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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 {2., Beijing 100012. china 2. institute of geology and Geophysics, Chinese Academy of Sciences, Key Laboratory of Engineering Geomechanics, Beijing 10002., china 3. School of Geoscience & Environmental Engineering, Central South University, Changsha 410083, china china Non-ferrous Metals Resource geological {2. 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.

Numerical　modeling　of　radionuclide　migration　in　porous　media　with　nonequilibrium　sorption

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Journal of Environmental Sciences 1996年第1期8卷 86-93页

作者： Chen Jiajun Dai Jie(Department of Environmental Engineering,Tsinghua University,Beijing 100084,china)(tianjin {2. of geological Investigation and Research,tianjin 300191,china)Xu Zhaoyi Tian Kaiming(Changchun University of Earth Sciences,Changchun 1

When radionuclides migrate in porous media with water serving as carrier, the mechanism of sorption and desorption is not negligible. nonequilibrium conditions exist in sorption and desorption. In this paper,a numerical model of radionuclide migration with nonequilibrium sorption was *** algorithm of numerical descretizing and direct substituting was adopted in coupling of the convective-dispersive equation and the nonequilibrium sorption isotherm in this model ,and this makes it easier to solve the model numerically.A quantitative analysis is made for the first time that the influence of nonequilibrium sorption, represented by the rate coefficient which shows how quickly the nonequilibrium condition in sorption and desorption reaches equilibrium on the migration of radionuclide,and results show that it affects the migration perceptibly. Finally the model was verified by using the observed data of radionuclide migration test conducted in the field, and which clarified its availability.

关键词： adionuclide migration sorption and desorption nonequilibrium sorption rate coefficient.

Metallogenic geochemistry of Sb-mineralization in southern margin of North china platform

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Chinese Science Bulletin 1999年第S2期44卷 17-18页

作者： YANG Xiaoyong~1, YANG Xueming~1, ZHANG Jianjun~2. CAO Gaoshe~2.and ZHANG Zhengwei~2.1. Department of Earth and Space Sciences, University of Science and Technlogy of china, Hefei 2.002., china 2. {2. of geology, Henan Bureau of geology and mineral resources, Zhengzhou 450053, china Department of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China institute of geology Henan Bureau of Geology and Mineral Resources Zhengzhou 450053 China

1 geological setting THE Sb mineralization zone in the south margin of North{2. platform is located in the transitional edgeof North{2. plate and Yangtze plate, belonging to Qinling fold system, whose tectonic line is inNWW-SEE direction regionally. Because of the huge compression caused by the collision of the twoplates, the rocks undergone strong deformation and metamorphism have very complicated structures. Theregional deep fault-Shuanghuaishu fault-controls Sb-mineralization zone belt, and all the Sb-oredeposits or mineralized spots appear alone at the very southern margin of the fault. The lithostragraphirunits in the mineralized zone are relatively simple, mainly composed of Jiebei Group （Pt2./sub>J2./sup>） of QinglingFormation （with middle-high metamorphsim） and the upper Triassic system （with little metamorphism）.

关键词： Sb-mineralization metallognic geochemistry North china plateform.

Geochronological evidence of Indosinian(high-pressure) metamorphic event and its tectonic significance in Taxkorgan area of the Western Kunlun Mountains,NW china

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Science china Earth Sciences 2010年第10期53卷 1445-1459页

作者： YANG WenQiang1,LIU Liang1,CAO YuTing1,WANG Chao1,2.HE ShiPing2.LI RongShe2.& ZHU XiaoHui1 1 State Key Laboratory of Continental Dynamics,Department of geology,Northwest University,Xi’an 710069,china 2.Xi’an {2. of geology and mineral Resource,Xi’an 710054,china State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an China Xi’an institute of geology and {2. Resource Xi’an China

The CL images,LA-ICP-MS in situ trace elements analysis,and U-Pb dating for zircons indicate that the metamorphic ages of the sillimanite-garnet-biotite gneiss and the garnet-amphibole gneiss from eastern Taxkorgan of the Western Kunlun Mountains are 2.0±2.and 2.0±3 Ma respectively,and their protolith ages are younger than 2.3±2.and 480±8 Ma *** samples were collected at the same outcrops with HP mafic granulite and HP pelitic *** assemblage of the sillimanite-garnet-biotite gneiss(Grt+Sill+Per+Q) is consistent with that of HP pelitic granulite at early high amphibolite-granulite facies *** assemblage of the garnet-amphibole gneiss(Grt+Amp+Pl+Q) is consistent with retro-metamorphic assemblage of HP mafic granulite at amphibolite facies *** dating results suggest that these HP granulites underwent peak metamorphism at 2.0±2.to 2.3±2.***,the Kangxiwar tectonic zone was probably formed by subduction and collision of the Paleo-Tethys Ocean during *** ages of the two samples,together with previously published U-Pb zircon dating age,suggest that the sillimanite-garnet schist-quartzite unit is a late Paleozoic unit,not a part of the Paleoproterozoic Bulunkuole Group.

