共查询到19条相似文献,搜索用时 125 毫秒
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介绍了矿山地震与瓦斯突出等煤矿灾害及成因, 并通过若干煤矿瓦斯突出和矿山地震的同震现象,论述了这些灾害在动力过程中的内在关系.这些震例表明,在高瓦斯煤矿, 矿山地震与瓦斯突出存在密切的相关.认为较大矿震伴随瓦斯的低值延时响应可能是瓦斯突出的预警信号.从矿震定位、震源机制、矿震成因、瓦斯突出条件等分析了矿震与瓦斯突出相关的机理. 进一步介绍了瓦斯流体对矿震的触发作用,尤其超临界流体的特殊性质在矿震发生中的重要作用.依据矿震与构造地震在机制方面的相似性, 讨论了上述结果在震源物理研究中的意义. 相似文献
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京西矿震活动特征及其与天然地震关系初探 总被引:4,自引:0,他引:4
该文介绍了门头沟矿震的概况;对门头沟矿震与天然地震进行了相关分析,认为门头沟煤矿矿震活动可作为一种较好的监视首都圈中西部强震的中尺度监测手段;论证了门头沟煤矿矿震活动作为首都圈地应力变化监测哨的地质依据,并初步建立了矿震作为地震前兆的力学模型;提供了矿震预测天然地震的地质依据。 相似文献
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矿震及其深井水位的异常响应车服务态度 总被引:1,自引:0,他引:1
简要介绍了山东省陶庄煤矿的二次矿震及其井水位的同震效应与震前异常。结果表明,矿震活动与天然地震活动在时间上有同步性,并且二次矿震的井水位同震效应形态与震前异常持续时间有差异,而这种差异主要同震源体的破坏特征有关。 相似文献
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煤矿井水位观测资料中微弱孕震信息的提取 总被引:2,自引:0,他引:2
采用自适应技术,从陶庄煤矿区鲁15井的水位观测资料中提取了ML=1-2矿震前微弱的前兆信息,为矿震预报提供了有用方法。 相似文献
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矿区震动能诱发多种灾害,以瓦斯突出尤为严重。以鹤岗矿区为研究对象,统计了历年来鹤岗地区地震及矿震活动规模,分析了以往典型的矿震引起的瓦斯灾害事例,总结了矿震作用下瓦斯灾害的机理,基于统计数据,提出了矿震瓦斯灾害预警需要解决的关键问题。初步研究表明:震动事件与煤矿灾害之间具有很强的关联性,呈现震动在前、灾害在后、时间间隔数分钟至数日不等的“先震后灾”的特点,基于此,通过建立矿震监测台网,给出了震动诱发煤矿瓦斯灾害预警可行性,并提出了震动引起瓦斯灾害预警思路。 相似文献
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Geotomographic imaging in the study of mining induced seismicity 总被引:1,自引:0,他引:1
R. P. Young D. A. Hutchins J. McGaughey J. Towers D. Jansen M. Bostock 《Pure and Applied Geophysics》1989,129(3-4):571-596
Geotomographic imaging is a technique which allows seismic waves to be used to gain information about the internal structure of rock masses, in a way conceptually similar to medical CAT scanning. Traditional approaches to the study of mining-induced seismic phenomena have concentrated on using passive monitoring methods. This paper gives an overview of the developments in the acquisition, processing and interpretation of geotomographic data and outlines how images can be used in conjunction with passive techniques to study mining-induced seismicity.Presented at the Fred Leighton Memorial Workshop on Mining Induced Seismicity, Montreal 1987. 相似文献
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G. J. Finnie 《Pure and Applied Geophysics》1999,154(1):41-56
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S. M. Hsiung W. Blake A. H. Chowdhury T. J. Williams 《Pure and Applied Geophysics》1992,139(3-4):741-762
The performance of an underground excavation at the Lucky Friday Mine that was subjected to repetitive episodes of mining-induced seismic activities is assessed. Field measurements indicate that an underground excavation may respond to mining-induced seismicity with step changes in displacement of the rock mass around the excavation or step changes in excavation closures. However, step changes in displacement or closure were also observed without the presence of mine seismic events. This behavior may be explained using the concept of stick-slip on joints or bedding planes within the rock mass. The stick-slip mechanism is believed to be controlled by the state of stresses at a joint or bedding plane. Through this mechanism, joint displacement is accumulated in a progressive fashion leading to a weakening of rock mass around an excavation. As a result, the excavation becomes less stable and therefore is more susceptible to seismic impacts. The concept of using peak particle velocity to assess damage threshold for underground excavations may not be conservative when considering the effect of rock mass fatigue. 相似文献
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煤矿冲击矿压现象日益严峻,作为矿山动力灾害的主要监测手段,微震监测系统已在许多矿井广泛使用,为保证矿震定位和能量计算的准确,提高预测预报煤矿冲击矿压的可行性,应建立一套台网布设优化及评价系统.应用微震定位和D值优化设计理论,结合煤矿实际条件研究了影响矿震定位精度的主要因素和不利条件,并提出了采用综合指数法确定煤矿高微震活动区域和区域内矿震发生的概率,制定了台站候选点和监测区域确定的一般原则.通过理论分析震中和震源标准差反映台网定位能力的不足,建立基于数值仿真实验方法的震中与震源误差期望值模型,最终形成台网布设优化及评价系统.实验和现场应用结果表明,该系统能够快速确定台网最优布设方案,准确评价台网定位能力,满足煤矿微震监测的需要. 相似文献
