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Journal of Mountain Science 2010年第3期7卷 226-233页

作者： LI Yanfu wang Zhaoyin shi Wenjing wang Xuzhao State Key Laboratory of Hydroscienee and engineering Tsinghua University Beijing 100084 China beijing institute of geology for Mineral Resources Beijing 100012 China

Avalanches and landslides,induced by the Wenchuan Earthquake on May 12,2008,resulted in a lot of disaggregated,solid material on slopes that could be readily mobilized as source material for debris *** triggered numerous slope debris flows with great damage to highways and rivers over the subsequent two *** debris flows(as opposed to channelized debris flows) are defined as phenomena in which high-concentration mixtures of debris and water flow down slopes for short distances to highways and river *** on field investigations and measurements of 19 slope debris flows,their main characteristics and potential mitigation strategies were *** rainfall intensity is the main triggering *** rainfall intensities for simultaneous occurrence of single,several and numerous slope debris flow events were 20 mm/day,30mm/day,and 90 mm/day,*** investigations also revealed that slope debris flows consist of high concentrations of cobbles,boulders and *** are two-phase debris *** liquid phase plays the role of lubrication instead of transporting *** particles collide with each other and consume a lot of *** velocities of slope debris flows are very low,and their transport distances are only several tens of *** debris flows may be controlled by construction of drainage systems and by reforestation.

关键词： Slope debris flow rainfall intensity Wenchuan Earthquake landslide avalanche

Integral ear elimination and virtual point-based updating algorithms for constrained delaunay TIN

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Science china(Technological sciences) 2008年第S1期51卷 135-144页

作者： WU LiXin1,2,wang YanBing2,3 & shi WenZhong2,4 1 institute for Geo-informatics & Digital Mine Research,Northeastern university,Shenyang 110004,china 2 institute for GIS/RS/GPS & Subsidence engineering Research,china university of mining & technology,beijing 100085,china 3 Laboratory of 3D Information Acquisition & Application,Capital Normal university,beijing 100037,china 4 Center for Advanced GIS Research,LSGI,Polytechnic university Hong Kong,Hong Kong,china Northeastern Univ Inst Geoinformat & Digital Mine Res Shenyang 110004 Peoples R China china Univ mining & Technol Inst GIS RS GPS & Subsidence Engn Res Beijing 100085 Peoples R China Capital Normal Univ Lab Informat Acquisit & Applicat Beijing 100037 Peoples R China Hong Kong Polytech Univ LSGI Ctr Adv GIS Res Hong Kong Hong Kong Peoples R China

Constrained delaunay Triangular Irregular Networks (CD-TIN),a kind of special data structure,have many practical applications in Geoinformatics,especially in the representation of linear constrained triangulation for DTM and DSM,such as in digital city and digital mine. Past researches on D-TIN mainly focused on point in-sertion and deletion without consideration of constraint,and that on CD-TIN usu-ally paid more attention to the insertion algorithms for points and edges,but little to the deletion algorithms. The presented algorithms are far insufficient for the dy-namic updating of CD-TIN. In this paper,the constraint edge in CD-TIN is consid-ered to be any set of broken lines,i.e.,polygon edges,broken lines and simple segments. The constraint edge may be composed of one or more constraint seg-ments,and it is allowed to be in any form: Open or close,intersection or self-in-tersection. By improving to present insertion and deletion algorithms for D-TIN,two new algorithms for CD-TIN updating are presented. According to the polymorphism of the constraints in CD-TIN,virtual point is adopted to represent the crossing node between constraint edges when a constraint edge is inserted in CD-TIN. Two new algorithms named as Integral Ear Elimination (IEE) and Influence Domain Retrian-gulation for Virtual Point (IDRVP) are presented,the former is for constraint point deletion,while the later is for the insertion and deletion of constraint edge. The principle of IDRVP is that to divide the influence domain of a virtual point into some parts by the constraint-keeping edges,and to retriangulate each part of the influ-ence domain individually referring to the constraint visible property and constraint empty circle (CEC) criterion. Finally,a prototype system is developed with VC++,one case on the integration of 3D terrain and buildings is demonstrated to test the correctness of new algorithms. It shows that the new algorithms are effective for the updating of CD-TIN.

