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Discovery of Cu-Zn,Cu-Sn intermetallic minerals and its significance for genesis of the Mianning-Dechang REE Metallogenic Belt,Sichuan Province,China

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Science China Earth Sciences 2006年第6期49卷 597-603页

作者： XIE Yuling1, HOU Zengqian2, XU Jiuhua1, YUAN Zhongxin2, BAI Ge2 & LI Xiaoyu3 1. Civil and Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083, China 2. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 3. The 109th Geological Team, Sichuan Bureau of Mineral Exploration, Chengdu 610100, China Civil and Environmental Engineering School University of Science and Technology Beijing Beijing China Institute of Geology Chinese Academy of Geological Sciences Beijing China The 109th Geological Team Sichuan Bureau of Mineral Exploration Chengdu China

Mianning-Dechang Himalayan REE Metallogenetic Belt in Sichuan Province lies along the western margin of the Yangtze Craton. We have conducted detailed mineralogical studies on ore minerals collected from Maoniuping and Dalucao, the two largest deposits in the belt. With optical microscope, SEM/EDS, and EPMA, three rare intermetallic minerals, i.e., zinccopperite (Cu2Zn), Sn- bearing native copper, and Cu-bearing jupiter were found to occur in the main ore along with barite, fluorite, apatite, sulfide and bastnaesite. Since the conditions under which zinccopperite and Sn- bearing native copper formed are quite unique, finding of these minerals, for the first time in domestic REE deposits, has significant implications for the genesis of the ore deposits in which they occur. In comparison with Cu-Zn intermetallic minerals in other occurrences, we propose that the formation of this REE metallogenetic belt is associated with fast upwelling of the Himalayan magma from deep source.

关键词： Mianning-Dechang REE metallogenetic belt, Cu-bearing intermetallic minerals, EPMA, genesis significance, deep source magmatic activity.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,China

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Science China Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2, TAO Mingxin2,3 & YE Xianren2 1. Resources and Environmental School, Lanzhou University, Lanzhou 730000, China 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of Sciences, Lanzhou 730000, China 3. College of Resources Science & Technology, Beijing Normal University, Beijing 100875, China Resources and Environmental School Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China College of Resources Science & Technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, China, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternChina; ratios of ~3He/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3He from 2.5 x 10~9 to 27 x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Clay mineral records of East Asian monsoon evolution during late Quaternary in the southern South China Sea

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Science China Earth Sciences 2005年第1期48卷 84-92页

作者： C.Colin A.Trentesaux D.Blamart FRE 2566 Orsaylerre UMR PBDS du CNRSLaboratoire des Sciences du Climat et de I'Environnement Université de Paris XI91405 OrsayFranceUniversite de Lille I59655 Villeneuve d'AscqFranceLaboratoire mixte CNRS-CEA91198 Gif-sur-YvetteFrance

High-resolution clay mineral records combined with oxygen isotopic stratigraphy over the past 190 ka during late Quaternary from core MD01-2393 off the Mekong River in the southern South China Sea are reported to reconstruct a history of East Asian monsoon *** dominating clay mineral components indicate a strong glacial-interglacial cyclicity, with high glacial illite, chlorite, and kaolinite contents and high interglacial smectites content. The provenance analysis indicates the direct input of clay minerals via the Mekong River drainage *** and chlorite derived mainly from the upper reach of the Mekong River, where physical erosion of meta-sedimentary rocks is dominant. Kaolinite derived mainly from active erosion of inhered clays from reworked sediments in the middle reaches. Smectites originated mainly through bisiallitic soils in the middle to lower reaches of the Mekong River. The smectites/(illite+chlorite)and smectites/kaolinite ratios are determined as mineralogical indicators of East Asian monsoon variations. Relatively high ratios occur during interglacials and indicate strengthened summer-monsoon rainfall and weakened winter-monsoon winds; relatively lower ratios happened in glacials, indicating intensified winter monsoon and weakened summer monsoon. The evolution of the summer and winter monsoons provides an almost linear response to the summer insolation of the Northern Hemisphere, implying an astronomical forcing of the East Asian monsoon evolution.

关键词： clay minerals, East Asian monsoon, late Quaternary, Mekong River, South China Sea.

Magnetic mineral diagenesis in the post-glacial muddy sediments from the southeastern South Yellow Sea:Response to marine environmental changes

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Science China Earth Sciences 2005年第1期48卷 134-144页

作者： Jeong-Hae Chang Korean Institute of Geology

Core YSDP103 was retrieved in the muddy deposit under the cold eddy of the southeastern South Yellow Sea, and the uppermost 29.79 m core represents the muddy sediments formed in the shelf since about 13 ka BP. The lower part from 29.79 to 13.35 m, called Unit A2, was deposited during the period from the post-glacial transgression to the middle Holocene (at about 6 14C ka BP) when the rising sea level reached its maximum, while the upper part above 13.35 m (called Unit A1) was deposited in a cold eddy associated with the formation of the Yellow Sea Warm Current just after the peak of post-glacial sea level rise. Rock-magnetic properties of the uppermost 29.79 m core were investigated in detail. The experimental results indicate that the magnetic mineralogy of the core is dominated by magnetite, maghemite and hematite and that, except for the uppermost 2.35 m, the magnetic minerals were subject to reductive diagenesis leading to significant decline of magnetic mineral content and the proportion of low-coercivity component. More importantly, ferrimagnetic iron sulphide (greigite) is found in Unit A2 but absent in Unit A1, suggesting the control of marine environmental conditions on the magnetic mineral diagenesis. Magnetic parameters show abrupt changes across the boundary between Units A1and A2, which reflects a co-effect of environmental conditions and primary magnetic components of the sediments on the diagenesis. Alternating zones of high and low magnetic parameters are observed in Unit A2, which is presumably due to periodic changes of the concentration and/or grain size of magnetic minerals carried into the study area.

