Method and device for predicting relative impedance based on dipole seismic wavelet multiple integrals

Abstract

The invention discloses a method and device for predicting relative impedance based on dipole seismic wavelet multiple integrals. The method includes the first step of carrying out well logging and seismic joint calibration according to well logging and seismic data so as to extract wavelets and determine time depth relations, and extracting parameter characteristics of the top and bottom of a reservoir, the second step of building reservoir response characteristic wave functions of the dipole seismic wavelets according to the wavelets, the time depth relations and the parameter characteristics of the top and bottom of the reservoir, the third step of carrying out multiple integral operation on seismic sections according to the reservoir seismic response characteristic wave functions to extract and form a seismic response model database, and determining the best calculating integral multiple number and sliding window parameters, and the fourth step of carrying out the relative impedance operation on an actual seismic data volume according to the best calculating integral multiple number and the sliding window parameters to generate a relative impedance data volume. The method and device have the advantages that the integral characteristics of the seismic data are directly utilized to extract reservoir thickness characteristic parameters, the accuracy of reservoir seismic prediction is improved, and the effect for predicting the relative impedance of the reservoirs such as a carbonatite karst cave and sand shale is ideal.

Description

technical field [0001] The present invention relates to the field of petroleum geophysical exploration, in particular to a multiple seismic trace integration method using dipole seismic wavelets, and a prediction method that uses seismic profile information to perform continuous integration and accumulation from top to bottom into reservoir characteristic profiles, especially for The effect of relative impedance prediction for carbonate caves, sand-shale and other reservoirs is ideal. Background technique [0002] Petroleum geophysical exploration technology is one of the most widely used technical methods to find the spatial distribution and internal structure of oil and natural gas in underground reservoirs. The rock-acoustic characteristics recorded by seismic data are used to determine the lithology boundary of the reservoir instead of the stratum reservoir. A direct reflection of the characteristics of the set. It is of great significance to oil and gas exploration and...

AI Technical Summary

Problems solved by technology

[0018] In 2004, Wang Xiwen and other geophysical experts systematically analyzed the model-based well-constrained wave impedance inversion in the article "Multi-well Logging Parameter Inversion Method and Application Constrained by Relative Wave Impedance Data Volume", the core of which is forward inversion In combination, the main problems are: first, the establishment of the initial wave impedance model is based on experience, which leads to multi-solution; second, the inhomogeneity of the fitting degree between the synthetic seismic record and the wellside seismic record causes the phenomenon of modeling

Third, virtual wells are used to solve the problem of crossing faults. Virtual wells are usually set when faults are encountered during the inversion process. If the plugging characteristics of faults are not well understood, it is likely that the set virtual well position is wrong. thus affecting the inversion results

The disadvantage is: the absolute value of the wave impedance is not known

Therefore, the Dow integral (relative wave impedance) has a clear geological meaning, but due to the lack of depth in its research, it is rarely used in practical work, and the expression is not deep enough to study

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