High-resolution Seismic Data Processing Methods Based On Inverse Q-filter And IGST

In order to improve the resolution of seismic data and fully excavate the amplitude,frequency and phase information of different frequency components of the seismic data and further use them for high-resolution hydrocarbon detection and high-accuracy geological body description,high-resolution seismic data processing methods are studied for achieving the high-resolution reservoir architecture analysis.The main contents and results of the paper are as follows:(1)In order to obtain stable interval Q value,by analyzing the spectrum of monitoring wavelet and down-going direct wavelet of Zero-offset VSP data,this paper proposes a new expression of down-going direct wavelet spectrum.Basing on the new expression,this paper presents the amplitude spectral polynomial fitting and amplitude spectral ratio polynomial fitting methods for stable interval Q inversion based on Zero-offset VSP data.(2)A self-adaptive approach to optimize the Q value for the inverse Q-filter amplitude compensation based on the dynamic range of seismic data,the gain limit of the inverse Q-filter amplitude compensation,the inverse Q-filter amplitude compensation function and the medium quality factor.In the process of the inverse Q-filter amplitude compensation,the optimized Q value,corresponding gain limit and inverse Q-filter amplitude compensation function are used simultaneously;then,energy in the effective frequency band for the seismic data can be recovered,and seismic resolution can be enhanced at all times.Finally,we can obtain high-resolution and high signal-to-noise ratio seismic data.(3)Based on the dynamic range of the seismic data and medium quality factor,a self-adaptive method for inverse Q-filter amplitude compensation is proposed in this paper.The gain limit in the self-adaptive method is self-adaptive to the cut-off frequency of the effective frequency band for the seismic data,and the stabilizing factor changes in inverse proportion to the square of the self-adaptive gain limit.Then,it has the ability to completely restore energy in the effective frequency band for the seismic data,control the numerical instability of inverse Q-filter amplitude compensation and avoid the Gibbs effect,and finally achieves high-resolution and high signal-to-noise ratio seismic data.(4)Based on the generalized S transform and wavelet transform,the improved generalized S transform(IGST)is presented and used for hydrocarbon detection.IGST allows calculation the time-frequency instantaneous amplitude spectrum,time-frequency instantaneous phase spectrum and time-frequency initial phase spectrum of a signal with high-precision;with the IGST,we can obtain not only the time-frequency instantaneous amplitude spectrum,time-frequency instantaneous phase spectrum and time-frequency initial phase spectrum of high-frequency components with high time-resolution,but also the time-frequency instantaneous amplitude spectrum,time-frequency instantaneous phase spectrum and time-frequency initial phase spectrum of low-frequency components with high time-resolution.(5)Based on time-frequency instantaneous amplitude spectrum,time-frequency instantaneous phase spectrum and time-frequency initial phase spectrum obtained by IGST,the time-phase amplitude spectrum with high-resolution is proposed and used for edge detection.