关键词： delaunay TIN spatial constraint data updating spatial modeling polymorphism digital mine

Characteristics and genesis of groundwater salinization in coastal areas of the Lower Reaches of Oujiang Basin

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Journal of Groundwater Science and engineering 2024年第2期12卷 190-204页

作者： Mei-hui Zhang shi-yang Zhou Dan-dan Liu ying Zhang Yu-xi Zhang Xi Chen Hui-wei wang Bei Li Wei Kang Bing yi Wan-peng shi institute of Hydrogeology and Environmental geology Chinese Academy of Geological SciencesShijiazhuang 050061China Fujian Provincial Key Laboratory of Water Cycling and Eco–Geological Processes Xiamen 361021FujianChina china university of Geosciences(beijing) Beijing 100083China Changsha Center of Natural Resources Comprehensive Survey China Geological SurveyChangsha 410600China Hydrogeological Environmental Geological Survey Center of china Geological Survey Tianjin 071501China china university of Geosciences Wuhan 430074China

The coastal areas of the lower reaches of Oujiang River Basin are rich in groundwater ***,the unsustainable exploitation and utilization of groundwater have led to significant changes in the groundwater *** the characteristics and genesis of groundwater salinization is crucial for preventing its deterioration and ensuring sustainable *** this study,a comprehensive approach combining the ion ratio method,mineral saturation index method and multivariate statistical analysis was employed to investigate the hydrochemical characteristics and main controlling factors in the study *** findings reveal that:(1)Groundwater samples in study area exhibit a neutral to slightly alkaline *** predominant chemical types of unconfined water are HCO_(3)-Ca·Na,HCO_(3)·Cl-Na·Ca and HCO_(3)·SO_(4)-Ca·Na,while confined water mainly exhibits Cl·HCO_(3)-Na and Cl-Na types.(2)Salinity coefficients indicate an increase in salinity from unconfined to confined ***,Na^(+)and Cl^(–)concentrations show an increasing trend from mountainous to coastal areas in unconfined water,while confined water displays variability in TDS,Na^(+)and Cl^(–)concentrations.(3)Groundwater salinity is mainly influenced by water-rock interactions,including the dissolution of halite and gypsum,cation exchange,and seawater intrusion ***,human activities and carbonate dissolution contribute to salinity in unconfined *** intrusion is identified as the primary factor leading to higher salinity in confined water compared to unconfined water,with increasing cation exchange and seawater interaction observed from unconfined to confined water.

关键词： Hydrochemical Multivariate statistical analysis Seawater intrusion

Feasibility study of highwall mining in north surface mine of yima Coal Corporation,china

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Feasibility study of highwall mining in north surface mine o...

A semi-analytical pressure and rate transient analysis model for inner boundary and propped fractures exhibiting dynamic behavior under long-term production conditions

中国科学院地质与地球物理研究所2003学术年会

作者： Guoming Cheng~(1)),Sijing wang~(1)),and Meifeng Cai~(2)) 1) institute of geology and geophysics,chinese academy of sciences,beijing 100029.china 2) Civil and Environmental engineering School.university of Science and technology beijing.beijing 100083.china

yima Coal Corporation is considering to adopt highwall mining method with auger machine to recover coal from north surface pit that has reached final highwall *** major geomechanical issues associated with auger mining are highwall and pillar *** on the field investigation and laboratory test results of mechanical parameters,numerical modeling is carried out to assess the stability of highwall and *** measurements of highwall deformation have been used to validate and ensure the confidence for the development of realistic *** results of numerical modeling show that the mining method is feasible for mining the seam of 10 m thickness in north surface coal mine.

关键词： highwall mining surface mine stability evaluation feasibility study

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Petroleum Science 2024年第4期21卷 2520-2535页

作者： Lin-Song Cheng Chong Cao Quan-Yu Pan Pin Jia Ren-yi Cao Zhi-Kai wang Jun-Jie shi College of Petroleum engineering China University of Petroleum (Beijing) Sinopec Petroleum Exploration and Production Research institute CNOOC Research institute State Key Laboratory of Water Resources Protection and Utilization in Coal mining

