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81.
The Khanaser Valley was geoelectrically thoroughly surveyed through a grid which consisted of twelve VES profiles. The tectonically-oriented Pichgin and Habibullaev method was enhanced to be applicable in areas of rugged relief and topography. The enhanced profiles were tectonically interpreted and subsurface structures within the Khanaser Valley were delineated. Accordingly, a tectonic evolutional scenario of the valley was established and its hydrogeological characteristics were derived. An approach for groundwater exploration in areas of prominent relief and topography in dry areas such as the Khanaser Valley was established and its validity was estimated.  相似文献   
82.
A system is proposed for the monitoring of changes in the underground structure of an active volcano over time by applying a transient electromagnetic method. The monitoring system is named ACTIVE, which stands for Array of Controlled Transient-electromagnetics for Imaging Volcano Edifice. The system consists of a transmitter dipole used to generate a controlled transient electromagnetic (EM) field and an array of receivers used to measure the vertical component of the transient magnetic field at various distances, with automatic operation of both units. In order to verify the performance of the proposed system, numerical and field experiments were carried out by application of the system to the Izu-Oshima volcano, where a remarkable change in the apparent DC resistivity over time had been detected in association with the eruption in 1986.  相似文献   
83.
研究了运用高密度电法观测系统作常规电法联合剖面的野外工作方法及数据整理过程,运用高密度电法观测系统,将高密度电法测量与常规联合剖面测量同时进行,有利于对异常体作分析解释。  相似文献   
84.
将物探电法的测点数据及测点的大地直角坐标按每条测线上测点由西向东的顺序 ,以统一编号、线号、点号、横坐标、纵坐标、测点数据为字段建成MicrosoftAccess数据库。根据制图比例尺和测点的大地直角坐标逐个计算数据库中所有测点在图纸上的坐标值 ,绘制测点位置子图 ,并在测点位置沿垂直测线方向向东移动 1/ 2测点数据注释的字符宽度 ,并以测点位置为圆心顺时针旋转 6 0°的位置绘制测点数据注释。按照上述方法 ,以MicrosoftVC + + 6 0为工具 ,利用MAPGIS 6 1地理信息系统二次开发技术 ,编制数据处理程序 ,实现电法原始数据图的微机制图  相似文献   
85.
86.
Conductivity models were compiled in two geological provinces with thinsediments. The first province is the margin of the Precambrian East EuropeanPlatform. The second one is the Phanerozoic Rhenish Massif as a part of CentralGermany Hercinicum. In both provinces, a conducting layer was revealed at thebase of the upper crust by the magnetotelluric soundings. Its depth is around10 km in the East European Platform and around 15 km in the Rhenish Massif.The conductance of the layer reaches a few tens of Siemens in the first provinceand is almost an order of magnitude greater in the second one.A good correlation between the conductor and a seismic wave-guide (low-velocityzone) exists at the base of the upper crust. Simultaneous decrease of both electricalresistivity and seismic velocity, suggests an increase of porosity and permeability inpresence of saline water. The depth of rheological weak layer in the PhanerozoicRhenish Massif corresponds to the commonly accepted depth of the thermallyinduced brittle/ductile transition. Contrary similar layer in the Precambrian EasternEuropean Platform is much shallower than the thermally induced transition. Somenew mechanism should be considered.  相似文献   
87.
利用室内电提取法寻找隐伏矿床的试验   总被引:5,自引:1,他引:5  
利用室内电提取法寻找隐伏矿试验取得了很好的效果,能发现埋深较大的隐伏矿体,其具有研究和推广应用的前景。  相似文献   
88.
An electrical substation consists of a complex set of equipment items that are interconnected through conductor buses or cables. If the connections are not sufficiently flexible, significant dynamic interaction may occur between the connected equipment items during a seismic excitation. This interaction is believed to be responsible for some of the observed substation equipment damage in recent earthquakes. This paper investigates the interaction between two equipment items connected by a linear spring‐dashpot or spring‐dashpot‐mass element representing a conductor bus. It is found that the interaction between the two equipment items may significantly amplify the response of the higher‐frequency equipment item. The influences of various key parameters on the interaction effect are quantified. Means for reducing the adverse interaction effect are described. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
89.
This paper deals with the electrical double layer and the related properties of porous media. In particular, the electrical conductivity, the streaming potential, and the membrane potential are described in a self-consistent set of equations. All these properties are shown to be governed by fluid-matrix interface properties, as well as four geometrical parameters.  相似文献   
90.
地震监测设施点多面广,被盗、被破坏的情况时有发生,直接和间接的经济损失十分严重。由此引起的仪器停记,造成资料中断的损失则无法用金钱计算、针对此问题,我们运用模糊控制技术技术,研制开发了FD-1型多功能防盗报警器。它通过检测来访者的文明程度,采取一系列相应的反击措施:即自动打开室内灯光、电视机、录音机等,造成室内有人的假象;对不知趣者给予警告、警铃……直至发出"有电危险,请勿靠近"的警告和电击(无生命危险),达到御敌于门外之目的。该报警器不仅适用于地震台站,也广泛用于各企业事业单位和家庭防盗等。  相似文献   
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