A post-stack acoustic impedance inversion method

Abstract

The invention provides a post-stack acoustic wave impedance inversion method, which belongs to the field of seismic exploration and development of oil and gas and coalbed methane. The method includes: (1) processing the post-stack seismic data so that the frequency spectrum of the post-stack seismic data matches the frequency spectrum of the acoustic impedance obtained from the logging data, thereby obtaining relative acoustic impedance data; (2) constructing a method based on The initial acoustic impedance model or variogram of model inversion; (3) perform forward modeling calculation on the initial acoustic impedance model obtained in step (2) to obtain synthetic seismic data; (4) compare the synthetic seismic data with the actual post-stack seismic data Comparing, obtaining the modification amount of the acoustic impedance model, using the modification amount to modify and update the initial acoustic impedance model to obtain the updated acoustic impedance model, and then performing forward modeling calculation on the updated acoustic impedance model to obtain synthetic seismic data; As the initial acoustic impedance model, repeat step (4) to obtain the final inversion result.

Description

technical field [0001] The invention belongs to the field of seismic exploration and development of oil and gas and coalbed methane, and in particular relates to a post-stack acoustic wave impedance inversion method. Background technique [0002] With the needs of oil and gas exploration and development, more and more attention has been paid to reservoir prediction and fine description. There are more and more explorations and researches around this purpose, and seismic inversion is the most important point. When the target of inversion is wave impedance, it is called wave impedance inversion. The current seismic wave impedance inversion can be divided into post-stack inversion and pre-stack inversion according to the data used, and can be divided into direct inversion and indirect inversion according to the inversion method. Direct inversion is to start directly from the seismic data and perform calculations to obtain the acoustic impedance. Indirect inversion starts fro...

AI Technical Summary

Problems solved by technology

However, interpreting horizons directly from post-stack seismic data has low resolution on the one hand, and is also affected by the quality of seismic data on the other hand.

Although the stochastic inversion widely used at present can provide multiple models that meet the requirements of statistical parameters through geostatistical means, its lateral variogram is still affected by the quality of post-stack seismic data, that is, the measurement used to calculate the longitudinal variogram The resolution of the well and geological data does not match the resolution of the seismic data used to calculate the lateral variogram

Images