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51.
北京昌平十三陵钻孔地应力测量与实时监测在断层活动危险性分析中的应用探讨 总被引:1,自引:0,他引:1
本文尝试运用北京昌平十三陵钻孔98 m深度原地应力测量和实时监测数据,依据弹性力学应力张量叠加原理,计算得到不同时段地应力结果;根据断层滑动摩擦准则,探讨南口山前断裂活动性,对了解该区地震危险性有重要的意义。原地应力测量与实时监测计算结果表明:在2010年1月初和2013年3月31日,最大水平主应力平均值分别为5.30 MPa和7.56 MPa,呈增加趋势;最大水平主应力方向也由NNW逐渐过渡到NE至近EW向。断层面上剪应力与正应力的比值结果显示:在2010年1月初和2013年3月底,平均比值分别为0.12和0.22,虽均没有达到断层面临界滑动摩擦系数0.6,但其显示出的增加趋势在一定程度上反映了该地区构造活动有增强的迹象,该现象值得关注。 相似文献
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黔中—渝南沉积型铝土矿的区域成矿模式概括如下:志留纪末的广西运动和泥盆纪末的紫云运动等,可能都是在峨眉地幔柱演化的壳幔相互作用阶段,因地幔柱向地壳大量输送物质和辐射能量,从而引发的地壳升降运动,在此期间,全区大面积抬升,形成长期隆起区;泥盆纪末准平原化;早石炭世岩关期气候湿热,暴露地表的早古生代岩石全面红土化、钙红土化,形成的含三水铝石红土风化壳物质,为沉积型铝土矿提供了物源。修文及息烽—遵义沉积区,于早石炭世大塘期早—中期沉积了铝土矿含矿岩系—九架炉组。绥阳—正安—道真沉积区,在晚石炭世的黄龙组石灰岩沉积并钙红土化之后,于马平期沉积了铝土矿含矿岩系的大竹园组。3个沉积区的铝土矿含矿岩系,都是在以陆相为主的环境中沉积形成的。在成岩阶段,铝土矿中的三水铝石逐渐变质为硬水铝石。由于各沉积区形成含三水铝石红土风化壳的母岩不同,由此沉积而成的铝土矿及其含矿岩系,在化学成分和矿物成分上也就有所差异。 相似文献
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为了描述岩石强度的各向异性特征,通过引入材料的微结构张量,考虑单轴抗压强度σcβ随层理倾角β而变化,提出了基于微结构张量的修正Hoek-Brown屈服准则。开展不同层理倾角(0°、15°、30°、45°、60°、75°和90°)的页岩试样不同围压(0、5、10、15和20 MPa)下的三轴压缩试验,结果显示,页岩峰值强度与层理倾角β呈"U"形曲线关系,在围压较低时呈"肩"形曲线关系,弹性模量Et和泊松比ν对围压不敏感,其平均值随层理倾角β的变化关系分别呈倒"U"形、"肩"形。页岩的微观和宏观破坏图像表明,其破坏模式受围压和层理倾角双重控制。试验值与模型预测值的对比表明,修正的Hoek-Brown屈服准则可较好地对页岩强度的各向异性进行模拟。同时,采用Koteshwar千枚岩、Koteshwar板岩、绿泥石片岩等层状结构岩石的单轴和三轴压缩试验数据,进一步验证了提出的修正Hoek-Brown屈服准则对多数具有层理结构的横观各向同性岩石峰值强度模拟具有普遍适用性,并对屈服准则在试验数据较多和较少情况下的峰值强度模拟效果进行了评价。 相似文献
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S. Heynisch A. Pekdeger B. Richter M. -Th. Schafmeister W. Skala 《Mathematical Geology》1994,26(4):505-517
Computer-based risk evaluation methods are practical tools to compare automatically and evaluate contaminated sites. HYDRISK is an example of adequate knowledge-based systems: HYDRISK evaluates hydrogeological properties and chemical criteria relevant to contaminant transport with respect to the necessary remedial actions. It works at a high investigative level and enables geologists and engineers to draw differentiated conclusions for selecting remediation methods for the contaminated site. HYDRISK emphasizes space and time dependent aspects of the contaminant transport. It is supported by a geographic information system (GIS) to display the evaluation results. Some ideas on considering the spatiotemporal variability of relevant parameters by means of geostatistical methods and numerical models will be given. 相似文献
59.
