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CARBONATITES FROM THE EASTERN HIMALAYAN SYNTAXIS: PETROLOGY AND TECTONIC IMPLICATIONS

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地学前缘 2000年第S1期7卷 10-11页

作者： Liu Yan 1, Zhong Dalai 2. Ji Jianqing 3(1 institute of geology, {2. academy of geological Sciences, beijing 100037, china 2.institute of geology & Geophysics, {2. academy of Sciences, beijing 10002., china 3 Department of geology, Pek

Most carbonatites occur in relatively stable, intra\|plate areas but some are found to occur in near to plate margins and may be linked with plate separation (Woolley, 1989). Although many carbonatites have been discovered to occur in the orogenic belts in recent years, most of these rocks are related to post\|orogenic magmatism, that is, the rocks occur in the specially extensional setting. Therefore it is unusual that such magmatic rocks occur in the typical convergent environment. Here we report carbonatites and associated ultramafic and mafic rocks in the core of the eastern Himalayan syntaxis. The eastern Himalayan syntaxis consists of three tectonic units: the Gangdise, the Yarlung Zangbo, and the Himalayan units, each of which is bounded by faults (Liu & Zhong, 1997). The Himalayan unit, the northernmost exposed part of the Indian plate, is divided into two complexes, the amphibolite facies complex in the south and the granulite facies complex in the north. The granulite facies complex in the Himalayan unit have been argued to experience high\|pressure metamorphism and represent materials buried to upper\|mantle depths (Liu & Zhong, 1997). The carbonatites and associated ultramafic and mafic rocks only occur in the granulite facies rocks and are divided into two belts: northern and southern *** northern belt extends at least 30km, and is about 2.km in width. The southern belt extends several kilometers, and is 3km or so in width. Each belt consists mainly of differently compositional dykes, extending parallel to gneissosity of granulite facies gneiss. Carbonatitic agglomerates are observed in the northern belt. From the center of carbonatite dykes to country rocks, five types of rock are observed: the center parts of carbonatites, the rim parts of carbonatites, ultramafic and mafic rocks, altered rocks and country rocks. The gneissosity of country rock was deformed by intrusion of dykes.

关键词： Eastern Himalayan Syntaxis carbonatites ultramafic rocks carbonatitie magmatism convergent environment

Malanite——A New Cupric Platinum (Pt^(3+)) and Iridium (Ir^(3+)) Sulphide

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Acta Geologica Sinica(English Edition) 1997年第2期71卷 152-157,233页

作者： Yu Zuxiang institute of geology, {2. academy of geological Sciences, beijing, 100037 institute of geology Chinese Academy of Geological Sciences Beijing 100037 [?]Yu Zhuxiang Born in Nov. 1930 graduated from the Specialty of Petrology and Mineralogy of the Department of geology Beijing College of Geology in 1953. He has long engaged in the study of mineralogy as Research Professor at the Institute of Geology Chinese Academy of Geological Sciences.

Malanite was first found in veinlets of disseminated copper-nickel ores inZunhua County, Hebei Province, and then in platinum-bearing chromite ores in ShuangfengVillage, Yanshan. In the former case, malanite appears as octahedrons or dodecahedrons asso-ciated with pyrrhotite, pentlandite, sperrylite and cooperite; while in the latter case, it is massiveor present in anhedral glomerocrysts, filling in cracks of iridisite and associated with osmiride,ferrian platinum and iridisite. Malanite is steel-grey in colour, opaque with metallic lustre andblack streaks and brittle with no magnetism. H_M=5.0, VHN_(2.)=417kg/mm^2. cleavage {111}sometimes observed. The calculated density is 7.57g/cm^3. The reflective colour is white with alight green tint. Internal reflections are not observed. This mineral is isotropic, showing nobireflection or reflection pleochroism in air. By means of electron microprobe analysis, the em-pirical formula (based on 7 atoms) is expressed as (Cu_(0.93)Fe_(0.06))_(∑0.99)(Pt_(1.03)Ir_(0.66)Rh_(0.04)Pd_(0.03)Co_(0.2.)Ni_(0.03))_(1.99)S_(4.03) or (Cu_(0.95)Fe_(0.07))_(∑1.02.(Pt_(1.37)Ir_(0.45)Co_(0.11)Rh_(0.08))_(∑2.01)S_(3.97). Five strongestlines (hkl, d, I) of X-ray powder diffraction data of malanite are 311,2.98(6); 400,2.48(5);333, 1.90(7); 440, 1.75(10); 731, 1.2.(5). It was known on the basis of X-ray powder diffractiondata that malanite is cubic, and the space group is Fd3m with α=0.9940nm, V=0.982.(3)nm^3 and Z=4. The type material of malanite is deposited at the geological Museum of china(GMC)s

