共查询到20条相似文献，搜索用时 140 毫秒
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高密度电阻率法地形影响校正 总被引：1，自引：0，他引：1
采用有限元法实现高密度电阻率法二维模型的正演模拟,将一定地形条件下的二维地电模型的视电阻率响应,分解为畸变场和正常场二部分进行分析.采用比值法消除由地形引起的畸变场,从而获得水平地形条件下二维地电结构的视电阻率值.在实际资料的校正中,取得了较好的应用效果. 相似文献
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大地电磁测深资料常规反演方法的应用现状及进展 总被引：1，自引：0，他引：1
文中介绍了大地电磁测深(MT)资料处理解释中几种常规地球物理反演方法的基本原理及该领域内的最新进展,通过应用实例分析说明在进行资料定量解释的过程中应该多种反演手段相互佐证.可以用BOSTICK反演结果建立初始模型,通过一维、二维反演,在结合地质、物探资料并通过正演模拟计算验证的基础上,建立合理的地质-地球物理模型.利用综合信息建模及反演成像技术结合现代地质理论,能有效地降低解的非唯一性,提高解释结果的可靠程度及综合地质解释结果的合理性. 相似文献
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《物探化探计算技术》2019,(6)
从电磁探测软件的需求、设计和技术实现等方面,介绍软件的开发过程和功能。在软件设计与开发中应用软件工程技术流程,分别对时间域激电法(TDIP)、大地电磁法(MT)、可控源音频大地电磁法(CSAMT)和频谱激电法(SIP)四种电磁方法正反演模块的软件集成进行需求分析和系统设计,形成一套完整的开发文档。针对SIP二维正反演计算、CSAMT二维正演计算和MT三维正反演模块应用并行计算技术,达到提高软件计算效率的目的,同时在软件中集成可视化技术与人机交互建模技术,提升软件的实用性。 相似文献
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利用对非水平层状介质的地质结构首先进行二维模型的正演模拟,尔后对模拟曲线再进行一维反演来确定层状结构特征,实现由一维反演初步解释二维电阻率构造的解释过程。通过对三个不同结构特征的二维模型的解释结果表明,采用这种方法能够解释简单的二维电阻率构造,尤其是对于确定存在横向电阻率差异的界面效果更好;而且利用一个简单的经验公式在等值线断面图上通过求解截止电阻率值达到确定异常体的几何形态 相似文献
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一、功能本程序用于以人机结合选择法解二度重力勘探的反演问题。程序包括正演计算、绘图打印、物质带等效源反演计算三部分。正演计算采用水平多边形棱柱公式,可以有多个地质体,各地质体可以有不同的剩余密度。地形可以是平坦的或起伏的。在每次正演计算前,绘出本次计算所依据的地形地质剖面图。正演计算后,绘出异常剖面图。然后,由用户酌情选 相似文献
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The Main Tuff Interval (MTI) is a 3.5 to 16.4 m thick sequence of pyroclastic turbidites in the Wittenoom Formation of the late Archean to early Proterozoic Hamersley Group, Western Australia. The Hamersley Group accumulated in a basin located on the Archean Pilbara Craton, Western Australia. MTI pyroclasts formed via hydrovolcanic eruption processes from a magma that was likely intermediate in composition. Eruption took place in a shallow subaqueous setting. The MTI was deposited by high- and low- concentration turbidity currents in four overlapping regional depositional packages. Paleocurrent and stratigraphic data indicate the MTI source lay to the north of the present exposure limits of the Hamersley Group on the Pilbara Craton, and was likely to have been a single volcano. Reflection of turbidity currents in the southeastern part of the study area and westward travel of the reflected flows indicate that the Hamersley Group depositional basin shallowed to the east and south at the time of MTI deposition. The presence of the MTI source volcano on the northern Pilbara Craton indicates that the subsidence and marine deposition recorded by the Hamersley Group may be limited to the southern portion of the craton, and that volcanism may have continued on the northern Pilbara Craton. 相似文献
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A Relative Moment Tensor Inversion Technique Applied to Seismicity Induced by Mining 总被引：1，自引：0，他引：1
L. M. Linzer 《Rock Mechanics and Rock Engineering》2005,38(2):81-104
Summary. Studies of source mechanisms of mining-induced seismic events play an important role in understanding the various modes of failure observed around underground excavations and enable the geometry of likely planes of failure to be determined. These planes can be mapped using conventional techniques, for example, geological fracture mapping. However, such an approach is often problematical due to limited access to the site and/or poor exposures (if any) of the failure plane. An added difficulty is that planes of failure often do not follow faults of geological origin, but are related to the geometry of the advancing stope face. For example, the development of face-parallel shear zones ahead of deep-level stope faces. In such cases, the stresses induced by mining dominate over the geological structure in the critical region close to the stope face. Seismic methods therefore have the potential of being a practical method of studying the development of seismic shear zones underground.Slip on such a failure plane generates a three dimensional elastic wave that propagates through the rockmass, carrying a wealth of information regarding the source rupture process. The ground motions caused by the passage of the wave can be recorded by arrays of sensitive instruments called seismometers. These sets of recordings (seismograms) provide the basic data that seismologists use to study these elastic waves as they propagate through the Earth. Conventional seismic analyses provide scalar measurements of the rupture size and intensity. However, through a process known as moment tensor inversion (MTI), the seismograms recorded from a seismic event can be used to calculate a moment tensor that describes the three dimensional nature of the source mechanism. Interpretation of the moment tensor gives insight into whether the rockmass failed in tension, compression or shear and