting of subducted continental lithosphere: Petrogenesis of Mesozoic magmatic rocks in the Dabie-Sulu orogenic belt

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Science China Earth Sciences 2009年第7期52卷 1295-1318页

作者： ZHAO ZiFu ZHENG YongFei CAS key laboratory of Crust-Mantle materials and environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

The Dabie-Sulu orogenic belt was formed by the Triassic continental collision between the South China Block and the North China Block. There is a large area of Mesozoic magmatic rocks along this orogenic belt, with emplacement ages mainly at Late Triassic, Late Jurassic and Early Cretaceous. The Late Triassic alkaline rocks and the Late Jurassic granitoids only crop out in the eastern part of the Sulu orogen, whereas the Early Cretaceous magmatic rocks occur as massive granitoids, sporadic intermedi- ate-mafic intrusive and volcanic rocks throughout the Dabie-Sulu orogenic belt. Despite the different ages for their emplacement, the Mesozoic magmatic rocks are all characterized not only by enrichment of LREE and LILE but depletion of HFSE, but also by high initial Sr isotope ratios, low εNd(t) values and low radiogeneic Pb isotope compositions. Some zircons from the Jurassic and Cretaceous granitoids contain inherited magmatic cores with Neoprotozoic and Triassic U-Pb ages. Most of the Cretaceous mafic rocks have zircon δ18O values and whole-rock δ13C values lower than those for the normal mantle. A systematic comparison with adjacent UHP metaigneous rocks shows that the Mesozoic granitoids and mafic rocks have elemental and isotopic features similar to the UHP metagranite and metabasite, respectively. This indicates that these magmatic and metamorphic rocks share the diagnostic features of lithospheric source that has tectonic affinity to the northern edge of the South China Block. Their precursors underwent the UHP metamorphism and the post-collisional anatexis, respectively at different times and depths. Therefore, the Mesozoic magmatic rocks were derived from anatexis of the subducted continental lithosphere itself beneath the collision-thickened orogen; the geodynamic mechanism of the post-collisional magmatisms is tectonic collapse of orogenic roots in response to lithospheric extension.

关键词： continental subduction lithosphere anatexis post-collisional magmatism Mesozoic tectonics UHP metamorphic rocks Dabie-Sulu

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Introduction to advances in the study of supercritical geofluids

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Science China Earth Sciences 2023年第10期66卷 2391-2394页

作者： Huaiwei NI School of Earth and space Sciences University of Science and Technology of ChinaHefei230026China key laboratory of Crust-Mantle materials and environments&Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei230026China

The role of supercritical geofluids has received increasing attention in frontier research of geological processes in the deep Earth(Ni,2020).Supercritical geofluids(hereafter referred to as supercritical fluids)are a special type of fluids permitted by complete miscibility between rock components(e.g.,silicates,carbonates,and sulfates)and water under high conditions of temperature and pressure.

关键词： fluids hereafter frontier