关键词： environmental magnetism, magnetic minerals, diagenesis, ferrimagnetic iron sulphide, South Yellow Sea.

Geochemical research on C-O and Sr-Nd isotopes of mantle-derived rocks from Shandong Province, China

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Science China Earth Sciences 2004年第2期47卷 171-180页

作者： LIU Jianming, ZHANG Hongfu, SUN Jinggui & YE Jie1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. School of Earth Science, Jilin University, Changchun 130061, China Correspondence should be addressed to Liu Jianming (email: jmliu@***) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China School of Earth Science Jilin University Changchun China

This paper presents systematic studies on the C-O and Sr-Nd isotopic compositions for Cretaceous Badou carbonatites, Fangcheng basalts, and Jiaodong lamprophyres and Paleozoic Mengyin kimberlites in Shandong Province, China. Paleozoic kimberlites have normal and uniform C-O isotopic compositions with δ13C and δ18O in the range of -4.8‰--7.6‰ and +9.9‰-+13.2‰, respectively. However, Cretaceous three different types of mantle-derived rocks have quite different C-O isotopic compositions, indicating that the mantle sources are probably partially contaminated with organic carbon-bearing crustal materials. These Cretaceous rocks show uniform and EMII-like Sr-Nd isotopic compositions and also indicate that the mantle sources were affected by recycled crustal materials. Comparative studies of C-O and Sr-Nd isotopes reveal that the lithospheric mantle beneath the eastern North China Craton had different isotope characteristics in the Paleozoic, the early Cretaceous, and the Tertiary time. This demonstrates that the lithospheric mantle beneath the region underwent at least twice reconstructions since the Paleozoic. Available data imply that the first reconstruction mainly happened during the Triassic-Jurassic time with gradual changes and the second in the Cretaceous with abrupt changes. Results also show that the early Cretaceous (especially at 120-130 Ma) was perhaps the key period leading to the dramatic change of the Mesozoic geodynamics on the eastern North China Craton.

关键词： mantle-derived rocks, carbonate minerals, C-O isotope, Sr-Nd isotope, lithospheric mantle, Shandong.

Quaternary clay mineralogy in the northern South China Sea (ODP Site 1146) —— Implications for oceanic current transport and East Asian monsoon evolution

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Science China Earth Sciences 2003年第12期46卷 1223-1235页

作者：刘志飞 Alain Trentesaux Steven C.Clemens 汪品先 Laboratory of Marine Geology Tongji University Shanghai 200092 China UMR PBDS du CNRS Universit?des Sciences et Technologies de Lille 59655 Villeneuve d'Ascq France Department of Geological Sciences Brown University Providence RI 02912 USA

Measurement of clay mineralogy at ODP Site 1146 in the northern South China Sea (SCS) indicates that illite, chlorite, and kaolinite contents increased during glacials and smectite content increased during interglacials. The smectite/(illite+chlorite) ratio and the smectite abundance were determined as mineralogical indicators for the East Asian monsoon evolution. At a 10 ka timescale, prevailing southeasterly surface oceanic currents during interglacials transported more smectite from the south and east areas to the north, showing a strengthened summer monsoon circulation, whereas dominated counter-clockwise surface currents during glacials carried more illite and chlorite from Taiwan as well as from the Yangtze River via the Luzon Strait to the northern SCS, indicating a strongly intensified winter monsoon. Based on a 100 ka timescale, a linear correlation between the smectite/(illite+chlorite) ratio and the sedimentation rate reflects that the winter monsoon has prevailed in the northern SCS in the intervals 2000—1200 ka and 400—0 ka and the summer monsoon did the same in the interval 1200—400 ka. The evolution of the summer monsoon provides an almost linear response to the summer insolation of Northern Hemisphere, implying an astronomical forcing of the East Asian monsoon evolution.

关键词： clay minerals, sedimentation rate, East Asian monsoon, Quaternary, South China Sea.

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Global glance

China Rare Earth Information 2017年第4期23卷 6-8页

Queensland could likely play host to a number of rare minerals, as geologists have unearthed evidence suggesting the presence of platinum and gold, as well as rare-earth elements (REE). "This may be a whole new frontier for Queensland," Natural Resources and Mines Minister Dr Anthony Lynham said over the weekend. "Beyond the potential economic boost for Queensland, the discovery brings a new understanding of mineral potential in a previously under-explored area."

关键词： Queensland could likely play host to a number of rare minerals, as geologists have unearthed evidence suggesting the presence of platinum and gold, as well as rare-earth elements (REE).

Instructions for Authors

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International Journal of minerals,Metallurgy and Materials 2017年第6期24卷 726-726页

International Journal of minerals, Metallurgy and Materials is dedicated to the publication and the dissemination of original research articles (and occasional invited reviews) in the fields of minerals, Metallurgy and Materials. It is covered by EI Compendex, SCI Expanded, Chemical Abstract, etc. The following components are required for a complete manuscript: Title, Author(s), Author affiliation(s), Abstract, Keywords,Main text, Acknowledgements and References.

关键词： International Journal of minerals, Metallurgy and Materials is dedicated to the publication and the dissemination of original research articles (and occasional invited reviews) in the fields of minerals, Metallurgy and Material