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Characteristics and origin of mafic and ultramafic xenoliths in trachyandesite lavas from Heikongshan volcano,Tengchong,Yunnan province,china

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Science china Earth Sciences 2010年第9期53卷 1295-1306页

作者： YU HongMei, LIN ChuanYong, SHI LanBin, XU JianDong & CHEN XiaoDe Institute of Geology, china Earthquake Administration, Beijing 100029, china 1. Institute of Geology China Earthquake Administration Beijing 100029 China

The trachyandesite lavas from Heikongshan volcano of the Tengchong volcanic cluster, Yunnan province contain relatively abundant mafic and ultramafic small xenoliths comprising mainly gabbro, pyroxenite and rare lherzolites, all less than 2.5 cm in size. Gabbro xenoliths are characterized by "open" texture represented by relatively abundant vesicles and ground-mass fillings, while pyroxenite xenoliths are characterized by equigranular and poikilitic texture. Their mineral compositions (clinopyroxene ± orthopyroxene ± plagioclase) are similar to those of phenocrysts in lavas, and their equilibration temperature (1000-1125°C) is consistent with the crystallization temperature of the phenocrysts (998-1108°C). Thus, the textures and compositions of these xenoliths are different from those of lower crustal and mantle xenoliths, and were derived from the magma chamber. Among them, the gabbroic xenoliths come from the crystal-bubble-liquid zone at the top of the magma reservoir, while the pyroxenite xenoliths come from the cumulates in the bottom of magma reservoir. The studied single lherzolite xenolith with porphyroclastic texture has similar mineral compositions to the mantle xenoliths from eastern china, and is considered to be of upper mantle origin. It was brought into magma reservoir by replenishment magma, and might have experienced a cooling event before eruption. The formation of xenoliths in trachyandesite flows largely reflects the ascent, storage, evolution and eruption processes of magma.

关键词： magma chamber xenoliths geothermo-barometry trachyandesite Heikongshan volcano Tengchong

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progress in researching into the transition of the Mesozoic tectonic systems in southeast china

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progress in Natural Science:Materials International 2006年第6期16卷 563-572页

作者： YU Xinqi, WU Ganguo, ZHANG Da, ZHANG Xiangxin, DI Yongjun, ZANG Wenshuan, WANG Qunfeng and HUANG Huojian (State key Laboratory of Geological processes and Mineral Resources, china University of Geosciences, Beijing 100083, china key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, china University of Geosciences, Beijing 100083, china) [a] State key Laboratory of Geological processes and Mineral Resources Chine University of Geosciences Beijing China [b] key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing China

This paper presents the latest progress made on the research of Mesozoic tectonic system transition from the E-W paleo-Tethyan tectonic domain into NE-NNE western pacific domain in southeast china. Tectonism of the west pacific domain began at middle Jurassic (J2) and formed a set of NE-trending structures, non-coaxially overprinting on E-trending tectonic belts which may be early and coevally produced by the paleo-Tethyan domain. Thus began the tectonic domain transition from the E-trending paleo-Tethyan to the NE-trending pacific and fully finished at the early Cretaceous. The eastern Nanling area was a junction zone of the transition at middle Jurassic (J2),and ever since the junction zone might obliquely migrate to the coastal region, where is the east part of this study area. To the north of the Nanling area, the Ganjiang Fault Zone was the boundary between two tectonic domains. Corresponding to the transition of tectonic system, the geodynamics of SE china changed from a compressional system to an extensional system, which continued until the end of Mesozoic-Tertiary.

关键词： transition of tectonic system non-coaxial overprint obliquely migrate Mesozoic paleo-Tethyan tectonic domain west pacific tectonic domain southeast china.

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National guidelines for diagnosis and treatment of colorectal cancer 2020 in china(English version)

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Chinese Journal of Cancer Research 2020年第4期32卷 415-445页

作者： National Health Commission Of The people's Republic Of china National Health Commission of the people's Republic of china

*** 2.1 Clinical manifestations 2.2 Disease history and family history 2.3 physical examination 2.4 Clinical laboratory examinations 2.5 Endoscopy 2.6 Imaging 2.6.1 Common testing 2.6.2 Imaging evaluation of clinical crucial issues in colon cancer 2.6.3 Imaging evaluation of clinical crucial issues in rectal cancer 2.6.4 MRI structural report of rectal cancer is recommended 2.6.5 CT structural report of colon cancer can be used 2.7 Histopathological examination 2.8 Open surgery or laparoscopic exploration.

