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Acta Geologica Sinica(English Edition) 2023年第2期97卷 623-635页

作者： ZHAO Zhenming ji wenhua FU Chaofeng Xi'an Center China Geological SurveyXi'an 710054China Key Laboratory of Western Mineral Resources and Geological Engineering Ministry of Education of China and Chang'an UniversityXi'an 710054China State Key Laboratory of Loess and Quaternary Geology Institute of Earth and EnvironmentCASXi'an 710075China

The Tibetan Plateau is an important area for studying global climate change,but the answers to many scientific problems remain ***,we present new information from the lacustrine sedimentary record in the western Tibetan Plateau,related to the third most-recent *** sediment data,including sporopollen,particle size,total organic carbon,mass susceptibility,CaCO_(3),CaSO_(4),BaSO_(4)contents and chronological data,were reconstructed and revealed that climate and environmental conditions obviously and distinctly changed between 600 and 700 thousand years *** comparison,the data obtained from the Guliya ice core in this area also corresponds to the global glacial climatic characteristics recorded in basin sediments in the eastern and southeastern regions of the plateau and to the information obtained from ice cores in the Antarctic and Arctic *** this study,we conclude that the main reason for the glaciations and new tectonic movement must be a geomagnetic polarity reversal 774 thousand years ago(from Matuyama to Brunhes).Indeed,the results of this study suggest that the described reversal event might have influenced the current global climate pattern and will continue to impact climatic changes in the future.

关键词： glacial record global climate change geomagnetic polarity reversal middle Pleistocene western Tibetan Plateau

Oxidative coupling of methane in a dual-bed reactor comprising of particle/cordierite monolithic catalysts

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Journal of Natural Gas Chemistry 2010年第6期19卷 600-604页

作者： Deng Pan Shengfu ji wenhua Wang Chengyue Li State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijng 100029 China

A dual-bed reactor was constructed comprising of a 5%Na2WO4-2%Mn/SiO2 particle catalyst and a 4%Ce-5%Na2WO4-2%Mn/SiO2 /cordierite monolithic *** reaction performance of the oxidative coupling of methane （OCM） over the dual-bed reactor system was *** effects of the bed height and operation mode,as well as the reaction parameters such as reaction temperature,CH4/O2 ratio and flowrate of feed gas,on the catalytic performance were *** results indicated that the suggested dual-bed reactor exhibited a good performance for the OCM reaction when the feed gases firstly passed through the particle catalyst bed and then to the monolithic catalyst bed.A CH4 conversion of 38.2% and a C2H4 selectivity of 43.3% could be obtained using the dual-bed reactor with a particle catalyst bed height of 10 mm and a monolithic catalyst bed height of 50 *** the CH4 conversion and C2H4 selectivity have increased by 2.5% and 12.8%,respectively,as compared with the 5%Na2WO4-2%Mn/SiO2 particle catalyst in a conventional single-bed reactor and by 12.9% and 23.0%,respectively,as compared with the 4%Ce-5%Na2WO4-2%Mn/SiO2 /cordierite monolithic catalyst in a single-bed *** catalytic performance of the OCM in the dual-bed reactor system has been improved remarkably.

关键词： oxidative coupling of methane dual-bed reactor monolithic catalysts

An Early Aged Ophiolite in the Western Kunlun Mts., NW Tibetan Plateau and Its Tectonic Implications

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Acta Geologica Sinica(English Edition) 2005年第6期79卷 778-786页

作者： XIAO Xuchang WANG Jun SU Li ji wenhua SONG Shuguang Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 Geological Lab Center China University of Geosciences （Beijing） Beijing 100083 Xi＇an Institute of Geology Xi＇an Shanxi 710054 School of Earth and Space Sciences Peking University Beijing 100087

The early aged ophiolites have attracted attention of many geologists in recent decades, because the early aged ophiolites can provide the information about the ancient oceanic processes relevant to the evolution of plate tectonics in the early period of the earth, and also concern such problems as whether there existed a ＂Proto-Tethys＂ and the break-up and convergence of the Rodinian Supercontinent. This paper reveals a definite complete ophiolite of Neoproterozoic-Early Paleozoic, named Kuda ophiolite in the western Kunlun Mrs., NW Tibetan Plateau, and reports the recent reasonable SHRIMP zircon U-Pb ages of 510±4 Ma, and 502±13 Ma for the cumulates of the Kuda ophiolite, using the most powerful dating tool, the SHRIMP-Ⅱ. The geochemical and geochronology data integrating with the geological setting suggest that the Kuda ophiolite might have formed in an archipelago oceanic basin, not in a vast ocean, the so-called ＂Proto-Tethys＂, and was tectonically emplaced during the Early Paleozoic.

