矿井微震信号b值计算样本及参数选取研究

发布时间：2018-04-07 00:10

本文选题：微震信号b值　切入点：微震监测　出处：《煤炭科学技术》2016年12期

【摘要】：为提高矿井微震信号b值计算效率和准确性,以孟村矿井掘进期间实际发生微震事件为样本,围绕b值计算过程中所涉的样本及参数选取等问题开展研究。不同发震区域微震演化机制及规律不同,b值计算样本的选取应以发震区域为基本单位,发震区域的范围由内部所有发震单元的关联微震事件分布确定。低震级事件缺失导致b值计算结果大幅偏小,可通过分析相关系数变化趋势确定最佳起始震级。在设置最高档次震级时,应考虑样本高震级端的频次分布情况,使得最高档次对应的微震频次与其理论值相当,并保证推移时间窗过程中,非空档次总数不变。时间窗过短时,b值计算结果易受随机异常因素影响。而时间窗过长时,b值因早期历史数据影响过大而波动偏小,在时间序列上的可区分性差。相对于能量、频次曲线,b值变化曲线更加平稳,表现出阶段性的高(低)值区间,对高能事件的提示效果优于能量、频次曲线。
[Abstract]:In order to improve the efficiency and accuracy of calculating the b value of mine microseismic signals, taking the actual microseismic events in Mengcun mine excavation as the samples, the study is carried out on the selection of samples and parameters involved in the calculation of b values.The evolution mechanism and law of microearthquakes in different seismogenic regions are different. The selection of samples should be based on the seismogenic area, and the range of the seismogenic region should be determined by the distribution of the associated microseismic events of all the internal seismogenic units.The absence of low magnitude events results in a large decrease in the calculation result of b value. The optimum initial magnitude can be determined by analyzing the variation trend of correlation coefficient.When setting the maximum magnitude, the frequency distribution at the top of the sample with high magnitude should be taken into account, so that the frequency of the microearthquake corresponding to the highest grade is equivalent to its theoretical value, and the total number of non-empty grades should not be changed in the course of the time window.The calculated results of time window are easy to be influenced by random abnormal factors.However, when the time window is too long, the B value fluctuates little because of the influence of the early historical data, and the discriminability of the time series is poor.Compared with energy, the change curve of frequency curve B value is more stable, showing a periodic high (low) value range, the effect of high-energy events is better than that of energy, frequency curve.
【作者单位】：煤炭科学研究总院开采研究分院;天地科技股份有限公司开采设计事业部;
【基金】：国家重点研发计划资助项目(2016YFC0801401) 天地科技开采设计事业部青年创新基金资助项目(KJ-2015-TDKC-05)
【分类号】：TD324

【相似文献】