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Science china Earth sciences 2004年第9期47卷 794-803页

作者： ZHANG Yueqiao1, CHEN Wen2. 3.& YANG Nong1 1. institute of geomechanics, {2. academy of Geological sciences, Beijing 100081, china 2. institute of geology, {2. academy of Geological sciences, Beijing 10003., china 3. institute of geology and geophysics, chinese academy of sciences, Beijing 100029, china institute of geomechanics Chinese Academy of Geological Sciences Beijing China institute of geology Chinese Academy of Geological Sciences Beijing China institute of geology and {2. Chinese Academy of Sciences Beijing China

Based on field geological survey, structural measurements and classical Ar/Ar dating of mica, biotite and K-feldspar, we obtain cooling ages for Miocene left-lateral shear along the Xianshuihe fault zone. The results document two thermal events during the sinistral shear. The early event (12.10 Ma) corresponds to rapid cooling of the Zheduoshan granitic massif from above 700℃ to below 3.0℃. The late event (5-3.5 Ma) corresponds to cooling of granites intruded along the eastern side of the fault zone. These dating results provide important thermochronological constraint on the timing of late Cenozoic eastward extrusion of the Chuan-Dian Block in the SE Tibetan margin.

关键词： Xianshuihe fault zone, Zheduoshan granitic massif, sinistral shear deformation, 40Ar/3.Ar dating, late Cenozoic.

Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

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Science china Earth sciences 2006年第7期49卷 731-738页

作者： QIAO Yansong1,3. GUO Zhengtang2.1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & LIU Tungsheng1 1. institute of geology and {2., chinese academy of sciences, Beijing 100029, china 2. institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 3. institute of geomechanics, {13. {12. of Geological sciences, Beijing 100081, china institute of geology and {2. Chinese Academy of Sciences Beijing China institute of geomechanics Chinese Academy of Geological Sciences Beijing China institute of Earth Environment Chinese Academy of Sciences Xi’an China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 2.3.1 m sequence varies from 6 to 13.μm and the > 63.μm fraction representsonly 5.3. in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

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.{3. Non-ferrous Metals Resource Geological Survey, Beijing 100012.{3. {2., chinese academy of sciences, key laboratory of engineering geomechanics, Beijing 100029,{3. 3. School of Geoscience & Environmental engineering, Central South University, Changsha 410083.{3. china Non-ferrous Metals Resource Geological Survey Beijing China institute of geology and {2. 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.

Petrology and mineral chemistry of new ureilites found in Grove Mountains, Antarctica

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Progress in Natural Science:Materials International 2008年第4期18卷 431-439页

作者： Bingkui Miaoa,b,, Yangting Linb, Guiqin Wangc, Daode Wangc, Ziyuan Ouyangd a key laboratory of Geological {2. Center of Guangxi Province, Guilin University of Technology, Guilin 541004,{3. b State key laboratory of Lithospheric Evolution, institute of geology and geophysics, chinese academy of sciences, Beijing 100029,{3. c key laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640,{3.d National Astronomical Observatories, chinese academy of sciences, Beijing 100012.{3. key laboratory of Geological {2. Center of Guangxi Province Guilin University of Technology Guilin 541004 China State key laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China key laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Petrography and mineral chemistry of two new ureilites, GRV 02.512.and 02.93., from the Grove Mountains, Antarctica, are reported in this paper. GRV 02.512.exhibits a typical ureilite texture, and consists of 48.3. olivine, 9.4% pigeonite and 3..1% carbo- naceous interstitial material and/or reduction product. GRV 02.93. has a cataclastic porphyritic texture, and consists of 19.1% olivine and 14.1% pigeonite embedded in 66.3. carbonaceous interstitial material and/or reduction product. The coarse-grained olivine and pigeonite in both meteorites have homogeneous cores, and they are FeO-rich within the range of the ferroan subgroup (subgroup I) of olivine-pigeonite ureilites. All olivine grains of the meteorites show reduction zones along boundaries and cracks. Abundant diamond coexists with graphite as graphite-rich patches and veins in the carbonaceous interstitial material. Petrogenesis of both meteorites and the origin of diamond are discussed.

