Staggered-Grid Finite-Difference Wavefield Simulation and AVO Attribute Analysis Program for Dual-Phase Media

The Staggered-Grid Finite-Difference Wavefield Simulation and AVO Attribute Analysis Program for Dual-Phase Media serves as a critical tool in seismic exploration. This program primarily simulates elastic wave propagation patterns in dual-phase media (such as fluid-saturated porous rocks) and integrates AVO (Amplitude Versus Offset) attributes for reservoir characterization analysis.

Core Modules

Staggered-Grid Finite-Difference Algorithm The program employs high-precision staggered-grid finite-difference methods to effectively simulate seismic wave propagation in complex media. The staggered-grid approach optimizes traditional finite-difference schemes by improving numerical stability and reducing grid dispersion. The implementation supports differential operators of various accuracy orders through configurable stencil coefficients, allowing users to select appropriate computational precision based on specific requirements.

Eigenvalue Analysis-Based Boundary Absorption To minimize artifacts from artificial boundary reflections, the program implements absorbing boundary conditions using eigenvalue analysis methodology. This technique efficiently absorbs spurious reflected waves at boundaries through carefully designed damping layers, ensuring accurate wavefield simulation results. The code implements complex frequency-shifted perfectly matched layers (CFS-PML) for optimal absorption performance across different frequency ranges.

Dual-Phase Media Parameter Calculation The elastic parameter calculation module for dual-phase (solid-fluid) media is based on Biot theory. The algorithm processes key parameters including porosity, permeability, and fluid saturation, then computes equivalent elastic moduli and wave velocity distributions. The implementation features modular functions for calculating frequency-dependent velocity dispersion and attenuation effects characteristic of porous media.

AVO Attribute Analysis The program computes reflection coefficients at different offsets and extracts AVO attributes (such as intercept, gradient, and Poisson's ratio variations) for reservoir fluid identification and lithology prediction. The codebase supports multiple AVO approximation formulas including Aki-Richards and Shuey equations through switchable calculation modules. The implementation includes parallel processing capabilities for efficient AVO attribute extraction across large seismic datasets.

Applications and Extensions This program finds broad applications in hydrocarbon exploration and CO₂ geological sequestration monitoring. Future development pathways include integrating machine learning algorithms for parameter inversion optimization and extending capabilities to anisotropic dual-phase media simulation to further enhance accuracy. The modular architecture allows for straightforward integration of additional physical models and computational methods.