微动探测：地层分层和隐伏断裂构造探测的新方法   总被引：3，自引：0，他引：3  

徐佩芬  李世豪  杜建国  凌苏群  郭慧丽  田宝卿 《岩石学报》2013,29(5):1841-1845

微动探测作为地层分层和隐伏断裂构造探测的物探新方法,已成为盆地结构调查、地热井位选址和隐伏地质构造探测的重要物探手段.微动测深确定岩性差异较大的地质界面,如新生界地层底界、侏罗系与二叠系地层分界面、二叠系-石炭系灰岩顶界面等,深度误差可控制在5％左右.断层破碎带/隐伏断裂构造在微动视S波速度剖面上显示为低速异常或明显的速度差异,易于识别、解释.二维微动剖面技术已在探测隐伏地质构造(断层、陷落柱等)方面取得较好地质效果.本文介绍其原理、方法和应用实例.  相似文献   

GIS,multi‐criteria and multi‐factor spatial analysis for the probability assessment of the existence of illegal landfills     

Giancarlo Biotto  Lucia Gobbo  Elisa Furlan  Sonia Valenti  Roberto Rosselli 《International journal of geographical information science》2013,27(10):1233-1244

This work deals with the identification of potentially contaminated areas using remote sensing, geographic information systems (GIS) and multi‐criteria spatial analysis. The identification of unknown illegal landfills is a crucial environmental problem in all developed and developing countries, where a large number of illegal waste deposits exist as a result of fast, and relatively unregulated, industrial growth over the past century. The criteria used to perform the spatial analysis are here selected by considering the characteristics which are ‘desirable’ for an illegal waste disposal site, chiefly related to the existence of roads for easy access and to a low population density which facilitates unnoticed dumping of illegal waste materials. A large dataset describing known legal and illegal landfills and the context of their location (population, road network, etc.) was used to perform a spatial statistical analysis to select factors and criteria allowing for the identification of the known waste deposits. The final result is a map describing the likelihood of an illegal waste deposit to be located at any arbitrary location. Such a probability map is then used together with remote sensing techniques to narrow down the set of possibly contaminated sites (Silvestri and Omri, 2008 Silvestri, S. and Omri, M. 2008. A method for the remote sensing identification of uncontrolled landfills: formulation and validation.. International Journal of Remote Sensing, 29(4): 975–989. [Taylor & Francis Online] , [Google Scholar]), which are candidates for further analyses and field investigations. The importance of the integration of GIS and remote sensing is highlighted and represents a key instrument for environmental management and for the spatially‐distributed characterization of possible uncontrolled landfill sites.  相似文献   

冀中坳陷霸县凹陷文安斜坡潜山油气成藏模式与勘探发现   总被引：1，自引：0，他引：1  

王建瑞  刘趁花  郭永军  朱洁琼  金涛 《海相油气地质》2012,17(1):35-40

利用已钻井资料及高精度叠前时间偏移三维地震资料,对冀中坳陷文安斜坡基岩结构特征、潜山内幕反射结构和已钻井分析表明,斜坡南段潜山内幕寒武系发育有多套储盖组合,油源来自霸县洼槽下第三系沙河街组和孔店组,大断层面、不整合面和渗透层构成油气运移通道。构建了"坡腹层状古储古堵古盖油气藏"潜山内幕成藏新模式,并发现落实了一批潜山内幕圈闭,优选钻探文古3井,于下寒武统府君山组获得高产工业油气流。回顾了构建潜山成藏新模式和文古3潜山油藏的勘探发现历程,并描述了该油藏的基本特征。  相似文献   

冀北丰宁县茶棚银矿床成矿模式     

李会恺  张翔君 《云南地质》2012,(3):413-416

茶棚银矿属与隐伏岩体/次火山岩有关的浅成低温热液矿床。侏罗系盖层继承下伏基底变质岩系中成矿元素的高背景;隐伏岩体/次火山岩提供热源和部分物源;近SN向断裂为元素富集提供成矿空间。研究成果可以指导同类浅剥蚀区隐伏矿体的找矿工作。  相似文献   

OSL and TL dating of buried podsols and overlying sands in Ostrobothnia,western Finland     

G. Hütt  H. Jungner  R. Kujansuu  M. Saarnisto 《第四纪科学杂志》1993,8(2):125-132

In Ostrobothnia, western Finland, buried fossil soils have been recognised in a number of places in the sandy sediments that occur between glaciofluvial deposits and overlying till. Samples from the soil horizons as well as below and above them were taken for optically stimulated luminescence (OSL) dating. The same sites were also sampled for thermoluminescence (TL) dating. Altogether five TL dates and seventeen OSL dates were obtained. The OSL dates can be grouped into two age classes, (i) 120-163 ka and (ii) 76-106 ka, whereas all TL dates are of the order 135-155 ka. A comparison between the results obtained from the two dating methods shows that OSL dates are generally younger than the TL dates for the same sample. The discrepancy may arise partly from problems of setting a correct residual level in TL dating. If this is the case then the TL dates may indicate an upper limit for the true age. The results support the geological interpretation that the fossil soils were formed during the last interglacial, that the soil-forming processes possibly also continued during the first Early Weichselian stadial and interstadial (Brørup sensu lato), and that in general the till-covered glaciofluvial sequences, interpreted as eskers in Ostrobothnia, were deposited during the Saalian or Early Weichselian deglaciation.  相似文献   