关键词： new mineral malanite chrome ore

geological analysis and physical modeling of structural pumping in high effective formation of Kela 2.gas field

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Science china Earth Sciences 2006年第10期49卷 1070-1078页

作者： ZHAO Wenzhi1, WANG Hongjun1, SHAN Jiazeng2. WANG Zecheng1 & XU Dafeng1 1. Research institute of Petroleum Exploration and Development, Petrochina, {2. 100083, china 2. institute of geology and Geophysics, chinese academy of Sciences, {2. 10002., china 1. Research institute of Petroleum Exploration and Development Petrochina Beijing 100083 China 2. institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

In a 3-D closed geological body, in case “structural expanding” inside is induced by stress, it can produce the pressure difference between the expanding cell and surrounding rock, then generate a pumping force directed toward the cell and accelerate the directional flow of fluid in the strata. The structural style and conditions of gas reservoir-formation in the Kuqa depression are favorable to the structural pumping. According to similarity principle, a physical modeling of structure formation and gas filling process of the Kela 2.gas field has justified the occurrence of structural pumping and its important role in gas-reservoir formation with high efficiency under the compressive and well-sealed circumstance. Therefore, authors propose that structural pumping is an important mechanism of gas reservoir-formation with high efficiency in the Kuqa depression.

关键词： Kela 2 gas field, structural pumping, gas-reservoir formation mechanism, high efficiency,physical modeling.

Evaluation of the Interfacial Adhesion between Brittle Coating and Ductile Substrate by Cross-Sectional Indention

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材料热处理学报 2004年第5B期25卷 1187-1190页

作者： SUJian-yu ZHANGKun CHENGuang-nan instituteofMechanics ChineseAcademyofSciencesBeijingChina／／GraduateSchooloftheChineseAcademyofSciencesBeijingChina instituteofMechanics ChineseAcademyofSciencesBeijingChina

The cross-sectional indentation method is extended to evaluate the interfacial adhesion between brittle coating and ductile substrate. The experimental results on electroplated chromium coating/steel substrate show that the interfacial separation occurs due to the edge chipping of brittle coating. The corresponding models are established to elucidate interfacial separation processes. This work further highlights the advantages and potential of this novel indentation method.

关键词：分界面附着刻痕可锻衬底应力涂层铬钢

Climatic and environmental changes over the last millennium recorded in the Malan ice core from the northern Tibetan Plateau

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Science china Earth Sciences 2006年第10期49卷 1079-1089页

作者： WANG Ninglian1,2. YAO Tandong2.1, PU Jianchen1, ZHANG Yongliang1 & SUN Weizhen1 1. Key Laboratory of Cryosphere and Environment, Cold and Arid Regions Environmental and Engineering Research institute, chinese {2. of Sciences, Lanzhou 730000, china 2. institute of Tibetan Plateau Research, chinese {2. of Sciences, beijing 100085, china 1. Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

In this paper, climatic and environmental changes were reconstructed since 112.A.D. based on the Malan ice core from Hol Xil, the northern Tibetan Plateau. The record of δ 18O in the Malan ice core indicated that the warm-season air temperature variations displayed a general increase trend, the 2.th-century warming was within the range of natural climate variability, and the warmest century was the 17th century while the warmest decade was the 1610s, over the entire study period. The “Medieval Warm Epoch” and “Little Ice Age” were also reflected by the ice core record. The dust ratio in the Malan ice core is a good proxy for dust event frequency. The 870-year record of the dust ratio showed that dust events occurred much frequently in the 19th century. Comparing the variations of δ 18O and the dust ratio, it is found that there was a strong negative correlation between them on the time scales of 101―102.years. By analyses of all the climatic records of ice cores and tree rings from the northern Tibetan Plateau, it was revealed that dust events were more frequent in the cold and dry periods than in the warm and wet periods.

关键词： the Tibetan Plateau, the Malan ice core, climate changes, dust event frequency.

Y_CΩ_(2.)are easy terms

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chinese Science Bulletin 1998年第20期43卷 1707-1709页

作者： ZHAO Xishun 1 and WANG Ju 2.1. Department of Mathematics, Nanjing University, Nanjing 2.0093, china 2. institute of Software, {2. academy of Sciences, beijing 100080, china Department of Mathematics Nanjing University Nanjing China institute of Software Chinese Academy of Sciences Beijing China

For any natural number n≥1, Y CΩ 2. is an easy term; that is, for any λ term M, λβ+Y\-CΩ 2. =M is consistent, where Y C is Curry fixed point combinator, Ω 2. ≡ω 2. ω 2. and ω 2. ≡λ***...x (there are 2. occurrences of x after λx ). This result is a partial solution to Jacopini’s conjecture: Y CΩ n is an easy term for any natural number n≥2.

