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矿震识别及成因研究进展 总被引：2，自引：0，他引：2
矿震主要受开采活动、矿山所处构造环境及区域构造应力场的影响。本文首先回顾了矿震的识别研究进展,然后从矿震震源机制、矿震与构造关系、矿震与瓦斯溢出、矿震与开采进程关系、矿震成因力学机制理论与实验研究等角度对矿震的成因研究进行了阐述,最后给出矿震识别及成因研究的进一步建议。矿震成因研究深化了对天然地震的认识。在研究矿震发生机理时,必须针对具体条件进行深入讨论与分析,应更多采用有关数学和力学手段,结合具体的生产地质条件和科学实验研究,有针对性地开展研究工作。可利用层析成像技术详细了解矿震演变过程,深化对地壳介质在应力作用下发生破裂或位错过程的认识,进而对矿震发震成因进行深入研究。 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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使用S变换对2010年淄博矿山地区发生的一组地震事件进行时频分析,并将其能量谱与典型的矿震和天然地震进行对比,结果表明：博山震群中,部分事件的主频率偏低,普遍能量衰减较快等特点符合一般矿震事件的特征,但这组事件的能量密度谱随频率轴的展布较宽,频率成分丰富等特点又与天然构造地震的特点一致.说明这组事件不同于一般由采矿作业引发的矿震活动,可能是由于煤层的采空区强烈改变地下岩层内的应力分布,其他人为活动诱发了与王母山断裂有关的浅层构造活动的结果. 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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1993年5月15日19时,北京矿务局房山煤矿矿井下6号地震台附近,在4分多钟内相继发生3次破坏性矿震,最大一次震级为2.3级（M0=1.51011Nm）．利用理论地震图分析得到,这3次矿震都是以倾向滑动为主,与在场人员目击到的高倾角煤层中大量煤块倾泻而下的现象一致．主震及其震前一系列事件的6号台近场记录与普通记录不同,不仅有高频振动,而且还有低频振动．用弹性波理论和近年来一系列关于地震破裂成核理论结果进行分析表明:低频振动可能是亚临界扩展向前推进时激发的长周期波,它是不可恢复的形变;高频振动则是矿震事件,它是脆性破裂辐射的波场．根据M＝2.3事件记录及其震前5.4ｓ出现的前震记录中低频振动优势频率推测,主震发生时孕震断裂端部扩容区体积迅速增大．震前20多天直到主震发生期间,震源过程主要特点如下:亚临界扩展多次出现,在此期间孕震断裂端部扩容区体积变化不大．亚临界扩展时不仅激发产生长周期波,也常同时诱发小事件的发生,亚临界扩展优势方向与主震的滑动方向基本一致． 相似文献
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分析了帕米尔强震活动对新疆地震活动的影响,认为帕米尔强震活动对新疆境内地震活动具有前兆意义;在各活动过程中,新疆境内强震活动在时空域中表现出较好的韵律性;标志震发生后的第1次强震活动位于天山地区将对其后的地震活动产生不同影响。 相似文献
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强矿震地球物理过程及短临阶段预测的研究 总被引：5，自引：0，他引：5
基于中尺度地震实验场高密度数字地震和前兆台网对抚顺老虎台矿两次强矿震进行连续的现场观测,用地震学方法和小波工具分析强矿震孕震过程采集到的数据,提取短临阶段的异常信息;用区域强震震源机制解、强矿震的震源机制解、极近场震源调查、震源高精度定位、现场绝对地应力测量、三维有限差分数值试验方法,分析强矿震的孕震应力场环境和震源机制;通过定量观察采矿与矿震活动的相关性,分析强矿震的直接诱发原因．提出地质构造环境、地应力场和采矿活动共同作用诱发强矿震的机理和局部应力场在孕育该震过程起主导作用、卸荷重力应力场抑或耦合了高压瓦斯的膨胀起主要诱发作用的观点;发现煤炭深部开采条件下,矿震和瓦斯存在密切的相关性,有可能存在一种开采卸荷和高压瓦斯气体膨胀耦合作用诱发的新型矿震——卸胀耦合型矿震;提取到震前短临阶段存在的b值、η值、频次、波速比等可信的地震学异常和定点潮汐形变前兆异常,对异常信息的提取方法和强矿震短临阶段的预测进行了探讨． 相似文献
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Rockburst is divided into two types, one is strain-type resulting from rock damage and another is sliding-type resulting from fault slip events. Triggering mine pillar rockburst mainly consists of two steps: the occurrence of shear-band and the application of disturbance. In this paper, mechanical model of mine pillar subjected to uniaxial compression is established. By simplifying the complete stress–strain curve and the crack propagation behaviour, based on the derived energy expressions corresponding to different crack propagation stages, the type of rockburst that the disturbance-induced pillar instability belongs to is defined. Next, by establishing the model of mine pillar with one inclined shear-band and by simplifying the stress evolution on the band, based on the necessary physical characteristics for triggering dynamic events, the basic mechanical property of mine pillar required for triggering instability is derived. It shows that the post-peak modulus greater than or equal to the pre-peak modulus is the basic mechanical property required for triggering mine pillar instability. Finally, by conducting laboratory experiments, the proposed model is verified. The requirement that the post-peak modulus is greater than or equal to the pre-peak modulus may be the reason why triggered mine pillar rockburst is not often observed. 相似文献
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Possible mechanism of rockbursts in coal mines 总被引：1，自引：0，他引：1
One of the important questions of rockburst prevention is the understanding of the mechanism of rockburst source. This question can be effectively studied by direct seismic observations in the rockburst regions. For this purpose, the distribution ofP-wave onset signs and the inversion of first motion amplitudes were utilized as the basic method. In such a way the coal mine regions in Poland (Upper Silesia) and in Czechoslovakia (Kladno coal mine district) were studied as part of the Polish-Czechoslovak rockburst investigation project. More than 250 rockburst events were recorded here in the decade 1977–1983, and analyzed. The results of the statistical analysis of these data allow us to formulate and introduce a model of the rockburst source with an implosion component. The suitability of this conception was verified