Stress analysis of buried steel pipelines at strike-slip fault crossings   总被引：3，自引：0，他引：3  

Dimitrios K. Karamitros  George D. Bouckovalas  George P. Kouretzis 《Soil Dynamics and Earthquake Engineering》2007,27(3):200-211

Existing analytical methods for the stress analysis of buried steel pipelines at crossings with active strike-slip faults depend on a number of simplifications, which limit their applicability and may even lead to non-conservative results. The analytical methodology presented herein maintains the well-established assumptions of existing methodologies, but also introduces a number of refinements in order to achieve a more wide range of application without any major simplicity sacrifice. More specifically, it employs equations of equilibrium and compatibility of displacements to derive the axial force applied on the pipeline and adopts a combination of beam-on-elastic-foundation and elastic-beam theory to calculate the developing bending moment. Although indirectly, material and large-displacement non-linearities are also taken into account, while the actual distribution of stresses on the pipeline cross-section is considered for the calculation of the maximum design strain. The proposed methodology is evaluated against the results of a series of benchmark 3D non-linear analyses with the finite element method. It is shown that fairly accurate predictions of pipeline strains may be obtained for a wide range of crossing angles and fault movement magnitudes encountered in practice.  相似文献   

Middle to Late Holocene glacial variations, periglacial processes and alluvial sedimentation on the higher Apennine massifs (Italy)   总被引：1，自引：0，他引：1  

Carlo Giraudi 《Quaternary Research》2005,64(2):176-184

The major climatic variations that have affected the summit slopes of the higher Apennine massifs in the last 6000 yr are shown in alternating layers of organic matter-rich soils and alluvial, glacial and periglacial sediments. The burial of the soils, triggered by environmental-climatic variations, took place in several phases. For the last 3000 yr chronological correlations can be drawn between phases of glacial advance, scree and alluvial sedimentation and development of periglacial features. During some periods, the slopes were covered by vegetation up to 2700 m and beyond, while in other phases the same slopes were subject to glacial advances and periglacial processes, and alluvial sediments were deposited on the high plateaus. Around 5740-5590, 1560-1370 and 1300-970 cal yr B.P., organic matter-rich soils formed on slopes currently subject to periglacial and glacial processes; the mean annual temperature must therefore have been higher than at present. Furthermore, on the basis of the variations in the elevation of the lower limit reached by gelifraction, it can be concluded that the oscillations in the minimum winter temperatures could have ranged between 3.0°C lower (ca. 790-150 cal yr B.P.) and 1.2°C higher (ca. 5740-5590 cal yr B.P.) than present minimum winter temperatures. During the last 3000 yr the cold phases recorded by the Calderone Glacier advance in the Apennines essentially match basically the phases of glacial advance in the Alps.  相似文献   

Vertical impulse measurements of mines buried in saturated sand     

LC Taylor  RR Skaggs  W. Gault 《Fragblast: International Journal for Blasting and Fragmentation》2005,9(1):19-28

The ultimate aim of our overall task, of which the effort described in this paper is a part, is to be able to model the impulsive output of buried charges and the response of targets of interest. It is not practical or cost-effective to determine the response of all targets of interest to buried charges of all sizes by testing them. In order to have confidence in our models, however, they must be validated by a modest number of tests. A critical element in modelling the response of a target is the ability to model the loading function. The load a buried charge applies to a target above it when the charge detonates can be characterized in terms of the vertical impulse. The vertical impulse is a function of the size of the charge, its depth of burial, and the properties of the soil in which it is buried. The primary objective of the effort described in this paper is to determine the load a known charge places on a non-responding target so the data can be used to validate our models.

For model validation, a large number of detonator-scale experiments have been conducted by the University of Maryland (Fourney et al. [1]). It was also necessary to conduct a modest number of experiments at a larger scale, nine in total, to ensure that the results of the detonator-scale tests can be satisfactorily scaled up. Of the nine large-scale experiments conducted, seven were conducted with 5 or 10 lb cast TNT charges. All experiments were conducted in sand that was as nearly fully water-saturated as possible. The objective of the experiments was to determine the vertical impulse applied to a non-deforming target plate above the charge.

The large-scale experiments were conducted using the Vertical Impulse Measurement Fixture (VIMF) at the Army Research Laboratory, Aberdeen, MD. The VIMF is a unique facility that has been designed specifically to measure accurately the vertical impulse from buried charges weighing up to 8 kg.

This paper describes the VIMF and its instrumentation, test methods and test results. The results obtained demonstrate that in some cases, when the soil is saturated sand, explosive 'bubble' effects similar to those encountered in shallow water are encountered.  相似文献   

瞬变电磁法、时间域激电法在勐兴铅锌矿的应用   总被引：2，自引：0，他引：2  

罗鉴凡  廖忠 《云南地质》2002,21(4):421-427

勐兴铅锌矿矿石品位低，埋深大，且面临资源匮竭。采用瞬变电磁法（TEM）和激电法（IP），合理布线展网，反复印证，得到多个物探组合异常。异常源位于下志留统下仁和桥组。经钻孔验证，获得相当于原保有储量3倍的新储量，找矿效果突出。  相似文献   

高寒地区浅基础埋深问题     

那云龙  车富强 《工程地质学报》2001,9(2):223-224

运用工程实例论述了影响高寒地区浅基础埋深的重要因素, 提出了基础埋深的具体计算方法。  相似文献