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Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science china Earth sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3 1. Faculty of Earth sciences and Natural Resources, china University of Geosciences, beijing 100083, china 2. Faculty of Earth sciences, china University of Geosciences, Wuhan 4.0074. china 3. beijing SHRIMP Center, Institute of {12., chinese academy of Geological sciences, beijing 100037, china Faculty of Earth sciences and Natural Resources China University of Geosciences Beijing China Faculty of Earth sciences China University of Geosciences Wuhan China beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 72. and 773 Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2.0}8 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

Project research of GIS data based on AutoCAD

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中国有色金属学会会刊：英文版 2005年第S1期15卷 244-246页

作者： YAO Xin ~(1, 2. (1. Institute of geology and geophysics,{2., beijing 10002.,{4. 2. The Geomatics and Applications Laboratory, Liaoning Technical University, Fuxin 12.000,{4.) chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Liaoning Tech Univ Geomat & Applicat Lab Fuxing 123000 Peoples R China

The digitalization software developed based on AutoCAD is one important platform of GIS data gather. But because AutoCAD itself is not the software of GIS, it can not be used to collect the attribute data. And conversion data to GIS software often lose some information such as color, line style, symbol shape. By using the XDATA, the Handle, the Group of AutoCAD and the provided ObjectArx to Redevelop, under AutoCAD condition, the attribute information collection with space information were realized, also did the AutoCAD symbol integrity and accurate expresses, then the demand of the digit graphics was satisfied.

关键词： AutoCAD attribute data data transfer ObjectArx XDATA

δ^13Csc values of the loess-paleosol sequence in Dali area, Shaanxi Province, china, and paleoenvironmental implications

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chinese Science Bulletin 2003年第9期48卷 902-907页

作者： LI Yumei & LIU Dongsheng (LIU Tungsheng)Institute of geology and geophysics,{2., beijing 10002. (e-mail: liyrney@***) Institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China

The carbon isotopic ratios of carbonate in the two profiles of the Dali area were analyzed and some new understandings on the influencing factors of the δ13CSC value of the loess-paleosol sequence and its paleoenvironmental implications were discussed preliminarily in this report. The 13CSC value of the Dali loess-paleosol sequence is synchronizing with the variance of magnetic susceptibility basically and the negative peaks of the δ13CSC curves are corresponding to the different developmental periods of the paleosol. It is believed that the intervention of the CO2.produced by plants will cause the decrease of the δ13CSC value, the amplitude of which may be relevant to the paleovegetation density and the ancient humidity. The relative biomass of C4.plants in the vegetation will affect the sublevel change of the δ13CSC. Low δ13CSC value by and large indicates the environmental conditions of the relatively abundant vegetation and humid climate. During the last 2.0000 years, the period with the sparsest vegetation and the most arid climate is the phase of the loess in L2.depositing and the period with the most abundant vegetation and the most humid climate is the last interglacial period. The δ13CSC curves of Dali also show that the High Temperature and Large Precipitation Event of the Qinghai-Tibetan Plateau during 4.-30 kaBP had affected the Central Shaanxi Plain with relatively humid climate, and had apparent influence on the local vegetation and humidity.

关键词：古环境大理地区黄土陕西湿润气候碳同位素植被高温天气

The high-resolution climate recorded in the δ^(18)O of Porites lutea from the Nansha Islands of china

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chinese Science Bulletin 2001年第24期46卷 2097-2102页

作者： YU Kefu, CHEN Tegu, HUANG Dingcheng, ZHAO Huanting, ZHONG Jinliang & LIU Dongsheng (LIU Tungsheng)South china Sea Institute of Oceanoiogy, chinese academy of sciences. Guangzhou 510301, china:geology and {4. Institute. chinese academy of sciences, beijing 10002., china South china Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China geology and geophysics Institute Chinese Academy of Sciences Beijing China

A Porites lutea core from Yongshu Reef of Nansha Islands covering 50 years growth history was ana-ly/ed for oxygen isotopic composition with monthly and seasonally resolution. The calibration of the δ18O with the instrumental temperature indicated that the coral δ18O is a good indicator for sea surface temperature (SST) and air temperature (t). It can be used to reconstruct the SST and air temperature of the Yongshu Reef sea area. In addition, the coral δ18O provides signatures for the intensity of the East Asia monsoon and it is a record for the activities of El Nino events. With the calibrated SST and air temperature formulas, the most recent fifty years SST and air temperature were reconstructed based on the coral δ18O, thus back up the understanding of the climate of Nansha Islands to 1950. far beyond the limit of the instrumental recording since September 1988. It was found that, in general, increasing 1℃ air temperature results in 0.2.0}decrease in skeletal δ18O.