indicates the direction of movement and the failure plane.Moment tensor solutions computed using conventional MTI methods are sensitive to noise and may be biased due to systematic errors in the measurements. The primary objective of this study was to develop a robust MTI method to estimate the moment tensors of clusters of seismic events recorded in the underground environment. To achieve this, three hybrid MTI methods were developed by the author. These methods involve different iterative weighting schemes designed to enhance the accuracy of the computed moment tensors by decreasing the effect of outliers (data points whose residuals lie far from the mean or median error). The additional information required for hybrid methods is obtained by considering a spatial cluster of seismic events and assuming that the waves generated by each event in the cluster follow a similar path through the rockmass and allowing a common ray-path to be assumed. Hence the unknown effect of the heterogeneous rockmass on the waveform is similar for all the events in the cluster.The final objective was to determine whether the techniques developed could be successfully applied to real data. The hybrid MTI methods using the median and the weighted mean correction were applied to a cluster of 10 events, having remarkably similar waveforms, recorded at Oryx Gold Mine. For comparative purposes, the more conventional absolute method was also applied. The solutions computed using the hybrid MTI with a median correction displayed a distinct improvement after the iterative residual correction procedure was applied, in contrast to the solutions obtained from the absolute method. The radiation patterns and fault-plane solutions from the hybrid method showed a high degree of similarity, and were probably more accurate reflections of reality. These observations are very encouraging and point towards the potential for using the hybrid MTI method with a median correction as a standard processing tool for mine seismicity.The implications of this work are that a robust method for calculating the focal mechanisms of clusters of seismic events induced by mining activities has been developed. Regular application will lead to a better understanding of rock fracture processes and to improved safety underground. 相似文献
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Tingting Yao 《Mathematical Geology》2002,34(4):387-403
Clastic reservoir characterization starts typically with modeling lithofacies distribution and geometry. The architecture of the reservoir, governed by the lithofacies geometry, is a major source of heterogeneity in such clastic systems. Seismic data provide potentially valuable information about the areal distribution of different lithofacies, such as the averaged prior proportion of each lithofacies. However, seismic data are available only at coarse vertical resolution rather than the fine lithofacies sampling along wells, hence seismic is considered equivalent to 2D data while building 3D geological models. This scale difference between the seismic data and the lithofacies data available along the wells makes direct integration difficult. Different algorithms have been proposed to integrate the seismic data: (1) duplicate seismic data along the vertical line and use the prior proportions provided by the seismic data as prior local means; (2) integrate the 2D seismic data as collocated block averages; and (3) duplicate seismic data along the vertical line and integrate them using a Markov-Bayes algorithm. These three algorithms are applied on a data set originating from a real clastic reservoir. The results are compared with regard to how much kriging weight is applied to the seismic data and how well the information from seismic data is honored. 相似文献
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三维地理信息系统（3D—GIS）的发展现状及趋势 总被引：15，自引：0，他引：15
地理信息系统技术已经被大量应用于资源管理,环境监测,城市规划,土地管理及交通,水利,林业等领域,但ＧＩＳ技术的发展还远没有止境。人们已经不满足于传统的二维ＧＩＳ软件平台,取而代之的是空间的,立体的三维ＧＩＳ。但由于３Ｄ－ＧＩＳ包括了第三个坐标以及从平面到立体的换算,所以增加了大量的存储量和额外的数据量,因而时至今日,真正的３Ｄ－ＧＩＳ软件还很少。本文一方面介绍了３Ｄ－ＧＩＳ的概念,特点以及发展现状 相似文献
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《Geodinamica Acta》2013,26(3-4):155-164
