基于广义S变换的煤系断层槽波信号时频分析

Analysis on time-frequency of coal measures chasm signals based on generalized S transform

介绍了槽波地震勘探是一种利用煤层中传播的槽波对煤层异常构造进行精细探查的有效方法。为分析断层对槽波信号的影响,以用于断层预测及定位,在comsol 5.2中建立了三维煤系地层模型及断层模型,用主频200Hz的雷克子波作为震源激发得到携带断层信息的槽波信号,用广义S变换对信号进行时频分析,得出断层会削减槽波信号的振幅,导致部分频率能量缺失或迁移,当断层断距小于煤厚时对频散曲线影响不大。

In-seam Seismic Survey is an effective method for carefully investigate the abnormal structures of coal seam by using the channel wave propagating in coal seam. To analyze the influence of chasms on the channel wave and for its application in prediction and location of chasms,a three-dimensional coal-bearing strata model and a chasm model are established in comsol 5. 2. Using the Ricker wave with frequency of 200 Hz as the source excitation,channel wave signals carrying chasm information are obtained. Generalized S transform is adopted for the analysis on time-frequency of the signals,which shows that the chasms will reduce the amplitude of the channel wave,resulting in the loss of partial frequency energy. When the gap of chasms is smaller than the thickness of coal seam,the dispersion curve will not be affected.