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91.
D. M. Morrison 《Pure and Applied Geophysics》1989,129(3-4):619-645
Microseismic systems at five mines in the Sudbury Basin provide the basic data for Falconbridge Limited's rockburst research. Daily and long-term analysis of this data as well as underground observations have confirmed the fault-slip mechanism at three mines. A detailed analysis of the complete history of Falconbridge Mine is being conducted and Distinct Element numerical models are being used to simulate both the stick-slip behaviour of faults and the dynamic effects of the induced vibrations on rock and backfill. University research includes acoustic tomographic imaging of the rock mass based on seismic wave propagation and collection of full microseismic waveforms to allow application of advanced seismic and statistical analysis techniques.Formerly with Mines Technical Services, Falconbridge Limited, Sudbury Operations, Falconbridge , Ont., P0M 1S0.Presented at the Fred Leighton Memorial Workshop on Mining Induced Seismicity, Montreal, Canada, August 30, 1987. 相似文献
92.
R. P. Young D. A. Hutchins S. Talebi T. Chow S. Falls L. Farrell D. Jansen J. McGaughey J. Towers T. Urbancic 《Pure and Applied Geophysics》1989,129(3-4):647-659
The progress made on three phases of a research project, started in 1986 to investigate mining induced seismicity/rockburst phenomena using concurrent geotomographic imaging and microseismic monitoring techniques, is described. Phase I is the geotomographic software development and laboratory calibration trials. Phase II is the enhancement of traditional microseismic monitoring instrumentation with a waveform acquisition system, so that source mechanism studies can be carried out on mining induced seismic events. Phase III is the field trials of the hybrid technique which will be used to monitor changing rock mass physical properties, in response to mining. Preliminary results from all three phases are given, together with an outline of current and future research planned.Presented at the Fred Leighton Memorial Workshop on Mining Induced Seismicity, Montreal 1987. 相似文献
93.
Transport properties of rocks from statistics and percolation 总被引:7,自引:0,他引:7
Two simplified microstructural models that account for permeability and conductivity of low-porosity rocks are compared. Both models result from statistics and percolation theory. The first model assumes that transport results from the connection of 1D objects or pipes; the second model assumes that transport results from the connection of 2D objects or cracks. In both cases, statistical methods permit calculation of permeability k and conductivity , which are dependent on three independent microvariables: average pipe (crack) length, average pipe radius (crack aperture), and average pipe (crack) spacing. The degree of connection is one aspect of percolation theory. Results show that use of the mathematical concept of percolation and use of the rock physics concept of tortuosity are equivalent. Percolation is used to discuss k and near the threshold where these parameters vanish. Relations between bulk parameters (permeability, conductivity, porosity) are calculated and discussed in terms of microvariables. 相似文献
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本文针对山区电测深的结症,通过实例介绍了一种新方法──多源电测深法的应用效果。在三面环山、岩石裸露等物探自然条件极为不利的情况下,应用多源电测深法成功地圈定了8411西段铀-硅质体的展布,预测了银竹凹铀成矿远景区段,为8411矿床的扩大指明了方向。实践表明:多源电测深法具有探测深度大、工作效率高、资料解释直观可靠等优点,是一种行之有效的物探方法。 相似文献
100.
本文叙述了大地电磁视电阻率和阻抗相位资料联合解释的原理与计算方法。通过具体算例的分析,表明该方法是正确有效的,而且在缩小多解性方面,要比单纯的视电阻率资料反演法或阻抗相位资料反演法优越 相似文献