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TOPOLOGICAL CONFIGURATIONS OF POSSIBLE REAL NETS IN BINARY n+m(m≥3) PHASE MULTISYSTEMS

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science in China,Ser.B 1986年第10期29卷 1096-1109页

作者：程伟基 department of earth and {2. sciences university of science and {2. of China hefei

This paper further summarizes the method and results developed to find all possible real nets in binary n+3 phase multisystems, and emphasizes that there is a definite relationship between configurations and symbols of stable and metastable invariant points of nets or positions of phases as symbols on the chemographic bar. On the basis of these, a general principle is developed to construct and check possible neets in binary n+m (m>3) phase multisysterns: this sort of nets must be the reasonable combination of one or more than one distinct binary n+3 phase multisystem subnets, in which the number of points missing respectively same m—3 phases in n+3. Therefore, the binary n-4.3 phase nets are basic construction units of the binary n+m(m>3) phase nets. As an instance, the maximum partially closed net in binary n+4.phase multisystems, which has the most stable invariant points, is constructed, and it is indicated that this sort of net is unique.

关键词： PHASE MULTISYSTEMS TOPOLOGICAL CONFIGURATIONS OF POSSIBLE REAL NETS IN BINARY n+m net NETS

The Thermal History of the Huangmeijian Granite Intrusion in Anhui and Its Relation to Mineralization: Isotopic Evidence

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Acta Geologica Sinica(English Edition) 1996年第2期70卷 168-180页

作者： Zheng Yongfei Fu Bin and Gong Bing department of earth and {2. sciences, {4. of science and technology of China, hefei 2.002. Liu Xinzhu department of earth and {2. sciences University of Science and Technology of China Hefei 230026

Whole-rock Rb-Sr, zircon U-Pb and hornblende, biotite and K-feldspar K-Ar ages areused to reconstruct the cooling history of the Huangmeijian intrusion in the Anqing-Lujiangquartz-syenite belt in Anhui. Oxygen isotope geothermometry of mineral pairs demonstrates thatdiffusion is a dominant factor controlling the closure of isotopic systems. Assuming the coolingof the intrusion is synchronous with a dicrease in local geothermal gradients, an emplacementdepth of about 8 km and the magma crystallization temperature of 800±50℃ are estimated. TheHuangmeijian intrusion experienced a rapid cooling process and uplifted after its emplacementand crystallization at 133 Ma B.P. with a cooling rate of 34.5℃/Ma and an uplifting rate of 0.35mm/a. The intrusion was rising until it rested at a depth of 3km at a temperature of 300±50℃about 14.Ma later. Then the intrusion was in slow cooling and uplifting with a cooling rate of4.4./Ma and an uplifting rate of 0.04.mm/a. U-Pb dating of pitchblende is done for the hydrothermal uranium deposit formed in thecontact zone of the Huangmeijian intrusion. The result shows that the mineralization age is closeto the closing time of the K-Ar system in biotite. The fluid inclusion thermometry indicates thatthe mineralization temperature is in agreement with the closure temperature of the biotite K-Arsystem. This suggests a close relationship between the slow cooling of the intrusion and thehydrothermal uranium mineralization process.

关键词： quartz syenite isotopic age oxygen isotope cooling history mineralization rate control

Mineral Composition and Metamorphic P-T Conditions of the Eclogitic Rocks in the Eastern Dabie Mountains and Their Genetic Implication

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Acta Geologica Sinica(English Edition) 1993年第4期67卷 387-402页

作者： Ge Ningjie, Li Shuguang, Peng Zhonghua and Liu Deliang department of earth and {2. sciences, {4. of science and technology of China, hefei, Anhui Jiang Minxi department of earth and {2. sciences University of Science and Technology of China Hefei Anhui

There are obvious differences in the mineral assemblage and metamorphic P-T conditions between the eclogites from the northern and southern parts of the eastern Dabie Mountains. Those from the northern part of the mountains are developed in Alpine peridotite and gneiss. They have a mineral assemblage of garnet+diopside with no quartz, and were formed at temperatures of 600℃-74.℃. Those from the southern part are developed in gneiss and marble. They consist of garnet+omphacite+less quartz and were metamorphosed at temperatures in the range of 650°-800℃. These differences suggest that the former may be formed during the metamorphism of the deep subducted oceanic crust, whereas the latter may be genetically related to the subduction of the continental crust in this area.

