Method and device for predicting transverse wave speed of seismic rock

Abstract

The invention discloses a method and a device for predicting a transverse wave speed of a seismic rock. The method comprises the steps of acquiring logging data of the seismic rock; determining an equivalent volume modulus of a rock matrix by using an SCA model based on the logging data; determining a shear modulus of the rock matrix by using the SCA model based on the logging data; determining anequivalent volume modulus of a pore fluid based on the logging data; determining an effective pressure of the rock matrix based on the logging data; determining the pore stiffness based on a linear relation between a ratio k of the pore stiffness to the equivalent volume modulus of the rock matrix, and the effective pressure; based on the equivalent volume modulus of the rock matrix, the equivalent volume modulus of the pore fluid, the pore stiffness and the porosity, determining an equivalent volume modulus of a saturated rock through a Gassmann fluid replacement model; and based on the equivalent volume modulus of the saturated rock and the shear modulus of the rock matrix, determining a longitudinal wave speed and the transverse wave speed of the saturated rock. The influence of the effective pressure is introduced in modeling, so that the accuracy is improved.

Description

technical field [0001] The invention relates to the technical field of seismic rock analysis, in particular to a method and device for predicting shear wave velocity of seismic rock. Background technique [0002] The effective pressure is the difference between the confining pressure of the rock and its pore pressure, and is an important factor affecting the rock modulus and the velocity of compressional and shear waves. Rock physical modeling is an important means of seismic rock physics research, which can guide the study of reservoir characteristics and the exploration and development of oil and gas resources. The petrophysical model is an equivalent approximation to complex rocks based on the two-phase medium and equivalent medium theory, so as to carry out subsequent petrophysical analysis. The accuracy of the rock physics model determines the correctness of the rock physics analysis results, which in turn affects the accuracy of shear wave prediction and pre-stack inv...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a method and device for predicting seismic rock shear wave velocity, which is used to solve the technical problem that the rock physics modeling method in the prior art does not consider the influence of effective pressure on rock modulus and longitudinal and shear wave velocity

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