关键词： Meteorite Achondrite Ureilite Diamond Antarctica

Rainfall-induced landslide stability analysis in response to transient pore pressure——A case study of natural terrain landslide in Hong Kong

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Science china(Technological sciences) 2003年第Z1期46卷 52-68页

作者： LAN Hengxing, ZHOU Chenghu C. F. LeeWANG Sijing & WU Faquan State key laboratory of Natural Resources and Environmental System, {2. of Geographical Sci-ences and Natural Resources Research,{3., Beijing 100101, china Department of Civil engineering, Hong Kong University, Hong Kong, china 3. {2. of geology and geophysics,{3., Beijing 100029, china chinese Acad Sci State Key Lab Nat Resources & Environm Syst Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Univ Hong Kong Dept Civil Engn Hong Kong Hong Kong Peoples R China chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Transient pore pressure in response to short intense rainfall process plays an important role in shallow landslide occurrence. Using GIS technology, we carry out the rainfall-induced landslide stability analysis in response to transient pore pressure by means of transient and unsaturated rainfall infiltration modeling. A case study is performed on the shallow landslide stability analysis in Hong Kong. Detailed analysis and discussion reached some useful conclusions on the tempo-spatial behavior and characteristics of slope stability response and pore pressure response to typical rainfall process. Comparison analysis is performed on some important issues including landslide stability response in different types of slopes with different hydraulic properties, antecedent rainfall and landslide stability, and the nature of pore pressure response time. These studies might give us an important insight into landslide tringgering mechanism and the hydrological process in response to rainfall, and provide systematic information and evidences for effective risk assessment and warning system establishment.

关键词： rainfall-induced landslide, transient pore pressure, landslide stability in response to rainfall, GIS.

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of Mineral Resources Exploration , chinese academy of sciences , Beijing 100101, china 2. {2. of geology , chinese academy of sciences , Beijing 100029, china 3. {2. of High Energy Physics , chinese academy of sciences , Beijing 100817 , china 4. Beijing University of Science and engineering , Beijing 100083. china Corresponding author The Research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China institute of geology Chinese Academy of Sciences Beijing China institute of High Energy Physics Chinese Academy of Sciences Beijing China Beijing University of Science and engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

A coupled elasto-plastic-damage mechanical model for marble

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Science china(Technological sciences) 2011年第S1期54卷 228-234页

作者： ZHOU Hui 1,ZHANG Kai 2.& FENG XiaTing 1 1 State key laboratory of {2. and Geotechnical engineering,institute of Rock and Soil Mechanics,chinese academy of sciences,Wuhan 43.071,china 2.State key laboratory for {2. and Deep Underground engineering,china University of Mining&Technology,Xuzhou 2.1008,china State key laboratory of {2. and Geotechnical {3. Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan China State key laboratory for {2. and Deep Underground {3. China University of Mining & Technology Xuzhou China

A profound understanding of the mechanical behaviors of marble is very important for the design and construction of deep diversion tunnels in Jinping II hydropower *** this paper,a coupled elasto-plastic-damage mechanical model is presented for Jinping ***,the experimental investigations on Jinping marble are ***,based on the framework of continuum damage and plastic theories,a general mechanical model is proposed to predict the mechanical responses of Jinping *** proposed model is used to simulate the triaxial compressive tests,and there is a general good agreement between experimental data and numerical predictions in a qualitative *** proposed model is able to capture the main features of Jinping marble observed in experiments,such as progressive yielding process,damage induced by plastic distortion,dilation,elastic degradation and stress sensitivity.