关键词： collisional orogen eclogitic rocks from the southern and northern parts of the Dabie Mountains T-P conditions

Genesis of excess argon in phengite and significance of ^(4.)Ar-^(39)Ar age spectra for omphacite:A case study on UHP eclogite of South Dabie Terrain,China

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Chinese science Bulletin 2000年第15期45卷 1345-1351页

作者： WANG Songshan, GE Ningjie, SANG Haiqing & QIU Ji1. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 10002., China 2. department of {2. and space {4., university of {4. and technology of China, hefei 2.002., China Correspondence should be addressed to Wang Songshan Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China department of earth and {2. science University of Science and Technology of China Hefei China

The Ar-Ar dating of phengite and omphacite in ultrahigh-pressure (UHP) eclogite of Bixiling and Hengchong in the South Dabie Terrain shows that the content range of excess argon is as high as (0.4.1.3)×10 8 mol· g 1. The genesis of the excess argon is discussed. The Ar-Ar age spectra of omphacite could not support the opinion that the UHP metamorphism occurred in Caledon epoch and pre-Caledon epoch.

关键词： South Dabie Terrain ultrahigh-pressure metamorphics phengite omphacite excess argon.

Re-Os isotopic system and formation age of subcontinental lithosphere mantle

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Chinese science Bulletin 2000年第3期45卷 193-200页

作者： ZHI Xiachendepartment of earth and {2. sciences, {4. of science and technology of China, hefei 2.002., China Advance Research Center for earth science and Astronomy, USTC, Third World Academy of science, hefei 2.002., China Laboratory of Chemical Geodynamics, USTC, hefei 2.002., China department of earth and {2. sciences University of Science and Technology of China Hefei China Advance Research Center for earth science and Astronomy USTC Third World Academy of Science Hefei China Laboratory of Chemical Geodynamics USTC Hefei China

The determination of the formation age of subcontinental Lithosphere Mantle (SCLM) is a widely concerned issue in mantle geochemistry. it is difficult to obtain the formation age of SCLM using lithophile isotopic systems such as Rb-Sr, Sm-Nd, U-Th-Pb, ete., but as siderophile elements, the Re-Os isotopic system provides a powerful tool for that work. Here a comprehensive review on the recent development in Re-Os dating for SCLM has been given.

关键词： Re-Os isotopic dating subcontinental lithospheric mantle mantle derived peridotites Re depleted model age whole rock isochronological age.

Paleotemperature changes over the past 3000 years in eastern Beijing, China: A reconstraction based on Mg/Sr records in a stalagmite

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Chinese science Bulletin 2003年第4期48卷 395-400页

作者： MA Zhibang1, LI Hongchun2. XIA Ming1, KU Tehlung2. PENG Zicheng3, CHEN Yushu4.& ZHANG Zhaofeng3 1. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 10002., China 2. {2. of {2. sciences, {4. of Southern California, Los Angeles, CA90089-074., USA 3. {2. of {2. and space science, {4. of science and technology of China, hefei 2.002., China 4. Beijing Foshan Tourist Service Centre, Beijing 1012.1, China Institute of Geology and Geophysics. Chinese Academy of sciences Beijing 100029 China

The Mg/Sr ratio in a stalagmite, which is di-rectly proportional to DMg/Ca, the solid-liquid distribution coefficient of Mg, is proposed as a geochemical thermometer to estimate paleotemperature changes. The paleotempera-ture change in eastern Beijing over the past 3000 years has been reconstructed by using this thermometer in the stalag-mite ZFFS-1 from Jingdong Cave. The records can be di-vided into two periods: 3000—2.00 aBP, cool and wet, the air temperature averaging 9.8℃; and 2.00 aBP—present, hot and dry, the air temperature being 1℃ higher than the mean value (11.7℃) of the past 3000 years. During 500—2.0 aBP, the air temperature was about 1.2. lower than that of the present, corresponding to the Little Ice Age in Europe. Like d 18O and d 13C, Mg/Sr (or DMg/Ca) reflects an obviously warming trend of the past 2.0 years. These results are sup-ported by historic records.

关键词：北京京东溶洞石笋 Mg/Sr记录古气温测年 3000年

Pleonaste in Boxian meteorite

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Chinese science Bulletin 1998年第19期43卷 1656-1660页

作者： WANG Kuiren and HONG Ji’an department of earth and {2. sciences, {4. of science and technology of China Advanced Research Center for earth sciences and Astronomy, {4. of science and technology of China, Third World Academy of sciences department of earth and {2. sciences University of Science and Technology of China China Advanced Research Center for earth sciences and Astronomy University of Science and Technology of China Third World Academy of Sciences Hefei China

There are three kinds of occurrence of pleonaste, a rare meteoritic mineral, totally found in Boxian meteorite. They are as the following: (ⅰ) occurring in the inner circle of the chondrule edge, of which a circle texture is composed; (ⅱ) occurring in the state of inclusions, included in an olivine chondrule, with close paragenesis of wadsleyite; (ⅲ) occurring in the state of porphyry. The chondrule in the first occurrence belongs to CA chondrules. The chemical compositions of pleonaste are heterogeneity except for the atomic ratios of Fe/(Mg+Fe), which can be attributed to the following reasons: (ⅰ) they are congenetic minerals; (ⅱ) the heterogeneity of the compositions of the solar clouds in the early states; (ⅲ) the chondrites are the multiple-stage evolution; (ⅳ) the further proof of Boxian meteorite is an unequilibrium common chondrite.

