Research on identifying the airy phase of transmitted channel waves based on generalized S-transform
CHEN Bo1,2(), ZHU Guo-Wei1,2, WU Yan-Hui1,2, YANG Zhen-Qiang1,2, ZHOU Jun-Jie1,2
1. School of Geoscience and Surveying Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China 2. State Key Laboratory of Coal Resources and Safe Mining,China University of Mining and Technology(Beijing),Beijing 100083,China
Transmission seismic exploration in the coal mining face is one of the important geophysical surveys to figure out the geological hazards of coal seam.The rationality of identifying the airy phase from the transmitted channel waves is closely related to the accuracy of the tomography.Nowadays,S-transform is widely used in the analysis of dispersion curve,however,its application is limited with the fixed window.In order to improve the identification accuracy of the airy phase of the dispersion curve,this paper introduces the generalized S-transform with adjustable window into the analysis of dispersion curve.The window of generalized S-transform is analyzed by temporal full width at half maximum (temporal FWHM).For a frequency range,a wider window indicates a lower temporal resolution and a higher frequency resolution,and a narrower window indicates a higher temporal resolution and a lower frequency resolution.The time-frequency resolution can be adjusted quantitatively according to the relationship between the temporal FWHM and the parameters of generalized S-transform in application.The synthetic and real data result show that the generalized S-transform can effectively improve the time-frequency resolution and the airy phase characteristics of the dispersion curve.It is helpful for the interpreter to pick up the airy phase of the transmitted channel waves accurately.
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