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This paper presents an overview of mining seismicity, gas outburst and their origin. The internal relation of mining seismicity and gas outburst in the dynamic process is studied on the basis of the fact that these disasters sometimes occur simultaneously. The examples show a close relationship between mining seismicity and gas outburst in high gassy coal mines. It is proposed that strong mine shocks plus the response of low value and delay time are early warning signals. The mechanism of the relationship between mining seismicity and gas outburst is analyzed by using the location of mining shocks, focus mechanism, cause of mining shocks and conditions of gas outburst. The trigger action of gas fluid on mining shocks, especially the effect of the anomalous property of supercritical fluid on the preparation and occurrence of mining shocks is discussed. According to the similarity between min-ing-induced earthquakes and tectonic earthquakes in terms of mechanism, the significance of the above results in the study of physics of earthquake source is also discussed. 相似文献
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Ivan G. Wong James R. Humphrey Janet A. Adams Walter J. Silva 《Pure and Applied Geophysics》1989,129(3-4):369-405
In the summer of 1984, a three-dimensional, high-resolution microearthquake network was operated in the vicinity of two coal mines beneath Gentry Mountain in the eastern Wasatch Plateau, Utah. During a six-week period, approximately 3,000 seismic events were observed of which the majority were impulsive, higher frequency (>10 Hz), short duration (<2–3 sec) events probably associated with the caving of the roof from a longwall operation. In contrast, 234 of the largest located events appeared to occur predominantlybeneath the mines to a depth of 2 to 3 km consistent with previous studies. The magnitudes of these events ranged from less thanM
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0 to 1.6. In addition to the unusual depths of these latter events, an anomalous aspect displayed by the events was an apparent dilatational focal mechanism suggesting a non-double-couple, possibly implosional source. Implosional events have been observed in other studies of mine seismicity; however, the generally inadequate instrumental coverage of the focal sphere has cast some doubt on the validity of such mechanisms. Previously suggested source mechanisms for such implosional events have included tensional failure through strata collapse, and a shear-implosional displacement mechanism. Shear failure must be involved in the failure process of the Gentry Mountain implosional events as evidenced by well-defined shear waves in the observed seismograms. Simultaneous monitoring in the East Mountain coal mining area to the south by the University of Utah revealed typical shear failure events mixed with implosional events. The observed double-couple, reverse focal mechanisms at East Mountain were similar to mechanisms determined in previous studies and a composite focal mechanism determined in this study for a sequence outside the mining areas. This suggested that the shear events within the mining areas are being influenced by the regional tectonic stress field. Thus in addition to the seismic events associated with caving of the roof from the longwall operation, there appear to be at least two other types of mining-induced seismic events occurring in the eastern Wasatch Plateau, both submine in origin: (1) events characterized by apparent non-double-couple possibly implosional focal mechanisms and well-defined shear waves; and (2) shear events, which are indistinguishable from tectonic earthquakes and may be considered mining triggered earthquakes. The small mining-induced stress changes that occur beyond a few hundred meters from the mine workings suggest both types of seismic events are occurring on critically stressed, pre-existing zones of weakness. Topography, overburden, method of mining, and mine configuration also appear to be significant factors influencing the occurrence of the implosional submine events. 相似文献
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《Journal of Geodynamics》2003,35(1-2):173-189