by laboratory simulation conditions; it was confirmed that the seismoactive displacements with a clear implosive component were recorded in the neighbourhood of a stress concentrator weakened by holes. The results of both the field observations and laboratory tests were in good agreement with the theoretically derived radiation patterns for a combined shear-implosive source and also with the theoretical conception of such a source based on real geometrical configurations of mine excavations and tectonic dislocations.The rockbursts treated exhibit a dominant shear component, the magnitude of the additional implosive component not exceeding 10 percent of the shear component. 相似文献
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Due to the complex mechanisms of rockburst, there is no current effective method to reliably predict these events. A statistical learning method, support vector machine (SVM), is employed in this paper for kimberlite burst prediction. Four indicators \(\sigma_{\theta } ,\sigma_{c} ,\sigma_{t} ,W_{\text{ET}}\) are chosen as input indices for the SVM, which is trained using 108 groups of rockburst cases from around the world. Data uniformization is used to avoid negative impact of differing dimensions across the original data. Parameter optimization is embedded in the training process of the SVM to achieve optimized predictive ability. After training and optimization, the SVM reaches an accuracy of 95% in rock burst prediction for validation samples. The constructed SVM is then employed in kimberlite burst liability evaluation. The model indicated a moderate burst risk, which matches observed instances of rockburst at a diamond mine in north Canada. The SVM method ignores the focus on rockburst mechanisms, instead relying on representative indicators to develop a predictive model through self-learning. The prediction results show an excellent accuracy, which means this method has a potential application in rockburst prediction. 相似文献
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Calculation of Electromagnetic Radiation Criterion for Rockburst Hazard Forecast in Coal Mines 总被引：4，自引：0，他引：4
V. Frid 《Pure and Applied Geophysics》2001,158(5-6):931-944
— Intensive micro-fracturing of rock close to mining operations accompanies an increase in the likelihood of rockbursting. This fracturing causes an increase of the electromagnetic radiation (EMR) level by up two orders of magnitude, depending on the mining environment. Several examples of this enhanced EMR are presented in this paper. We first treat the EMR theoretical criterion of rockburst hazard in coal mines and compare it with the empirical criterion of EMR activity that was revealed on the basis of more than 400 different hazardous and non-hazardous situations in underground coal mines. Only the following parameters are needed to estimate the EMR criterion of rockburst hazard: limiting value of gum volume, mine working width, coal seam thickness, and coal elastic properties. 相似文献
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Navid Hosseini 《Journal of Seismology》2017,21(5):1101-1110
Rockburst is a typical dynamic disaster in underground coal mines which its occurrences relate to the mechanical quality of coal seam and surrounding rock mass and also the condition of stress distribution. The main aim of this paper is to study the potential of rockburst in a longwall coal mine by using of passive seismic velocity tomography and image subtraction technique. For this purpose, first by mounting an array of receivers on the surface above the active panel, the mining-induced seismic data as a passive source for several continuous days were recorded. Then, the three-dimensional tomograms using simultaneous iteration reconstruction technique (SIRT) for each day are created and by employing the velocity filtering, the overstressed zones are detected. In addition, the two-dimensional seismic velocity tomograms in coal seam level by slicing the three-dimensional tomograms are obtained. Then the state of stress changes in successive days by applying the image subtraction technique on these two-dimensional tomograms is considered. The results show that the compilation of filtered three-dimensional tomograms and subtracted images is an appropriate approach for detecting the overstressed zones around the panel and subsequent evaluation of rockburst potential. The research conclusion proves that the applied approach in this study in combination with field observations of rock mass status can effectively identify the rockburst-prone areas during the mining operation and help to improve the safety condition. 相似文献