关键词： Western Kunlun Mountains LA-ICP-MS zircon dating Bulunkuole Group Indosinian Kangxiwar tectonic zone

SHRIMP Zircon U-Pb Ages and Geochemical Characteristics of the Neoproterozoic Granitoids in the Huangling Anticline and Its Tectonic Setting

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Journal of Earth Science 2012年第5期23卷 659-675页

作者：魏运许彭松柏蒋幸福彭中勤彭练红李志宏周鹏曾雄伟 Wuhan institute of geology and {2.s resources Wuhan Center of Geological Survey Faculty of Earth Sciences China University of Geosciences Three Gorges Research Center for Geo-hazard Ministry of EducationChina University of Geosciences State Key Laboratory of geological Processes and mineral {2. China University of Geosciences

SHRIMP zircon U-Pb dating of the Neoproterozoic Maoping （茅坪） series （Sandouping （三斗坪） rock suite） granites exposed in the southern part of the Huangling （黄陵） anticline shows that the formation time of Sandouping biotite-hornblende tonalite intrusion, Jinpansi （金盘寺） hornblende-biotite tonalite intrusion, and Longtanping （龙潭坪） monzogranite are 863±9, 842.10, and 844±10 Ma, respectively. Their geochemical features include A/CNK=0.98-1.06, from metaluminous to weakly peraluminous, δ=1.37-1.53, Sm/Nd=0.17-0.2., and RbN/YbN=1.1-3.62. These indicate that the granite rocks are supersaturated SiO2.calc-alkaline granitoids. The characteristic of Sr-Nd isotopic composition is that the values of εNd（t） and εsr（t） are -12.4 to -11.0 and 2..2.32.2. respectively. It also suggests that the material source of the granite rocks mainly originated from the crust, and they formed in a volcanic arc tectonic environment. These facts suggest that the occurrence of Neoproterozoic granitoids in the southern part of the Huangling anticline should be related to an arc environment along an active continental margin caused by southward subduction of oceanic crust beneath the northern Yangtze craton, and the formation age is not later than 863 Ma.

关键词： Huangling anticline Yangtze plate Neoproterozoic granitoid SHRIMP zircon U-Pbdating geochemistry tectonic setting.

U-Pb dating of zircon from the bed parallel anatectic granitic intrusion in the Baoban group in Hainan Island and the tectonic implication

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Science china Earth Sciences 2005年第12期48卷 2092-2103页

作者： DING Shijiang1, HU Jianmin2. SONG Biao3,4, CHEN Mulun1, XIE Shengzhou1 & FAN Yuan1 1. geological surveying {2. of Hainan, Haikou 5702.6, china 2. {2. of Geomechanics, Chinese Academy of geological Sciences, Beijing 100081, china 3. Beijing Center of SHRIMP, Beijing 100037, china 4. {2. of geology, Chinese Academy of geological Sciences, Beijing 100037, china geological surveying {2. of Hainan Haikou China institute of Geomechanics Chinese Academy of Geological Sciences Beijing China Beijing Center of SHRIMP Beijing China institute of geology Chinese Academy of Geological Sciences Beijing China

The petrological and geochemical features of the bed parallel granitic intrusion in the Pre-Cambrian Baoban group in Hainan Island attest to the anatexis origin of the granites. U-Pb dating analyses of zircons from the anatectic granite and the biotite two-feldspar gneiss in the Baoban group, using SHRIMP II in the Beijing Ion-probe Center, acquire 2.6Pb/2.8U ages of 368±3.5 Ma (of granite, 95% confidence level, MSDW=1.2.) and 362.9±6.1 Ma (of gneiss, 95% confidence level, MSDW = 2.04) respectively. The two late Devonian ages indicate consistently a tectonic- thermal event experienced in Hainan Island, and are the first discovered record of the Devonian geological process in the district. This event possibly resulted from the deep ther-mal-dynamic process when the Gondwana continent began to break up in the Devonian period.

