6 results about "Transverse isotropy" patented technology

A method that includes disposing an acoustic logging tool in a borehole. The acoustic logging tool comprises one or more transmitters and one or more receivers. The method may further comprise taking one or more acquisitions with the acoustic logging tool as the acoustic logging tool traverses through the borehole, creating an azimuth rotation angle array of one or more angles, from the one or more acquisitions, and applying a trial angle selected from the one or more angles of the azimuth rotation angle array to calculate a fast shear waveform.

The invention discloses a seismic four-parameter linear direct inversion method based on a transverse isotropic medium reflection coefficient precision formula, and belongs to the technical field of unconventional reservoir seismic exploration. According to the method, an accurate Graebner reflection coefficient equation is deduced again, four pseudo-stiffness coefficients are introduced to re-characterize the reflection coefficient, and the number of to-be-inverted parameters is reduced from 5 to 4, so that the discomfort of an inverse problem is reduced. In order to improve the calculation efficiency of inversion, the partial derivative of the positive operator after the density item is eliminated is deduced to realize linear inversion of four parameters. In order to improve the precision of anisotropy parameter estimation, an indirect inversion strategy is adopted, four pseudo-stiffness coefficients are obtained through inversion, and then the anisotropy parameters epsilon and delta are estimated through inversion results. The feasibility of the inversion method is verified through a synthetic data test.

This application provides a method, device, and storage medium for predicting fracture density based on azimuth anisotropy, belonging to the field of geophysical research technology. The method includes: substituting fracture-related test data into a prediction formula to calculate the P-wave reflection coefficient. The prediction formula is an approximate formula for the P-wave reflection coefficient of a transversely isotropic medium, and the right-hand side variable of the prediction formula includes at least the fracture density in different directions; extracting well-side seismic trace data from azimuth-based stacked traces and deconvolving it to obtain a seismic wavelet; calculating the P-wave reflection coefficient data volume of the target work area based on the seismic wavelet and azimuth-based stacked traces; and inverting the fracture density in different directions of the target work area using an interpolated initial model as a constraint. The above method is based on an improved prediction formula, whose right-hand side variable includes the fracture density in different directions, realizing direct inversion of fracture density, reducing inversion time and accumulated errors, and improving the efficiency and accuracy of fracture density prediction.

The invention discloses a DAS data image generation method and device for underground structure visualization. Comprising the following steps: constructing a three-dimensional coordinate system, and obtaining an original sound wave equation, a strain rate parameter and a seismic source parameter of a vertical and transverse isotropic medium; simplifying the strain-displacement relational expression to obtain a conversion relation between the axial strain rate and the velocity component; speed components in the original acoustic wave equation are replaced based on the conversion relation, and an anisotropic acoustic wave equation suitable for DAS data is constructed; deducing a seismic source wave field extrapolation equation and a detection point wave field extrapolation equation according to the anisotropic acoustic wave equation; respectively inputting the focus parameter and the strain rate parameter into corresponding extrapolation equations to obtain a focus pressure wave field and a detection point pressure wave field; and performing mutual-closing imaging processing on the two types of pressure wave fields to obtain an initial result, and performing optimization processing to obtain an underground structure imaging result of the target DAS data. According to the invention, the precision and reliability of DAS data underground structure imaging under complex geological conditions are improved.

A method that includes disposing an acoustic logging tool in a borehole. The acoustic logging tool comprises one or more transmitters and one or more receivers. The method may further comprise taking one or more acquisitions with the acoustic logging tool as the acoustic logging tool traverses through the borehole, creating an azimuth rotation angle array of one or more angles, from the one or more acquisitions, and applying a trial angle selected from the one or more angles of the azimuth rotation angle array to calculate a fast shear waveform.

The present application relates to the technical field of oil exploration, and more particularly to a method and system for modeling earth stress based on transverse isotropy; comprising the following steps: S1, obtaining well logging data of a study area well, processing and correcting missing sections of the well logging data to obtain processed well logging data; S2, calculating formation pore pressure based on the processed well logging data obtained in step S1; S3, calculating elastic parameters of a transversely isotropic medium, the elastic parameters including Young's modulus and Poisson's ratio; S4, establishing an earth stress model according to the formation pore pressure obtained in step S2 and the elastic parameters obtained in step S3; the present application is suitable for high-precision earth stress calculation of super-deep drilling complex lithology.