关键词： rare pleonaste in meteorites found genesis.

Pb isotope geochemistry of lead, zinc, gold and silver deposit clustered region, Liaodong rift zone,northeastern China

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science China earth {2. 2005年第4期48卷 467-476页

作者： CHEN Jiangfeng1, YU Gang1, XUE Chunji2. QIAN Hui1, HE Jianfeng1, XING Zhi1 & ZHANG Xun1 1. School of earth and space {2., university of {4. and technology of China, hefei 2.002., China 2. department of Geology, Chang’an university, Xi’an 710054. China 1. School of earth and space {2. University of Science and Technology of China 230026 Hefei China 2. department of Geology Chang’an University 710054 Xi’an China

Pb isotopic analyses were reported for sulfide and hydrothermal carbonate minerals and marble of the Xiquegou lead-zinc, the Zhenzigou zinc-lead and the Gaojiapuzi silver deposits from the Qingchengzi ore field and the Beiwagou zinc-lead deposit in the west, Proterozoic Liaodong rift zone. Pb isotopic ratios of the marble from the Qingchengzi ore field range from 18.2.0}to 30.63 for 2.6 Pb/2.4.b, 15.59 to 17.05 for2.7Pb/2.4.b and 37.4. to 38.63 for 2.8Pb/2.4.b. The marble gives a Pb-Pb isochron age of 182.±92.Ma, which is interpreted as the age of the metamorphism of the marble. Ore Pb, including Pb of sulfide and hydrothermal car- bonate minerals, from the Qingchengzi ore field shows limited variation with 2.6 Pb/2.4.b=17.66- 17.96, 2.7 Pb/2.4.b=15.60-15.74.and 2.8Pb/2.4.b=37.94.38.60. In contrast, ore Pb from the Beiwagou deposit gives different Pb isotopic ratios with 2.6Pb/2.4.b=15.68-15.81, 2.7 Pb/2.4.b= 15.34.15.4. and 2.8Pb/2.4.b=35.30-35.68. Pb of all deposits from the Liaodong rift zone is derived from the upper crust. Ore Pb of the Qingchengzi deposits is derived from a young upper crust. The model Th/U ratios of 4.4. to 4.74.for ore Pb are significantly different from that of 1.7 to 4.4.given by the marble of the Qingchengzi ore field, suggesting that marble is not the source of the ore Pb. Ore Pb of the Beiwagou deposit is extracted from its source and the deposit is formed at the Paleoproterozoic era. Different Pb isotopic ratios of the Qingchengzi ore field and the Beiwagou deposit are due to different ages of the deposits and suggest that the two types of deposits are derived from different sources and are possibly formed by different ore-forming processes.

关键词： Pb isotopes, source(s) of the ore-forming materials, origin of ore deposits, Liaodong rift zone.

Discovery and analysis of ultra-micro grinding grain texture in slipping lamellae of ductile-brittle zone

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science China earth {2. 2004年第3期47卷 265-271页

作者： GE Heping1, SUN Yan1, LU Xiancai1, ZHU Wenbin1, GUO Jichun1, LIU Deliang2.& Chi-yuen Wang3 1. department of earth {2., Nanjing university, State Key Laboratory of Mineral Deposit, Nanjing 2.0093, China 2. department of earth and space {2., university of science and technology of China, hefei 2.002., China 3. department of Geology and Geophysics, university of California, Berkeley, CA 94.2., USA Nanjing Univ Dept Earth Sci State Key Lab Mineral Deposit Nanjing 210093 Peoples R China Univ Sci & Technol China Dept Earth & Space Sci Hefei 230026 Peoples R China Univ Calif Berkeley Dept Geol & Geophys Berkeley CA 94720 USA

Based on the observation of the deep bore cores sampled from the State of Cali-fornia, USA, preferred arranged particulate concentration belts were found in the ultra-slipping lamellae. And the same phenomenon was found again later in the bore cores from the petroleum basin in the Northern Shaanxi Province. It may be the product of the dynamic processes involv-ing tumbling, grinding and compresso-shearing functions, so the spherical particulates with ul-tra-size of nm and mm are called grinding grain. The formation of the grinding grains is related with the ductile-brittle deformation, the lateral pressure of the slipping, and the very low grade of dynamic metamorphism of the rocks. Based on the systematic analysis, it is indicated that some elements like Nb and Ta are enriched in the grinding grains in the granitic rocks because of the chemical differentiation, and that the slipping lamellae bearing grinding grains in mudstone with smear efficiency prove a perfect seal for oil and gas reservoirs. Meanwhile, the paper provides bases for the studies on the fast stick-slip movement and shear paradigm.

关键词： slipping lamellae, grinding grain texture, ductile-brittle deformation, smear efficiency.