关键词： Kuda ophiolite western Kunlun Mts. SHRIMP U-Pb isotopic dating tectonics Neoproterozoic Early Paleozoic

Efficiency and Economy of a New Agricultural Rainwater Harvesting System

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Chinese Journal of Population,Resources and Environment 2010年第4期8卷 41-48页

作者： ji wenhua Cai jianming Marinus van Veenhuizen Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Graduate University of Chinese Academy of Sciences Beijing 100049China ETC-Urban Agriculture Leusden 3830 ABNetherland

Shortage of water is the key limiting factor for agricultural development of *** harvesting(RWH) could provide an alternative water source for greenhouse agriculture,but local natural and socioeconomic conditions challenge the application of the *** article analyses the advantages and disadvantages of different types of greenhouse RWH in Beijing,and describes a new greenhouse RWH system demonstrated in 2008 in Huairou,a suburb district of *** analyses the efficiency,cost-benefit ratios and limiting factors of the new *** results show that with the new system,RWH efficiency can be as high as 66%(of total rainfall) and the rainwater usage rate can reach 69% of total water *** ratio of benefit to cost of government investment can be 1.84,and the ratio of benefit to cost of a farmer's investment could be 1.68 provided the project is designed to save water and also increase ***,the price of groundwater for agriculture directly influences the potential for applying and scaling up the *** the RWH system does not increase the farmers' incomes at the current water price,they will not use it until the water price rises to a critical point,which is determined by external *** article also suggests a number of measures to increase the efficiency of the system in order to apply it on a large scale.

关键词： Beijing greenhouse agriculture rainwater harvesting cost-benefit

Mapping uncovered a multi-phase arc-back-arc system in the southern Beishan during the Permian

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National Science Review 2023年第2期10卷 14-16页

作者： Tong Hong Gabriel S.Santos Cees R.van Staal wenhua ji Shoufa Lin Department of Earth and Environmental Sciences University of Waterloo Geological Survey of Canada China Geological Survey Xi'an Centre School of Resources and Environmental Engineering Hefei University of Technology

The Central Asian orogenic belt(CAOB),surrounded by the Baltica and Siberia cratons to the north,and the Tarim and North China cratons to the south,records successive evolution cycles of subduction and accretion/collision from Neoproterozoic to the Paleozoic that consumed and eventually closed the Paleo-Asian Ocean[1].Tectonic models of the terminal orogenesis are contentious,with discussions ranging from the time and location of final closure of the Paleo-Asian Ocean to the regional context and setting of its various tectonic constituents.

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Late Carboniferous-Early Permian Mafic-Ultramafic Complexes in Beishan,Southwestern Central Asian Orogenic Belt and Their Significance

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Acta Geologica Sinica(English Edition) 2019年第S1期93卷 113-115页

作者： KANG Lei ji wenhua WANG Tao LI Wenming SUN jiming 无 Department of Geology Northwest UniversityXi'an 710069China Key Laboratory for the Study of Focused Magmatism and Giant Ore Deposits MLRCentre of Orogenic Belt GeologyCGSCenter of Geological SurveyCGSXi'an 710054China Key Laboratory of Deep-Earth Dynamics Ministry of Natural ResourcesInstitute of GeologyChinese Academy of Geological SciencesBejing 100037China Xi’an Institute of Geological and Mineral exploration Xi'an 710100China

Numeral Permian mafic-ultramafic complexes occur in the Beishan terrane atthe northeastern margin of the Tarim craton,southwestern Central Asian Orogenic Belt,including the Pobei,Cantoushan,Bijiashan,Hongshishan,Xuanwoling,Zhongposhan and Luodong etc.,intrusions(Qin et al.,2011;Zhang et al.,2017;Xue et al.,2018).These Beishan mafic-ultramafic complexes are composed of peridotite,pyroxenite.

关键词： Late Carboniferous-Early Permian Mafic-ultramafic Complexes Beishan Tarim Large Igneous Province

The discovery of Palaeoproterozoic volcanic rocks in the Bulunkuoler Group from the Tianshuihai Massif in Xinjiang of Northwest China and its geological significance

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Science China Earth Sciences 2011年第1期54卷 61-72页

作者： ji wenhua LI RongShe CHEN Shoujian HE ShiPing ZHAO ZhenMing BIAN XiaoWei ZHU HaiPing CUI jiGang REN JuanGang Xi'an Institute of Geology and Mineral Resource Xi'an 710054 China Shaanxi Institute of Geological Survey Xianyang 712000 China

