Research On The Key Technology Of High Resolution Processing For Urban Shallow Seismic Data

With the construction of China's infrastructure and the exploitation of shallow underground space in the city,more attention has been paid to the understanding of the composition of shallow geological structures.Seismic exploration technology is a commonly used effective and economical shallow geological exploration method.In order to enhance the accuracy of seismic exploration,it is necessary to finely process shallow seismic exploration data to achieve high signal-to-noise ratio and highresolution effects.Ultimately,it can accurately image.The surface environment of urban areas is complex,the measurement network is irregularly arranged,the coverage times are low,and the horizontal media of shallow media changes greatly.The static correction problem is serious,the interference factors are more,the noise components are complex,the abnormal interference is serious,and the surface soil loosens the high frequency attenuation.Serious,low frequency,narrow frequency band,it is difficult to achieve high resolution and high signal to noise ratio in actual processing.Based on the characteristics of shallow geological features and seismic data,this paper studies joint static correction technology,sub-offset multi-domain joint noise suppression technology and high-resolution processing technology suitable for urban shallow seismic data processing.In order to solve the static correction problem,firstly,techniques such as elevation static correction,refraction static correction and tomographic static correction are tested to eliminate the long-wavelength static correction amount,and then the interactive iterative static correction and the reflected wave residual static correction are eliminated to eliminate the short-wavelength static correction amount.For the problem of low signal-to-noise ratio,according to the relationship between offset and coverage,incident angle,signal-to-noise ratio,and near and far-off noise characteristics,the data is sorted into three paths: near,medium and far.Set,multi-domain joint noise suppression for three gathers.Design targeted denoising scheme,firstly process the near and far biased data to obtain the active components,then use the near and far biased data noise component feature analysis and denoising method test,combined with various denoising techniques to deal with the partial bias data,and finally Near,medium and far data reconstruction after denoising.High-resolution processing of denoised data,first using surface consistency deconvolution for wavelet compression,and then using predictive deconvolution to improve resolution,by iterative testing and optimization of prediction step size,improve shallow layer The resolution of the data.The practical application results of multiple target work areas show that the method is stable and reliable,can effectively improve the processing effect of shallow seismic data in the city,and further enhance the data resolution and signal-to-noise ratio effect,and finally obtain the high quality profile.Accurate and reliable shallow seismic data processing results provide favorable data support for the subsequent development and utilization of shallow space in cities.