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Jing Li Si-Yuan Gong Jiang He Wu Cai Guang-An Zhu Chang-Bin Wang Tian Chen 《Acta Geophysica》2017,65(1):77-88
A better understanding of rockburst precursors and high stress distribution characteristics can allow for higher extraction efficiency with reduced safety concerns. Taking the rockburst that occurred on 30 January 2015 in the Sanhejian Coal Mine, Jiangsu Province, China, as an example, the mechanism of rockburst development in a roadway was analysed, and a combined method involving b values and seismic velocity tomography was used to assess the rockburst in both time and space, respectively. The results indicate that before the rockburst, b values dropped significantly from 0.829 to 0.373. Moreover, a good agreement between a significant decrease in b values and the increase of the number of strong tremors was found. Using seismic tomography, two rockburst risk areas were determined where the maximum velocity, maximum velocity anomaly and maximum velocity gradient anomaly were 6 km/s, 0.14 and 0.13, respectively. The high-velocity regions corresponded well with the rockburst zone and large seismic event distributions. The combination of b values and seismic tomography is proven to have been a promising tool for use in evaluating rockburst risk during underground coal mining. 相似文献
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For years, severe rockburst problems at the Lucky Friday mine in northern Idaho have been a persistent safety hazard and an impediment to production. An MP250 based microseismic monitoring system, which uses simple voltage threshold picking of first arrivals, has been used in this mine since 1973 to provide source locations and energy estimates of seismic events. Recently, interest has been expressed in developing a whole waveform microseismic monitoring system for the mine to provide more accurate source locations and information about source characteristics. For this study, we have developed a prototype whole-waveform microseismic monitoring system based on a 80386 computer equipped with a 50 kHz analog-digital convertor board. The software developed includes a data collection program, a data analysis program, and an event detection program. Whole-waveform data collected and analyzed using this system during a three-day test have been employed to investigate sources of error in the hypocenter location process and to develop an automatic phase picker appropriate for microseismic events.Comparison of hypocenter estimates produced by the MP250 system to those produced by the whole-waveform system shows that significant timing errors are common in the MP250 system and that these errors caused a large part of the scatter evident in the daily activity plots produced at the mine. Simulations and analysis of blast data show that analytical control over the solutions is strongly influenced by the array geometry. Within the geophone array, large errors in the velocity model or moderate timing errors may result in small changes in the solution, but outside the array, the solution is very sensitive to small changes in the data.Our whole-waveform detection program picks event onset times and determines event durations by analysis of a segmented envelope function (SEF) derived from the microseismic signal. The detection program has been tested by comparing its arrival time picks to those generated by human analysis of the data set. The program picked 87% of the channels that were picked by hand with a standard error of 0.75 milliseconds. Source locations calculated using times provided by our entire waveform detection program were similar to those calculated using hand-picked arrival times. In particular, they show far less scatter than source locations calculated using arrival times based on simple voltage threshold picking of first arrivals. 相似文献