地震波传播速度原位试验及计算

Microseismic wave propagation velocity insitu experiment and calculation

采用本质安全型微震监测系统,在煤矿深部采场的顶底板中布设微震监测台网,对测区内的校验炮微震信号进行了原位采集实验。分别采用组合法、走时残差优化法、定位误差优化法、定位残差优化法和联合反演法进行了地震波速度的优化计算。通过计算结果的对比分析,认为定位误差优化法计算结果最可靠,定位残差优化法计算结果是不可靠的;这一结论对于缺少校验数据情况下的速度选取具有重要意义,也证明了在存在速度误差的情况下,走时残差最小并不能保证可靠的定位精度;在缺少原位试验数据情况下,速度和震源参数的联合反演结果,对速度参数的选取具有重要意义。通过对顶、底板地震波传播速度分析计算,认为煤层和巷道是造成底板地震波平均速度较低的原因。

With intrinsically safe microseismic monitoring system and geophones array in the roof and floor of deep coal mine,and based on calibration blast,a microseismic signal in-situ collecting experiment was performed.Several calculation methods such as：combination method,travel-time residuals optimization method,location error optimization method,location residual optimization method and the joint inversion method were applied on the optimization of seismic wave velocity calculation.Comparisons of the results show that the optimal location error result is the most reliable method,while the location residual optimization method is not reliable.This conclusion has great significance for the velocity selection on the conditions of lack of calibration data,and it also proves that it does not guarantee a reliable accuracy based on minimum travel-time residuals when velocity error exists.The joint inversion parameters of the velocity and source parameters will be suitable for velocity parameters determination when in-situ test data absence.Propagation velocity of the roof and floor were analyzed and calculated,it shows that coal layer and tunnels are the main factors cause the lower average seismic velocity of the floor.