New structural data pointed out the presence of an older scattered migmatization event (Devonian?, M1) overcome by the well known Variscan migmatization event (Lower-Middle Carboniferous, M2) related to the Late extensional tectonic that affected the High Grade Metamorphic Complex (HGMC) in the Variscan Belt of Sardinia (Italy). The M1 event is only recognizable in the kyanite – amphibole bearing migmatitic gneiss. Both migmatization events (M1 and M2) are characterized by a syn-tectonic non coaxial deformations (D1 and D2 deformational events). D1 shows a top to NW sense of shear while the D2 event a top to NE/SE sense of shear (the shear senses are considered at the present Sardinia – Corsica block position in the Mediterranean sea). The M2+D2 is characterized by a complicate, composite normal shear network; the M1+D1 by inverse shear zones. The M2+D2 is transposed by the late D3 strike slip shear event: the D3 is characterized by strike slip shear zones syn-kinematic to the emplacement of Late Carboniferous granitoids (320 Ma – 300 Ma). Despite the absence of geochronological data about the M1+D1 event, the field relationships suggest, for first time, an older migmatization process (Devonian?) syn-tectonic with the late stage of thickness of the Sardinia Variscan Belt. Similar evolutions are recognized in different segments of the Variscan Belt such as the Massif Central (France) or in the eastern mid-European Variscides. 相似文献
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随着空间信息技术、地学信息技术和GIS等技术的飞速发展,利用QT结合OpenGEL技术建立基于3D WebGIS月球地质空间数据管理系统。该系统包含二维成果管理系统、发布系统与三维月球研究3个子系统,实现改善月球资料信息使用效率、信息化程度与多源空间数据共享。将中国探月计划所获取的月球地形地貌、岩层、土壤、资源、环境及各种相关数据资料与研究成果,以及国外包含数据、文献、报告等月球探测的研究最新成果集成在一起,建立了中国第一个月球地质空间数据管理系统。该信息系统既包含管理和服务功能,又提供面向科研、决策的信息服务与科学的分类管理、快速检索和联机查询的功能。地质空间数据管理系统具备强大的数据综合分析能力、综合管理月球地质资料与集成数据资料成果的汇总能力,将为中国探月工程提供有力的支撑。 相似文献
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RobertD.JACOBI 《《地质学报》英文版》2003,77(4):491-503
2-D and 3-D densities of fractures are commonly used in mining safety design, natural gas and oil production in fractured reservoirs, and the characterization of subsurface flow and transportation systems in fractured rocks. However, many field data sets are collected in 1-D frequency (f) (e.g., scanlines and borehole data). We have developed an ARC/ INFO-based technology to calculate fracture frequency and densities for a given fracture network. A series of numerical simulations are performed in order to determine the optimal orientation of a scanline, along which the maximum fracture frequency of a fracture network can be obtained. We calculated the frequency (f) and densities (both D1 and D2) of 36 natural fracture trace maps, and investigated the statistical relationship between fracture frequency and fracture density D1, i.e. D1=1.340f+ 0.034. We derived analytical solutions for converting dimensional density (D1) to non-dimensional densities (D2 and D3) assuming that fracture length distribution f 相似文献
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Jun-Qi Liu Xiao-Ping Mao Chong-Long Wu Zhang-Qian 《Journal of the Geological Society of India》2013,82(5):570-574
True 3D solid modeling of complex geologic bodies still face many difficulties. In this paper, a new technique of true 3D solid modeling is addressed, which incorporates the application of 2D&3D interactive aided section technology to revise scatter point aggregates, the means of two-body 3D data structure (improved B-rep 3D solid data structure) to organize data and the usage of vector shear technology for modeling. Based on such techniques, a true 3D solid model of a large hydropower engineering project in southern China was built to serve as intuitive platform for engineering survey, design, and construction. In the light of its wide application to many projects, it can be considered as a reasonable and effective method for 3D modeling of complex geologic bodies. 相似文献
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ZHANG Letian YE Gaofeng JIN Sheng WEI Wenbo Martyn UNSWORTH Alan G. JONES JING Jianen DONG Hao XIE Chengliang Florian LE PAPE Jan VOZAR 《《地质学报》英文版》2015,89(1):90-104
Project INDEPTH (InterNational DEep Profiling of Tibet and the Himalaya) is an interdisciplinary program designed to develop a better understanding of deep structures and mechanics of the Tibetan Plateau. As a component of magnetotelluric (MT) work in the 4th phase of the project, MT data were collected along a profile that crosses the eastern segment of the Altyn Tagh fault on the northern margin of the plateau. Time series data processing used robust algorithms to give high quality responses. Dimensionality analysis showed that 2D approach is only valid for the northern section of the profile. Consequently, 2D inversions were only conducted for the northern section, and 3D inversions were conducted on MT data from the whole profile. From the 2D inversion model, the eastern segment of the Altyn Tagh fault only appears as a crustal structure, which suggests accommodation of strike slip motion along the Altyn Tagh fault by thrusting within the Qilian block. A large-scale off-profile conductor within the mid-lower crust of the Qilian block was revealed from the 3D inversion model, which is probably correlated with the North Qaidam thrust belt. Furthermore, the unconnected conductors from the 3D inversion model indicate that deformations in the study area are generally localized. 相似文献