3D Time-Domain Viscoelastic Anisotropic Seismic Wave Modeling using Subdomain Chebyshev Spatial Differentiation and Recursive Time Convolution

Abstract

The thesis focuses on the accurate and efficient numerical simulation of the 3D viscoelastic anisotropic wave equation in the time domain. The modeling can accommodate the various complex geological settings, including the irregular subsurface, the topographic free surface, and the fluid-solid interface, which helps migration and full waveform inversion of seismic data. To solve the tedious convolution part in the rheology model representing the viscoelastic effect, the generalized recursive convolution method is proposed, which owns better accuracy and efficiency than conventional auxiliary differential equation method. The high-order recursive convolution method is compared with the high order auxiliary differential equation method to show the superior performance under the framework of Adams–Bashforth integration. The subdomain Chebyshev spectral technique is developed for the spatial differentiation in the wave equation simulation. For the complex boundary, including free surface and fluid-solid boundary condition, we apply the traction image method to accurately process the boundary values. Numerical experiments verify the correctness and capability of the homogenous and heterogenous model, including Marmousi model, SEG Hess model and SEG/EAGE Overthrust model. Our holistic approach plays a crucial role in enhancing seismic exploration, subsurface imaging, and geohazard detection, which offers a powerful and efficient tool for achieving high-resolution imaging of the subsurface.

Date of Award	28 Nov 2024
Original language	American English
Supervisor	Mohammed Ali (Supervisor)