关键词： λβ-calculus Kuper’s theorem easy term.

Oxygen isotope compositions of eclogites in Rongcheng,Eastern china

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chinese Science Bulletin 2003年第4期48卷 372-378页

作者： CHU Xuelei1,2. GUO Jinghui1,2. FAN Hongrui1,2.& JIN Chengwei1 1. institute of geology and Geophysics, {2. academy of Sciences, beijing 10002., china 2. Key Laboratory for Mineral Resources Research, {2. academy of Sciences, beijing 100101, china Correspondence should be addressed to Chu Xuelei institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Key Laboratory for Mineral Resources Research Chinese Academy of Sciences Beijing 100101 China

Collected from the Rongcheng region, Shan-dong Province, the three types of eclogites suffering the UHP (i.e. ultra-high pressure) metamorphism have obviously dif-ferent oxygen isotope compositions. The eclogites occurring in regional orthogneisses and ultramafic rocks have the oxy-gen isotope compositions of normal eclogites in the world,but the eclogites existing in marbles are extremely enrichedin 18O. By applying oxygen isotope geothermometry, for theall types of eclogites, the temperature estimates of quartz-garnet pair, in principle, indicate the formation temperatures of eclogites, so that the peak-metamorphic temperatures are estimated to be averagely little higher than 800℃, which are consistent with the estimates by using other geothermome-ters according to cation partitioning between coexistingphases. The d 18O values of eclogitic inclusions hosted inmarbles from Yangguantun, Rongcheng region, are farhigher than the values of eclogites (including eclogitic inclu-sions in marbles) from the Dabieshan and other places of the Sulu. The oxygen isotope compositions of various mineralsindicate that the formation temperatures of eclogites fromthe Rongcheng region, in general, are higher than that from the Dabieshan and the southwestern part of the Sulu, but the dispersive temperatures estimated by different mineral pairs probably reflect that the UHP eclogites from the Rongcheng region generally suffered overprinted metamorphisms dur-ing the exhumation.

关键词：苏鲁超高压变质带 UHP 山东荣成榴辉岩氧同位素成分

Geochemical simulation of the formation of brine and salt minerals based on Pitzer model in Caka Salt Lake

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Science china Earth Sciences 2004年第8期47卷 720-726页

作者： LIU Xingqi1, CAI Keqin2.& YU Shengsong3 1. Nanjing institute of Geography and Limnology, chinese {2. of Sciences, Nanjing 2.0008, china 2. china University of Geosciences, beijing 100083, china 3. institute of Salt Lakes, chinese {2. of Sciences, Xining 810008, china 1. Nanjing institute of Geography and Limnology Chinese Academy of Sciences 210008 Nanjing China 2. china University of Geosciences 100083 Beijing China 3. institute of Salt Lakes Chinese Academy of Sciences 810008 Xining China

The geochemical simulation of the formation of brine and salt minerals based on Pitzer model was made in Caka Salt Lake. The evolution of the mixed surface-water and the mineral sequences were calculated and compared with the hydrochemical compositions of the brine and the salt minerals of the deposit in Caka Salt Lake. The results show that the formation temperature of the lake is between 0°C and 5°C, which is well identical with other studies. The mixing of salt-karst water with the surface waters, neglected by the former researchers, is very important to the formation of the lake, indicating that the initial waters resulting in the formation of the lake are multi-source. It is the first time to use Pitzer model in china for making geochemical simulation of the formation and evolution of inland salt lake and satisfactory results have been achieved.

关键词： Pitzer model,Caka Salt Lake,geochemical simulation,salt-karst water.

SHRIMP U-Pb dating and Hf isotopic analyses of Middle Ordovician meta-cumulate gabbro in central Qiangtang, northern Tibetan Plateau

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Science china Earth Sciences 2010年第5期53卷 657-664页

作者： ZHAI QingGuo1 WANG Jun1, LI Cai2.& SU Li3 1 institute of geology, {2. academy of geological Sciences, beijing 100037, china 2.College of Earth Sciences, Jilin University, Changchun 130061, china 3 The geological Laboratory Center and State Key Laboratory of geological Processes and Mineral Resources, china University of Geo- sciences, beijing 100083, china 1. institute of geology Chinese Academy of Geological Sciences Beijing 100037 China2. College of Earth Sciences Jilin University Changchun 130061 China3. The Geological Laboratory Center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon SHRIMP U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.2.2.15 to 0.2.2.57, with εHf(t) values of 5.02.0.2., indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro SHRIMP dating Hf isotope