关键词： diagnosis colon cancer

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Metallogenic epoch and genesis of the gold deposits in Jiaodong peninsula, Eastern china: a regional review

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progress in Natural Science:Materials International 2007年第2期17卷 138-143页

作者： YANG Liqiang, DENG Jun, GE Liangsheng, WANG Qingfei, ZHANG Jing, GAO Bangfei, JIANG Shaoqing and XU Hao ( State key Laboratory of Geological processes and Mineral Resources, china University of Geosciences, Beijing 100083, china key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, china University of Geosciences, Beijing 100083, china) [a]State key Laboratory of Geological processes and Mineral Resources China University of Geosciences Beijing China [b]key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing China

Gold deposits are characterized by multi-sources, superimposition, large scale and temporal-spatial concentration in Jiaodong peninsula, Eastern china. In this paper, we review the history and the development of the study on metallogenic chronology and genesis of gold deposits, summarize the main features of superimposed metallogenesis, provide evidence of the Mesozoic complex metallogenic system, and point out some problems for further research of Jiaodong gold deposit cluster from a regional view. Although gold deposits are different in genetic types, ore-forming materials and geological settings, our research indicates that the accumulation and emplacement of the ore-forming materials are temporally-spatially concentrated on a large scale, and the main metallogenic epoch of Jiaodong gold deposits was concentrated in Mesozoic. Metallogenic chronology and geological-geochemical data indicate that there are two periods of gold mineralizations occurred in 130-110 Ma and 90-80 Ma respectively in Jiaodong ore cluster. The gold deposit cluster results from the superimposition of the polygenetic mineralization, and further study is needed to investigate the formation and evolution of the Mesozoic complex metallogenic system.

关键词： superimposed metallogenic system Mesozoic Jiaodong ore cluster.

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Composition of sandstone and heavy minerals implies the provenance of kuqa Depression in Jurassic, Tarim basin, china

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progress in Natural Science:Materials International 2005年第7期15卷 633-640页

作者： WU Chaodong, LIN Changsong, SHEN Yanping and FENG Xue ( key Laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education, p.king University, Beijing 100871, china Department of Resources, china University of Geosciences, Beijing 100083, china) key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education Peking University Beijing 100871 China. Department of Resources China University of Geosciences Beijing 100083 China

The petrological characteristics and heavy mineral assembly of the Jurassic System in kuqa Basin are consistent with the tectonic evolution, which is the major factor controlling the filling process of kuqa Basin. Controlled by the source areas at the both sides of the Basin, the matrixes are dominated by sedimentary rock, high-grade metamorphic rock, acid magmatic rock, and the highest heavy mineral assemblage of zircon-garnet-magnetite in the content. According to heavy mineral indexes, the Jurassic strata can be classified into three rhythmic units of heavy mineral. The lower sequence contains abundant heavy minerals and relatively high content of detritus and its matrixes primarily came form the recycling orogen. The assemblage of "zircon-garnet-magnetite" indicates that the sedimentary area in the early evolution period of the basin is relatively near the provenance. The middle sequence is different from the lower sequence in the heavy mineral assemblage and has the different characteristics from that of source rock. The heavy mineral assemblage is "garnet-zircon" with the highest content of garnet and its main matrices are the high-grade metamorphic rock, acid magmatic rock and hydrothermal vein at the northeastern edge of the basin. The middle and upper sequences are characterized by the clast provenance, which is primarily from the recycling orogen at the northern edge of the basin and secondarily from the southern uplift. As a result of the two provenances, the strata with apparent changes of heavy mineral assemblage and index better coincides with the interfaces of the secondary strata sequences, which reflects the denudation history and the filling process of the orogen at the northern edge of the basin.

关键词： sandstone components provenance analysis filling sequence tectonic evolution.

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Mesozoic subduction-accretion zone in northeastern South china Sea inferred from geophysical interpretations

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Science china Earth Sciences 2006年第5期49卷 471-482页

作者： ZHOU Di1, WANG Wanyin2, WANG Jialin3, pANG Xiong4, CAI Dongsheng5 & SUN Zhen1 1. key Laboratory of Marginal Sea Geology, South china Sea Institute of Oceanology, Chinese Academy of Sciences, Guang- zhou 510301, china 2. College of Geological and Topographical Engineering, Chang’an University, Xi’an 710054, china 3. key Laboratory of Marine Geology, Tongji University, Shanghai 200092, china 4. china National Offshore Oil Co. Limited – Shenzhen Branch, Shenzhen 518067, china 5. china National Offshore Oil Co. Limited – Research Center, Beijing 100027, china 1. key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. College of Geological and Topographical Engineering Chang’an University Xi’an 710054 China 3. key Laboratory of Marine Geology Tongji University Shanghai 200092 China 4. china National Offshore Oil Co. Limited — Shenzhen Branch Shenzhen 518067 China 5. china National Offshore Oil Co. Limited — Research Center Beijing 100027 China