The loss of hydrocarbon production caused by the dynamic behavior of the inner boundary and propped fractures under long-term production conditions has been widely reported in recent studies. However,the quantitative relationships for the variations of the inner boundary and propped fractures have not been determined and incorporated in the semi-analytical models for the pressure and rate transient analysis. This work focuses on describing the variations of the inner boundary and propped fractures and capturing the typical characteristics from the pressure transient curves.A generalized semi-analytical model was developed to characterize the dynamic behavior of the inner boundary and propped fractures under long-term production conditions. The pressure-dependent length shrinkage coefficients, which quantify the length changes of the inner zone and propped fractures, are modified and incorporated into this multi-zone semi-analytical model. With simultaneous numerical iterations and numerical inversions in Laplace and real-time space, the transient solutions to pressure and rate behavior are determined in just a few seconds. The dynamic behavior of the inner boundary and propped fractures on transient pressure curves is divided into five periods: fracture bilinear flow(FR1),dynamic PFs flow(FR2), inner-area linear flow(FR3), dynamic inner boundary flow(FR4), and outer-area dominated linear flow(FR5). The early hump during FR2 period and a positive upward shift during FR4period are captured on the log-log pressure transient curves, reflecting the dynamic behavior of the inner boundary and propped fractures during the long-term production *** transient pressure behavior will exhibit greater positive upward trend and the flow rate will be lower with the shrinkage of the inner boundary. The pressure derivative curve will be upward earlier as the inner boundary shrinks more rapidly. The lower permeability caused by the closure of un-propped fractures in the inner zo

关键词： Semi-analytical model Length shrinkage Dynamic behavior Boundary changes Transient behavior

Stratigraphic framework and sedimentary evolution during the Cryogenian-Ediacaran transition in northeastern Sichuan Basin,South china

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Petroleum Science 2024年第2期21卷 823-835页

作者： yi Zhang Hong-Wei Kuang Yong-Qing Liu Qiang shi Dong-Ge wang Ke-Ning Qi Yu-Chong wang Da-Wei Qiao Xiao-Shuai Chen Li-Zhi Wu Meng Tian Long Chen yi Wei Liao-Yuan Song Jian Li Zi-Gang Wu yun-Qian Liu Xuan-Chun Liu An-Qing Chen Zhi-Wei Liao institute of geology Chinese Academy of Geological SciencesBeijing100037China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing400044China No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing401121China Chongqing institute of Geological Survey Chongqing401122China Key Laboratory of deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu610059SichuanChina

The northeastern Sichuan area in the northern yangtze margin has unique Ediacaran geological records,especially the Doushantuo Formation(DST),and become a hot research area in recent ***,the Cryogenian-Ediacaran(C-E)boundary has not been precisely identified,which restricts the in-depth study of geological information during this crucial transitional period and is unfavorable for a systematic and complete understanding of the yangtze Block and even the global paleogeographic *** study conducted stratigraphy,sedimentology,and chronostratigraphy to establish the stratigraphic framework and sedimentary evolution of the C-E transition strata in northeastern *** results showed that the Ediacaran sediments,without the cap dolomite,unconformably overlaid the Cryogenian sediments in the studied *** Member II of the DST,characterized by 50-160 m of red-green sandstone(approximately equivalent to the original Chengkou“Guanyinya Formation”),directly overlaid the Cryogenian sediments and displayed a 623±2.3 Ma maximum depositional age from the detrital zircon U-Pb *** stratigraphic correlations indicate that the C-E transition strata in northeastern Sichuan had a consistent lithological association and sedimentary sequence characteristics but differed from the Three ***,the upper Nantuo massive glacial diamictites transition to the icebergs rafted lonestone-bearing mudstones at the top,then change upward to DST barrier coast *** proposed DST of the northeastern Sichuan Basin was divided into three lithostratigraphic members without the regional Member I cap dolomite:(i)Member II purple-red,gray-green sandstone strata,(ii)MemberⅢblack mudstone strata,and(iii)Member IV P-Mn bearing *** the C-E transition,the study area experienced(i)the global deglaciation stage in the terminal Marinoan glaciation and(ii)the filling-leveling up stage with clastic rocks in the early ***,the early Ediacaran

关键词： Marinoan glaciation Doushantuo formation Cap dolomite deglacial and coastal deposits detrital zircon U-Pb dating

Exhumation of the Dabie UHP Terrane,china

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Exhumation of the Dabie UHP Terrane,China

Linux下基于体绘制算法实现地震数据的三维可视化

中国科学院地质与地球物理研究所2008学术年会

作者： wang Qingchen,~1 State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics,chinese academy of sciences, beijing 100029,china shi Yonghong, department of geology,School of Resource and Environment engineering,Hefei university of technology,Hefei 230009,china Lin Wei,and Guo Jinghui State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics,chinese academy of sciences, beijing 100029,china

