Study On The Multiwave And Multicomponent Advanced Imaging Method Based On Generalized S-transform Polarization Analysis

Faults are important hidden hazards for major disasters such as roadway heading,roof inrush,coal and gas outburst.The seismic wave method is less affected by interference,and is most suitable for predicting structural anomalies such as faults in front of the roadway.However,the conditions of coal roadway conditions are complex,the lateral offset is extremely small,and conventional migration imaging methods are difficult to accurately build fault models;therefore,the multi-wave multi-component polarization analysis study is a basic study of three-dimensional seismic wave field characteristics and fine imaging of faults in front of coal roadways.It has important theoretical significance and practical value for practical application.Based on the polarization characteristics of the diffracted waves in the coal seam in front of the coal roadway in the time-frequency domain,the theoretical analysis,numerical simulation,and field test are used as the research methods,and the research goal is to achieve the fine detection of the coal seam in front of the coal roadway.The following research results:(1)The characteristics of effective wave difference between normal and reverse faults in front of coal lane are revealed.During reverse fault detection,the diffracted waves of the lost-wing coal seam arrive at the detector before the reflected waves of the coal-seam fault location.Two types of fault characteristic waves are easily identified in the time domain,and then the polarization analysis and separation of the diffracted wave of the lost-wing coal seam It is easy to realize accurately;during normal faults,various reflected waves at the position where the coal seam is diffracted will reach the detector after the diffracted waves of the coal seam are lost,and will overlap with various reflected waves of the fault,and the diffracted waves of the winged coal seam will be polarized Analysis and separation are difficult.(2)A migration imaging method for high-precision positioning of broken wing coal seam in front of coal lane is proposed.This method uses generalized S-transform polarization analysis to calculate the polarization parameters of diffracted waves in broken wing coal seams,and uses the combination of geophones to calculate the possible diffraction points and uses the spatial density distribution as a standard to measure the broken wing coal seams in front of the coal roadway.Perform convergence imaging.(3)Diffraction wave imaging based on generalized S-transform time-frequency polarization analysis requires high accuracy of polarization parameters.When the polarization parameters are accurate,the imaging results are accurate;when there are deviations in the polarization parameters,it needs to be combined with other Tomographic characteristic waves can be accurately imaged by joint imaging.(4)Realized the quantitative detection of coal roadway faults in typical mining areas.Field tests were carried out in typical mining areas,and an advanced fault detection model was constructed.The empirical results show that the multi-wave and multi-component advanced imaging method based on generalized S-transform polarization analysis can provide the necessary technical parameters for the safe driving of coal roadways.