In the Dabudaer region of the Tianshuihai Massif （Xinjiang, Northwest China）, metavolcanic rocks within the mainly meta- sedimentary Bulunkuoler Group are basalt, basaltic andesite, and rhyolite. In situ zircon U-Pb LA-ICP-MS dating on rhyolite magmatic zircons yielded an age of 2481±14 Ma, interpreted as the eruption age of the Bulunkuoler Group volcanic rocks. The basalt and basaltic andesite are low-A1 tholeiite series and the rhyolite is low-Al calc-alkaline series. All of rocks are charac- terized by enrichment of LREE and LILE （Rb, Th and Ba）, depletion of P, Nb, Ta and Ti, and absence of Eu anomalies. The Cnd（t） of basalts ranges from 3.14 to 4.88 indicating a depleted mantle source. The trace element signatures show that these magmas experienced intense crustal contamination during their ascent. Direct evidence for crustal contamination is the xenocrystic zircons in the ryholite, with ages back to ca. 3300 Ma. The primitive-mantle normalized and Zr/Y-Zr diagrams for the basic volcanic rocks show that they formed in an intra-continental tectonic setting. Combined with the previous studies and compared with North China Craton Neoarchean basic volcanic rocks, it is supposed that the Bulunkuoler Group volcanic rocks reflect the Palaeoproterozoic mantle magma underplating and interaction with felsic crust.

关键词： Karakorum Bulunkuoler Group zircon LA-ICP-MS U-Pb dating tholeiite underplating

Discovery of ～4.0 Ga detrital zircons in the Changdu Block,North Qiangtang,Tibetan Plateau

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Chinese Science Bulletin 2011年第7期56卷 647-658页

作者： ShiPing He RongShe Li Chao Wang HongFei Zhang wenhua ji PuSheng Yu PingYang Gu Chao Shi Xi’an Institute of Geology and Mineral Resources Xi’an China Faculty of Earth Science China University of Geosciences Wuhan China

在 situ 锆石由 LA-ICP-MS 和 MC-ICP-MS 标明日期使用， 3981 的由岩屑形成的锆石 ??? 鮼铧?? ? 裦蒚铩 ????? 偃 ?? 鮼 ?? 郥趽 ????腘吗？？

关键词：碎屑锆石遗传算法北羌塘昌都高原地壳物质喜马拉雅地区羌塘地区

A tale of elemental accumulation and recycling in the metamorphosed Keketale VMS-type Pb-Zn deposit,Altai Mountains

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Geoscience Frontiers 2023年第1期14卷 247-271页

作者： Chao Sun Huishan Zhang Xiaoyong Yang wenhua ji Bo Chen Yanguang Li Zengchan Dong Mohamed Faisal Mengqi jin Xiaojian Zhao CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology University of Science and Technology of ChinaHefei 230026China MNR Key Laboratory for the Study of Focused Magmatism and Giant Ore Deposits Xi'an Center of Geological SurveyCGSXi'an 710054China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Chengdu Center of Geological Survey CGSChengdu 610081China Department of Geology Faculty of ScienceSuez Canal UniversityEl-Ismailia 41522Egypt

The elemental accumulation and recycling in the metamorphosed Keketale VMS-type Pb-Zn deposit of the Altai Mountains are presented in this *** on detailed fieldwork and microscopic observation,the formation of the deposit involved syngenetic massive sulfide mineralization and epigenetic superim-posed *** generations of iron sulfides(i.e.,pyrite and pyrrhotite)with contrasting textural,elemental,and sulfur isotopic features were generated in primary mineralization(including hydrothermal iron sulfides,colloform pyrite)and secondary modification(including annealed iron sul-fides,oriented iron sulfides,and vein-pyrite).It is revealed that the spatial variation in textures and ele-ments of hydrothermal iron sulfides depends on the inhomogeneous fluid compositions and varied environment in VMS hydrothermal *** leached sulfur from the footwall volcanic rocks and reduced sulfur by the TSR process are regarded as important sulfur ***,large sulfur iso-topic fractionation and negativeδ^(34)S values were mainly caused by varied oxygen fugacity,and to a lesser extent,temperature *** epigenetic polymetallic veins that contain sulfides and sulfosalts(e.g.,jordanite-geocronite,bournonite-seligmannite,boulangerite)were considered as the products of metamorphic fluid scavenged the metal-rich *** things considered,it is indicated that two epi-sodes of fluid with distinct origins were essential for the formation of the *** predominant evolved seawater along with subordinate magmatic fluid mobilized metals from volcanic rocks and pre-cipitated massive sulfides near the seafloor are vital for primary *** metamorphic fluid remobilized metals(i.e.,FMEs:fluid mobile elements,e.g.,Pb,As,Sb)from neighboring volcanic and pyroclastic rocks and destabilized them within the fractured zone are responsible for secondary miner-alization,which enhances the economic value of the ***,metal-ric

关键词： Pyrite Trace element Sulfur isotope Keketale Pb-Zn deposit VMS deposit Altai Mountains

Amino-modified COFs as SPE adsorbent for determination of carboxylic acid pesticides

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Amino-modified COFs as SPE adsorbent for determination of ca...