Exhumation of deeply buried ultrahigh-pressure(UHP) terranes remains a puzzle in understanding lithospheric dynamic *** evidence that constrains the exhumation process of the Dabie UHP terrane includes the following.(1) Structural data record the architecture of the Dabie UHP *** slices are recognized—i.e.,from top to bottom,the Susong blueschist slice,the Huangzhen-Huangweihe(HH) HP slice,and the Jinheqiao-Shuanghe-Bixiling(JSB) UHP slice. These slices have been stacked and domed.(2) Geophysical data depict two offsets in the Moho. Offset-Ⅰseparates the Dabie UHP terrane from the North china craton,and has served as a subduction channel,as well as an exhumation ***-Ⅱ,separating the Dabie UHP terrane from the foreland belt,developed due to geodynamic regime reorganization.(3) Geochronological data reveal that the HP slice was exhumed earlier that the UHP slice.A northward-younging exhumation polarity is implied,with younger exhumation age closer to the exhumation channel. These pieces of evidence point to a multistage exhumation *** yangtze craton collided with and subducted beneath the North china craton at the very beginning of Triassic *** 230 Ma,the Susong blueschist slice and the southern end of the HH HP slice had arrived at a middle-crustal level,while its northern part was still at mantle *** processes continued until the JSB UHP slice was exhumed to mid-crustal levels at 210 *** geodynamic regime reorganization during 210-180 Ma,continuing compression of the yangtze craton and underthrusting along offset-Ⅱin the Moho caused the dome structure,and eventually brought the UHP rocks to the Earth’s surface.

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计算机工程与应用 2004年第22期40卷 182-184页

作者：吴志勤王赟宁书年李刚李国发中国矿业大学北京校区北京100083 中科院地质与地球物理研究所北京100029

论文针对地震数据量大且为结构化规则网格型体数据场的特点,根据地震解释的需要,对直接体绘制算法进行了简化和改进,利用OpenGL和Qt实现了Linux系统中地震数据的三维可视化,取得了较好的效果。

关键词：地震数据三维可视化直接体绘制 OpenGL Qt

Formation,evolution,reconstruction of black shales and their influence on shale oil and gas resource

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china geology 2024年第3期7卷 551-585页

作者： shi-zhen Li Qiu-chen Xu Mu Liu Guo-heng Liu yi-fan Li Wen-yang wang Xiao-guang yang Wei-bin Liu Yan-fei An Peng Sun Tao Liu Jiang-hui Ding Qian-chao Li Chao-gang Fang State Key Laboratory of Continental Shale Oil Beijing 100083China The Key Laboratory of Unconventional Oil and Gas geology China Geological SurveyBeijing 100083China Oil and Gas Survey China Geological SurveyMinistry of Natural ResourcesBeijing 100083China State Key Laboratory of Lithospheric and Environmental Coevolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Geosciences China University of Petroleum(East China)Qingdao 266580China School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Petroleum Resources Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Resource and Environment engineering Anhui UniversityHefei 230601China yangtze university Wuhan 430100China Nanjing Center China Geological SurveyNanjing 210016China National Elite institute of engineering CNPCBeijing 100096China

Black shales are important products of material cycling and energy exchange among the lithosphere,atmosphere,hydrosphere,and *** are widely distributed throughout geological history and provide essential energy and mineral resources for the development of human *** also record the evolution process of the earth and improve the understanding of the *** review focuses on the diagenesis and formation mechanisms of black shales sedimentation,composition,evolution,and reconstruction,which have had a significant impact on the formation and enrichment of shale oil and *** terms of sedimentary environment,black shales can be classified into three types:Marine,terrestrial,and marine-terrestrial transitional *** formation processes include mechanisms such as eolian input,hypopycnal flow,gravity-driven and offshore bottom *** a geological perspective,the formation of black shales is often closely related to global or regional major geological *** enrichment of organic matter is generally the result of the interaction and coupling of several factors such as primary productivity,water redox condition,and sedimentation *** terms of evolution,black shales have undergone diagenetic evolution of inorganic minerals,thermal evolution of organic matter and hydrocarbon generation,interactions between organic matter and inorganic minerals,and pore *** terms of reconstruction,the effects of fold deformation,uplift and erosion,and fracturing have changed the stress state of black shale reservoirs,thereby having a significant impact on the pore *** activity promotes the formation of veins,and have changed the material composition,stress structure,and reservoir properties of black *** resource effects,the deposition of black shales is fundamental for shale oil and gas resources,the evolution of black shales promotes the shale oil and gas formation and storage,and the reconstruction of black shales wou

关键词： Black shales Shale oil and gas Resource effects Sedimentary environment Sedimentary process Organic matter accumulation Diagenetic evolution Thermal evolution Organic matter and inorganic minerals Tectonic reconstruction Oil and gas exploration engineering Veins Fluid activity