关键词： Nansha Islands Porites lutea δ18O sea surface tem-perature East Asia monsoon.

Genetic Mechanism of Mineral Inclusions in Zircons from the Khondalite Series, Southeastern Inner Mongolia

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 28-35页

作者： LIU Fulai and SHEN Qihan Institute of geology, chinese {2. of Geological sciences, {4. 100037 chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China

The early Precambrian khondalite series is widely distributed in theJining-Zhuozi-Fengzhen-Liangcheng area, southeastern Inner Mongolia. The khondalite series mainlyconsists of sillimanite garnet potash feldspar (or two-feldspar) gneiss and garnet biotiteplagioclase gneiss. These gneissic rocks have commonly experienced granulite-facies metamorphism. Inzircons separated from sillimanite garnet potash feldspar gneisses, many mineral inclusions,including Sil, Grt, Ky, Kfs, Qtz and Ap, have been identified by the Laser Raman ***, prograde metamorphic mineral inclusion assemblages such as Ky + Kfs + Qtz + Ap and Ky +Grt + Kfs + Qtz are preserved in the core of zircon, while peak granulite-facies metamorphicminerals including Sil + Grt + Kfs + Qtz and Sil + Gif + Kfs + Qtz + Ap are identified in the mantleand rim of the same zircon. However, in some zircons are only preserved the peak metamorphicminerals such as Sil + Grt + Kfs + Qtz and Sil + Grt + Kfs + Qtz + Ap from core to rim, and inothers are inherited the primary cores with minor mineral inclusions of Kfs + Qtz, with peakmetamorphic mineral inclusions around the inherited cores. These data indicate that the mineralassemblage evolution of sillimanite garnet potash feldspar gneisses in the study are did experiencea polymorphic transformation of kyanite to sillimanite. In garnet biotite plagioclase gneisses,secondary electron microscopic images reveal that most zircons display distinct zoning textures,which comprise cores and rims, each with distinctive inclusion assemblages. The inherited mineralinclusions, mainly consisting of Kfs + Pl + Qtz, Kfs + Qtz and Kfs + Qtz + Ap, are preserved in theprimary cores, while peak granulite-facies mineral asemblages, including Grt + Bt + Pl + Qtz + Ap,Grt + Bt + Pl + Qtz and Grt + Bt + Pl + Qtz + Rt, are identified on the rims. The occurrence of peakmetamorphic mineral inclusions in zircons indicates that these gneissic rocks, includingsillimanite garnet potas

关键词： mineral inclusion zircon Laser Raman secondary electron microscopy genetic mechanism khondalite series Inner Mongolia

Two new reinforcement techniques applicable in high steep slopes along the Chengdu-Lhasa Highway, Southwest china

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Science china(Technological sciences) 2003年第Z1期46卷 156-162页

作者： YANG ZhifaZHU Jiewang ZHANG Luqing, CUI Peng, LI Xiao & SHANG Yanjun Institute of geology and geophysics,{2., beijing 10002.,{4. Institute of Mountain Hazards and Environment,{2. and Ministry of Water Resources, Chengdu 61004.,{4. chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China

Anti-slide pile and anchoring hole are two types of reinforcement techniques popularly used in slope reinforcement. However, some defects of these two techniques are found in slope engineering practices. Utilizing higher tensile strength of pre-stressed structures, the authors devise two new types of slope reinforcement techniques, i.e. pre-stressed anchoring beam and pre-stressed anti-slide pile, in an attempt to overcome those defects of the existing techniques. These two new techniques are characterized by gathering multiple functions, e.g. engineering investigation, reinforcement, drainage, monitoring and strength supplement, so as to achieve high reinforcement efficiency, convenient checking, and higher ratio of function to cost. It is hoped that, if applying these two new techniques in remedies of landslide hazards along the Chengdu-Lhasa Highway, better reinforcement effects will be obtained.

关键词： rock slope, pre-stressed anchoring beam, pre-stressed anti-slide pile.

