Research On Thin Layer Inversion Method

Thin-layer reservoirs in China are rich in oil and gas resources,and thin-layer seismic inversion has extremely important practical significance.Whether the resolution of inversion results can achieve thin layer inversion depends mainly on the frequency range of seismic data itself.Conventional seismic data often lack reliable and valuable high-frequency information,and the inversion results will not achieve the accuracy of identifying thin layers.To this end,from the perspective of how to improve and obtain reliable and valuable high-frequency information,this paper uses seismic high-resolution processing techniques and high-precision Bayesian thin-layer inversion methods to achieve thin-layer inversion.Due to the viscoelastic properties of the underground medium,seismic waves inevitably suffer from amplitude attenuation and waveform distortion during propagation,resulting in reduced seismic resolution.Inverse Q filtering is a high-resolution seismic processing method that performs attenuation compensation on seismic signals and improves resolution.Inverse Q filtering is not only capable of completing amplitude compensation and phase correction,but more importantly,it can broaden the frequency band of seismic data and increase the energy of reliable high-frequency information carried by the seismic data itself,which is conducive to thin-layer seismic inversion.The high-precision Bayesian thin layer inversion method consists of multi-scale joint inversion and single-scale inversion.Bayesian multi-scale joint inversion integrates surface seismic data and cross-well seismic data together,which can adaptively adjust the weight of data at different scales,and effectively improves the inversion resolution by introducing reliable and valuable high-frequency information of cross-well seismic data.When the seismic coverage is not between wells,the joint inversion method degenerates into a single-scale inversion method,which can adaptively adjust regularization parameters,try to display the thin layer information contained in the seismic waveform to the greatest extent,and improve the inversion resolution.Applying the above method to an actual work area in the Bohai Bay,the overall effect is better than conventional inversion methods,and has achieved good results,indicating that the above method is feasible for thin layer inversion.