《The Professional geographer》1982,34(4):458-490
Books reviewed in this article: Aerial Photography and Remote Sensing. Terrain Analysis and Remote Sensing . JOHN R. G. TOWNSHEND , ed. Environmental Data Use in Computer-assisted Data Handling Systems: The Results of a Survey of Applications in the Pacific Northwest States . KENNETH E. GORDON . Applied Land Use: A Spatial Approach . JOHN F. LOUNSBURY , LAWRENCE M. SOMMERS , AND EDWARD A. FERNALD , eds. The Second Battle of New Orleans: A History of the Vieux Carre Riverfront-Expressway Controversy . RICHARD O. BAUMBACH , JR. AND WILLIAM E. BORAH . Cultural Environmental Archaeology . MYRA SHACKLEY . The Immoral landscape: Female Prostitution in Western Societies . RICHARD SYMANSKI . life Among the Poor in Cairo . UNNI WIKAN , translated by Ann Henning. Women, Work and Property in Northwest India . URSULA SHARMA . The Domestication of Women: Discrimination in Developing Societies . BARBARA ROGERS Economic Optimization in Locational and Transport Analysis . A. G. WILSON , J. D. COELHO , S. M. MACGILL , H. C. W. L. WILLIAMS . New Tools for Economic Development: The Enterprise Zone, Development Bank, and RFC . GEORGE STERNLIEB AND DAVID LISTOKIN , eds. Regional Wage Inflation . R. L. MARTIN , ed. Finding A Place For Energy-Siting Coal Conversion Facilities . FRANK J. CALZONETTI WITH MARK S. ECKERT . Environmental Management, Resources, and Systems Environmentalism. Second Edition . T. O'RIORDAN . Countryside Conservation . BRYN GREEN . Medical Spatial Diffusion: An Historical Geography of Epidemics in an Island Community . A. D. CLIFF , P. HAGGETT , J. K. ORD , AND G. R. VERSEY . Philosophy and Geographic Thought Order and Skepticism: Human Geography and the Dialectic of Science . RICHARD SZYMANSKI AND JOHN A. AGNEW . Measurement of Subjective Phenomena . D. F. JOHNSTON , ed. Conceptions of Space in Social Thought: A Geographic Perspective . ROBERT DAVID SACK . The Association of American Geographers: The First Seventy-five Years: 1904-1979 . PRESTON E. JAMES AND GEOFFREY J. MARTIN . The Life and Thought of Isaiah Bowman . GEOFFREY J. MARTIN . Physical River Basin Planning: Theory and Practice . SURANJIT K. SAHA AND CHRISTOPHER J. BARROW , eds. Soils and landforms: An Integration of Ceomorphology and Pedology . A. I. GERRARD Climatic Change and Society. Consequences of Increasing Atmospheric Carbon Dioxide . WILLIAM W. KELLOGG AND ROBERT SCHWARE . Political Political Redistrictings and Geographic Theory . RICHARD L. MORRILL . Population Studies in Spanish American Population History: Dell Plain Latin American Studies NO. 8 . DAVID J. ROBINSON , ed. Population Redistribution in the Midwest . CURTIS C. ROSEMAN , ANDREW J. SOFRANKO , AND JAMES D. WILLIAMS , eds. Geographical Perspectives on the Elderly . A. M. WARNES , ed. Regional Perspective On the American South . MERLE BLACK AND JOHN SHELTON REED , eds. The Prairies and Plains: Prospects for the 80s . JOHN R. ROGGE , ed. Rural Rural Settlement in an Urban World . MICHAEL BUNCE . Social Accident at Three Mile Island: The Human Dimensions . DAVID L. SILLS , C. P. WOLF , AND VIVIEN B. SHELANSKI , eds. The American Small Town: Twentieth-Century Place Images . JOHN JAKLE . Urban A House of My Own . SUSAN LOBO . The City: Patterns and Processes in the Urban Ecosystem . CHRISTOPHER H. EXLINE , GARY L. PETERS , AND ROBERT P. LARKIN . Movement in Cities . P. W. DANIELS AND A. M. WARNES . Urbanization and Urban Planning in Capitalist Society . MICHAEL DEAR AND ALLEN J. SCOT , eds. 相似文献
60.
Methodological Development of the Conditional Sampling Method. Part II: Quality Control Criteria of Relaxed Eddy Accumulation Flux Measurements 总被引:1,自引:1,他引:0
A.?K.?Fotiadi F.?Lohou A.?Druilhet D.?Ser?aEmail author F.?Said P.?Laville A.?Brut 《Boundary-Layer Meteorology》2005,117(3):577-603
Determination of biosphere–atmosphere exchanges requires accurate quantification of the turbulent fluxes of energy and of
a wide variety of trace gases. Relaxed Eddy Accumulation (REA) is a method that has received increasing attention in recent
years, because it does not require any rapid sensor for the scalar measurements as the Eddy Correlation method (EC) does.
As in all micrometeorological studies, REA measurements in the atmospheric surface layer are valid under some restrictive
conditions so as to be representative of a specific ecosystem. These conditions are the homogeneity of the underlying surface,
stationary and horizontally homogeneous turbulence. For most experiments these conditions are not fully satisfied. Data uncertainties
can also be related to not fulfilling the method principles or to the technical characteristics of the REA system itself.
In order to assess REA measurement quality, a methodological approach of data analysis is developed in this study. This methodological
analysis is based on the establishment of criteria for data quality control. A set of them, deduced from the mean and turbulent
flow, are called ‘Dynamic criteria’ and are designated to control the stationarity and homogeneity of the w function and the validation of Taylor’s hypothesis. A second set (‘REA operational criteria’) is designed to check the sampling
process and, more precisely, the homogeneity of the negative and positive selection process throughout the sampling period.
A third set of criteria (‘Chemical scalar criteria’) concerns the scalar measurements. Results of the criteria application
to data measured at two different experimental sites are also presented. Cut-off limits of criteria are defined based on their
statistical distribution and shown to be specific for each site. Strictness of each criterion, defined by the percentage of
flagged samples, is analysed in conjunction with the meteorological conditions and atmospheric stability. It is found that
flagged samples mainly correspond to neutral and stable nocturnal conditions. During daytime, nearly free convection conditions
can also yield poor quality data. 相似文献