关键词： Hainan Island, Devonian period, anatectic granite, zircon SHRIMP U-Pb dating.

Metallogenic characteristics of epithermal gold deposits in Tianshan, Xinjiang, china

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Chinese Science Bulletin 1999年第S2期44卷 138-139页

作者： FENG Jianzhong~1, FU Shuixing~2. WU Dewen~3 and YANG Zian~3 1. Department of geology, Peking University, Beijing 100871, china 2. Beijing {2. of geology for mineral resources, Beijing 100012. china 3. Center of Remote Sensing for geology, CNNC, Beijing 101601, china Department of geology Peking University Beijing 100871 China Beijing institute of geology for {2. resources Beijing 100012 China Center of Remote Sensing for geology CNNC Beijing 101601 China

TIANSHAN in southern Xinjiang belongs to the Paleozoic island arc system in which volcanic rocks are extensively distributed. A series of epithermal gold deposits such as the Axi, Xitan, Cuiling andShuangfengshan gold deposits have been discovered. 1 geological settings of epithermal gold deposits in Tianshan, southern Xinjiang Tianshan in southern Xinjiang belongs to the Paleozoic island arc system. To its north is the Kazakhstan plate, and to its north is the Tarim plate. From west to east, the tectonic units are characterizedby Yili island arc, southern Tianshan arc-basin, Jiaoluotage island arc and Xingxingxia island arc. TheEW-trending Tianshan ore belt is controlled by Kanggurtag geosuture. In its west part, it is controlled byShenglidaban geosuture. The linear structure is NNW-trending; from north to south, the faults

关键词： metallogenic characteristics gold deposits Tianshan Xinjiang.

DISCUSSION ON THE NAMING OF QUATERNARY TRANSGRESSIONS IN WEST-SOUTHERN COAST PLAIN OF BOHAI SEA

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Acta Oceanologica Sinica 1987年第1期6卷 104-115页

作者：王强李凤林李玉德高秀林 tianjin institute of {2. and mineral resources tianjin geology and mineral {2. Bureau Shandong Province Dezhou Department of Geography tianjin Teachers University

Based on micropalaeontological information of over 150 drill holes, this paper discusses the problem on the naming of Quaternary transgressions in the west-southern coast plain of Bohai Sea. We consider that palaeotide and sedimentation have a great influence on the distribution of micropalaeontological fossils. In view of the present technical level, it is necessary for transgression sequence to be established under the following conditions: full evidence of fossils; clear climate; and stable sedimentary beds. In establishing a transgression, its contents of time and phase concept must be proposed, and its biofacies, sedimentary facies and palaeoclimatology must be analysed synthetically.

关键词： DISCUSSION ON THE NAMING OF QUATERNARY TRANSGRESSIONS IN WEST-SOUTHERN COAST PLAIN OF BOHAI SEA

Oxygen isotope as a tracer of REE fractionation in water-rock interaction

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Chinese Science Bulletin 1999年第S2期44卷 224-226页

作者： DENG Hailin~1, LI Chaoyang~1, ZHOU Yunman~2.and WANG Chongwu~2.1. Open Laboratory of Ore Deposit Geochemistry, institute of Geochemistry Chinese Academy of Sciences, Guiyang 550002. china 2. No.1 {2. Party, Yunnan Bureau of geology and mineral resources, Xundian 6552.5, china Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China No. 1 geological Party Yunnan Bureau of Geology and Mineral Resources Xundian 655205 China

STABLE oxygen isotope is not only an effective approach to tracing water-rock interactions, but also canprovide much information about ore-forming temperature and source and evolution of ore fluids in thestudy of hydrothermal deposits. The rare-earth elements (REE) can be used to trace the sources ofore-forming materials and can also, to some extent, indicate the physical and chemical properties of fluids in the geochemical processes. The combination of these two aspects of research can effectivelyprobe into the geochemical behavior and evolution of REE in the process of water-rock interaction duringhydrothermal ore deposition. On the other hand, the essence of REE as tracers in hydrothermal mineralization can be better understood. In this note the Lemachang independent Ag deposit in northeastern Yunnan is selected for a case study.

关键词： oxygen isotope tracer water-rock interaction REE fractionation.