The special type of intraplate microseismicity with swarm-like occurrence of earthquakes within the Vogtland/NW-Bohemian Region is analysed to reveal the nature and the origin of the seismogenic regime. The long-term data set of continuous seismic monitoring since 1962, including more than 26000 events within a range of about 5 units of local magnitude, provides an unique database for statistical investigations. Most earthquakes occur in narrow hypocentral volumes (clusters) within the lower part of the upper crust, but also single event occurrence outside of spatial clusters is observed. Temporal distribution of events is concentrated in clusters (swarms), which last some days until few month in dependence of intensity. Since 1962 three strong swarms occurred (1962, 1985/86, 2000), including two seismic cycles. Spatial clusters are distributed along a fault system of regional extension (Leipzig-Regensburger Störung), which is supposed to act as the joint tectonic fracture zone for the whole seismogenic region. Seismicity is analysed by fractal analysis, suggesting a unifractal behaviour of seismicity and uniform character of seismotectonic regime for the whole region. A tendency of decreasing fractal dimension values is observed for temporal distribution of earthquakes, indicating an increasing degree of temporal clustering from swarm to swarm. Following the idea of earthquake triggering by magma intrusions and related fluid and gas release into the tectonically pre-stressed parts of the crust, a steady increased intensity of intrusion and/or fluid and gas release might account for that observation. Additionally, seismic parameters for Vogtland/NW-Bohemia intraplate seismicity are compared with an adequate data set of mining-induced seismicity in a nearby mine of Lubin/Poland and with synthetic data sets to evaluate parameter estimation. Due to different seismogenic regime of tectonic and induced seismicity, significant differences between b-values and temporal dimension values are observed. Most significant for intraplate seismicity are relatively low fractal dimension values for temporal distribution. That observation reflects the strong degree of temporal earthquake clustering, which might explain the episodic character of earthquake swarms and support the idea of push-like triggering of earthquake avalanches by intruding magma. 相似文献
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Effect of the Rock Properties on Mining-induced Seismicity Around the Ventersdorp Contact Reef, Witwatersrand Basin, South Africa 总被引:1,自引:0,他引:1
—?The Ventersdorp Contact Reef is characterised by a variety of different rock types that are found above and below the reef in different mining areas. These variations in the host rock type have been classified into six main geotechnical areas. Knowledge of the difference in seismicity related to these geotechnical areas could influence the design of deep level stopes and optimise the support systems.¶In this study, the total seismicity was evaluated using the relationship between the cumulative seismic moment and volume of convergence. In total 300,000 seismic events, occurred at Deelkraal, Elandsrand, East Driefontein, Kloof and Leeudoorn mines. Kloof and Leeudoorn gold mines were divisions of Kloof Gold Mine Co. Ltd. Mponeng was previously called Western Deep Levels Ltd.-South Mine.¶The seismicity generated in areas with different mining conditions and geology has been compared. Special attention was paid to evaluate the difference in seismicity associated with different geotechnical classifications. The following variations were found: (i) geotechnical areas with soft (Westonaria) lava hangingwall and quartzite-conglomerate footwall are less active than the geotechnical areas with hard (Alberton) lava hangingwall and quartzite-conglomerate footwall at East Driefontein, Kloof and Leeudoorn Mines, (ii) geotechnical areas with soft lava hangingwall and Jeppestown Shale footwall are less active than geotechnical areas with soft lava hangingwall and quartzite-conglomerate footwall at East Driefontein Mine, (iii) geotechnical areas with hard lava hangingwall and quartzite-conglomerate footwall and hard lava hangingwall and Booysen's Shale footwall at Western Deep Levels-South Mine do not indicate differences in the associated seismicity, (iv) the variations in the properties of the different types of quartzite forming the footwall at Deelkraal, Elandsrand, Mponeng, East Driefontein and Kloof Gold Mines do not appear to influence the level of seismicity. 相似文献