An accurate and efficient numerical method for 2.5D time-domain viscoacoutic and viscoelastic wave modeling

Accurately modeling seismic wave propagation in complex subsurface geologic structures is crucial for understanding their properties. However, 3D seismic wave modeling can be computationally demanding, requiring a significant amount of computer memory and runtime. To address this issue, a more efficient and accurate approach known as 2.5D modeling can be used when the subsurface geologic structure is two dimensions. We develop a new numerical method for 2.5D time-domain viscoelastic wave modeling characterized by the subdomain Chebyshev differentiation for accurate spatial derivatives, a Taylor-series recursive approach for accurate computations of temporal convolutions, a novel transform of the complex-domain computations into real-domain implementation, and fully parallel computing for high computational efficiency. Comparing our results with 3D analytical and numerical reference solutions, we demonstrate that our method offers satisfactory accuracies, excellent computational efficiencies, and a powerful capability of modeling 3D wavefields in complex 2D heterogeneous viscoacoustic and viscoelastic geologic models. Overall, our findings provide a robust and efficient approach for modeling seismic wave propagation in complex 2D subsurface geologic structures.