A segment of Mesozoic subduction-accretion zone was inferred across thenortheastern South china Sea at approximately NE450 orientation. Basic evidence includes thefollowing: A belt of peek gross horizontal Bouguer gravity gradient (pGHGBA) is comparable in sizeand intensity to that of the Manila subduction-accretion zone. A belt of high positive magneticanomalies appears to the north and sub-parallel to the pGHGBA, representing the volcanic arcassociated to the subduction zone. The pGHGBA crosses obliquely both Cenozoic structures and presentseafloor topography, indicating a pre-Cenozoic age. The segment is offset left-laterally byNW-running strike-slip faults, in concord with the Mesozoic stress field of South china. Inaddition, the existence of the subduction zone is supported by wide-angle seismic data obtained indifferent years by different institutions. At approximate localities, a north-dipping ramp of Mohosurface is indicated by records of ocean-bottom seismometers, and a strong reflector about 8 kmbeneath the Moho reflector is indicated by both OBS and long-cable seismic records. Theidentification of a segment of Mesozoic subduction zone in NE South china Sea fills nicely the gapof the Great Late Mesozoic Circum SE Asia Subduction-acrretion Zone, which extended from Sumatra,Java, SE kalimantan to N palawan, and from Taiwan, Ryukyu to SW Japan.

关键词： Mesozoic, subduction zone, SE Asia, NE South china Sea, geophysics.

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RAISING SIBERIAN TIGERS IN CApTIVTTY IN NORTHEAST china

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Journal of Northeast Forestry University 1990年第1期1卷 72-78页

作者： Liu XinchenBreeding Center of Fetidac Animals. Hcr.gdaohczi. Heilongjiang province. p R china 1. Breeding Center of Fetidae Animals Hengdaohezi Heilongjiang Province P. R. China

The Breeding Center of Felidac Animals was founded in *** in *** paper resents the methods and observauons of practices in feeding,mating,breeding,study and management of a captive population of siberian tigers at the *** the es-tablishment of the program,the initial population of 5 males and 15 females has been increased to *** the past 3 years.37 cubs were born and 28 *** averagc litter size was 2.6 in 1988and 2.8 in *** of feeding mating and raising are continualluy modified according to obser-vations,experimental comparisons and program *** program templ to conserve and renaturalize this rare and preeious species.

关键词： Endangered species. Siberian tiger. Species conservation

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Clinopyroxenes in kimberlites of china

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 259-270页

作者： Dong Zhenxin Geological Museum of china, Beijing Fei Zhenbi Geological Museum of china Beijing

The author studied the grain size, shape, colour, altered coat, mineral species, chemical composition,end- member components and infrared spectra of clinopyroxenes occurring as megacryst, macrocryst andgroundmass minerals, intergrowths with pyrope and ilmenite and minerals in deep-seated xenoliths and inclu-sions in diamonds in kimberlites of china. The clinopyroxenes under study were compared with megacrystclinopyroxenes in basalts and minerals in their deep-seated xenoliths and clinopyroxenes in lamproites andminettes. The coexisting clinopyroxene-pyrope pair was studied. Besides the author also studied the origin ofclinopyroxenes in kimberlites, p-T conditions for their formation and their reflected tectonic environments ofthe kimberlite formation. He suggests that this mineral is an indicator for diamond exploration.

关键词： kimberlites clinopyroxenes geochemistry

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THE pRESENT SITUATION OF THE DEVELOpMENT OF RARE EARTHS IN china

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Journal of Rare Earths 1990年第1期8卷 67-73页

作者： Liu Yujiu(Bureau of Rare and Rare Earth Metals,china National Nonferrous Metals Industry Corporation,Beijing p.R.china)

*** Earth Resources in *** and distributionchina is the country which is the richest in the world in rare earth(RE)resources of allavailable varieties of minerals and their deposits are located in vast areas in *** been estimated at a grand total of 36 million ton,which is 80% of the world(RE)*** majority of these deposits are concentratedly located in Baiyunebo mine of the

关键词： RE THE pRESENT SITUATION OF THE DEVELOpMENT OF RARE EARTHS IN china

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Sulfide-melt inclusions in mantle xenoliths of Hannuoba,china

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Chinese Science Bulletin 1999年第2期44卷 166-170页

作者： XU Jiuhua , CHU Xuelei , ZHOU Yiming , DU YuanfuUniversity of Science and Technology Beijing, Beijing 100083, china china University of Geosciences( Beijing) , Beijing 100083, china The Research Center of Mineral Resources Exploration , Beijing 100101, china Institute of Geology, Chinese Academy of Sciences, Beijing 100029, china University of Science and Technology Beijing Beijing China china University of Geosciences (Beijing) Beijing China The Research Center of Mineral Resources Exploration Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Sulfide fluid incluision study on mantle xenoliths of Hannouba has been carried out by EpMA analysis. It is indicated that the Ni/Fe ratios of metal sulfides in sulfide-melt inclusions from Hannuoba seem to be related to host rocks. These data of lherzolite （pentlandite） are obviously higher than those of olivine pyroxenite （mainly pentlandite, partly pyrrhotine）. The LRM analysis shows that sulfur （H2S+SO2） occupies larger proportion in gas composition of CO2 fluid inclusions, generally more than mol 20 %. This may be related to sulfide inclusions which are frequently found.

关键词： mantle xenolith sulfide-melt inclusion EpMA.

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