Dehydration melting of solid amphibolite at 2.0 GPa: Effects of time and temperature

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Science china Earth sciences 2005年第8期48卷 1120-1133页

作者： ZHOU Wenge1, XIE Hongsen1, LIU Yonggang1, ZHENG Xiaogang1, ZHAO Zhidan2.& ZHOU Hui3 1. Laboratory of Material in the Earth’s Interior, Institute of Geochemistry, chinese academy of sciences, Guiyang 550002. china 2. Department of {2., china University of Geo{4., beijing 100083, china 3. Department of {2., Peking University, beijing 100871, china Laboratory of Material in the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences Guiyang China Department of geology China University of Geosciences Beijing China Department of geology Peking University Beijing China

Two sets of dehydration-melting with a natural solid amphibolite, collected from North Himalayan structure zone, Tibet, have been carried out in multi-anvil apparatus at 2.0 GPa and 800―1000℃, for 12.2.0 h. One is keeping the pressure at 2.0 GPa and the annealing time of 12.h, changing the temperature (800―1000℃). The other is keeping the pressure at 2.0 GPa and temperature at 850℃, varying the annealing time (12.2.0 h). The products are inspected with microscope and electron probe. The results indicate that at 2.0 GPa, annealing time of 12.h, garnets, melts and clinopyroxenes occur in amphibolite gradually with increasing temperature and the chemical compositions of melt vary from tonalite to granodiorite, and then to tonalite. However, at 2.0 GPa and 850℃, with the annealing time increasing, the garnets, melts and cli-nopyroxenes also occur in amphibolite gradually and the chemical compositions of melt vary from tonalite to granodiorite. In both cases, melts interconnect with each other when the contents of melt are over the 5 vol.%. the viscosities of the melt produced in amphibolite at temperature higher than 850℃ are on a level with 104.Pa·s. The interconnected melt with such a viscosity may segregate from the source rock and form the magma over reasonable geological time. Therefore, it is believed that at the lower part of the overthickened crust, the tonlitic and grano-dioritic magma may be generated through the dehydration melting of amphibolite.

关键词： solid amphibolite, high pressure, high temperature, time, partial melting.

The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, china

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Science china Earth sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3 & WANG Lei2.1. Institute of Tibetan Plateau Research, chinese academy of sciences, beijing 100085,{2. 2. Faculty of Earth sciences and Mineral Resources,{2. University of Geosciences, beijing 100083,{2. 3. Tianjin Institute of geology and Mineral Resources, Tianjin 300170,{2. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Faculty of Earth sciences and Mineral Resources China University of Geosciences Beijing China Tianjin Institute of geology and Mineral Resources Tianjin China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

A new method for spatio-temporal prediction of rainfall-induced landslide

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Science china Earth sciences 2006年第4期49卷 421-430页

作者： DING Jixin1,2. YANG Zhifa2. SHANG Yanjun2. ZHOU Shenghua1 & YIN Juntao3 1. china Non-ferrous Metals Resource Geological Survey, beijing 100012. china 2. Institute of geology and {4., chinese academy of sciences, Key Laboratory of Engineering Geomechanics, beijing 10002., china 3. School of Geoscience & Environmental Engineering, Central South University, Changsha 4.0083, china china Non-ferrous Metals Resource Geological Survey Beijing China Institute of geology and geophysics Chinese Academy of Sciences Key Laboratory of Engineering Geomechanics Beijing China School of Geoscience & Environmental Engineering Central South University Changsha China

Geological condition and rainfall are two most principal conditions inducing landslides in the Chongqing region. By analyzing the forming conditions of rainfall-induced landslides, a new method for spatio-temporal prediction of rainfall-induced landslide is brought forward on the basis of grading and overlapping geological condition and rainfall factor in this paper. At first, semi-quantitative assessment and grading for the geological condition of a certain area or slope can be carried out with the multi-factor interactive matrix. Then the severity of rainfall in that area is grading according to the maximum daily rainfall and the total rainfall in a rainfall course. Finally, the “landslide probability judgement factor” can be worked out through grading and overlapping “geological condition influenc- ing factor” and “rainfall influencing factor”, by which the landslide can be graded into 4.grades, they are landslide extremely easily happening, landslide easily happening, landslide difficultly happening and landslide hardly ever happening respectively. More accurate spatio-temporal prediction of rain- fall-induced landslides can come true on the ground of detailed geological survey of some dangerous slopes in an area and more precise weather forecast. Finally, the reliability and feasibility of carrying out the spatio-temporal prediction of rainfall-induced landslides with the method of “two factors” grading and overlapping are validated by the example of Jipazi landslide.

关键词： rainfall-induced landslide, geological condition, rainfall, two factors, grading and overlapping, interactive matrix, spatio-temporal prediction.