关键词： mechanical model damage elasto-plastic coupling marble

Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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Science china Earth sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2. TONG Jinnan3. QIU Haiou4 & ZHAO Laishi3.1. Nanjing institute of geology and Palaeontology,{2., Nanjing 2.0008, china 2. Henan institute of Geological Survey, Zhengzhou 450007, china 3. State key laboratory of Geological Processes and Mineral Resources at china University of Geosciences, Wuhan 43.074, china 4. Faculty of Material sciences and Chemical {12., china University of Geosciences, Wuhan 43.074, china Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing China Henan institute of Geological Survey Zhengzhou China State key laboratory of Geological Processes and Mineral Resources at{2. University of Geo{3. Wuhan China Faculty of Material sciences and Chemical engineering China University of Geosciences Wuhan China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13. background values are intensively controlled by palaeogeographic environment. In general, δ 13. values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

3. thermo-hydro-mechanical-migratory coupling model and FEM analyses for dual-porosity medium

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Science china(Technological sciences) 2010年第8期53卷 2172-2182页

作者： ZHANG YuJun 1&ZHANG WeiQing 2.1 State key laboratory of {2. and Geotechnical engineering,institute of Rock and Soil Mechanics, chinese academy of sciences,Wuhan 43.071,china 2.chool of Civil engineering,Southwest Jiaotong University,Chengdu 61003.,china State key laboratory of {2. and Geotechnical {3. Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan China School of Civil engineering Southwest Jiaotong University Chengdu China

One kind of 3. coupled thermo-hydro-mechanical-migratory model for saturated-unsaturated dual-porosity medium was established,in which the stress field and the temperature field are single,but the seepage field and the concentration field are double,and the influences of sets,spaces,angles,continuity ratios,stiffness of fractures on the constitutive relationship of the medium can be *** relative three-dimensional program of finite element method was also *** comparing with the existing computation example,reliability of the model and the program were *** a hypothetical nuclear waste repository as a calculation example,the radioactive nuclide leak was simulated numerically with both the rock mass and the buffer being unsaturated media,and the temperatures,negative pore pressures,flow velocities,nuclide concentrations and normal stresses in the rock mass were *** results showed that the temperatures,negative pore pressures and nuclide concentrations in the buffer all present nonlinear changes and distributions that even though the saturation degree in porosity is only about 1/9 of that in fracture,the flow velocity of underground water in fracture is about 6 times of that in porosity because the permeability coefficient of fracture is almost four orders higher than that of porosity,and that the regions of stress concentration occur at the vicinity of two sides of the boundary between buffer and disposal pit wall.

关键词： dual-porosity medium thermo-hydro-mechanical-migratory coupling three-dimensional model FEM analysis

General regularity of dynamic responses of slopes under dynamic input

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Science china(Technological sciences) 2003年第Z1期46卷 120-132页

作者： QI Shengwen, WU Faquan & SUN Jinzhong institute of geology and {2.,{3., Beijing 100029, china College of engineering Technique, china University of Geosciences, Beijing 100083. china chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China china Univ Geosci Coll Engn Techn Beijing 100083 Peoples R China

Through lots of numerical simulations with FLAC3., dynamic responses of slopes are comprehensively studied in this paper and the general regularities of the isoline of the coefficient of the displacement, velocity and acceleration of the slope section are reached. Given a certain material slope, if the height of the slope is less than a certain value, the displacement, velocity and acceleration linearly enlarge with elevation in the vertical direction; if the height of the slope surpasses the certain value, the displacement,velocity and acceleration do not linearly enlarge with elevation any more, on the other hand, they fluctuate with a certain rhythm. At the same time, the rhythm appears in the horizontal direction, and the displacement, velocity and acceleration of the slope surface enlarge near the slope surface. The distribution form of the isoline of the coefficient of displacement, velocity and acceleration in the section of the slope is remarkably affected by the slope angle. In the certain area near the slope surface, the isoline of displacement,velocity and acceleration is parallel to the surface of the slope; in the mean time the strike direction of the extremum area is parallel to the surface of the slope, too. The charts of the slope dynamic responses can be depicted with two indexes, one is the strike direction of the isoline, and the other is the number of the rhythm extremum area of the direction parallel to the surface of the slope.

关键词： slope, dynamic response, regularity, rhythm.