Hessian Vector Product in Transversely Isotropic Media
Description:
Full waveform inversion (FWI) is a powerful technique for imaging Earth’s subsurface structure at local, regional, and global scales, providing detailed reconstructions of geological features. However, a significant challenge in FWI is the trade-off between multiple parameters, which can lead to non-unique solutions and hinder accurate model updates (Fichtner et al., 2024). This trade-off issue is particularly important in seismic tomography, as the interplay of various parameters such as P-wave velocity, anisotropy, and subsurface heterogeneity can result in parameter cross-talk, complicating the interpretation of seismic data. Resolving these trade-offs is critical for improving the accuracy of seismic imaging and understanding the Earth’s subsurface dynamics.
The Hessian vector product (HVP) has been successfully used in acoustic and elastic FWI to mitigate parameter trade-offs, but its application in transversely isotropic (TI) media has been limited due to computational challenges and the large disk space and I/O requirements associated with storing and transforming wavefields during the inversion process. In this study, we derive the HVP in TI media using the adjoint-state method and compute it by combining the on-the-fly method with checkpointing, which reduces disk space and I/O demands. This development can be implemented through finite-difference or spectral element methods. The HVP is more sensitive to small-scale structures in the Earth model compared to the gradient and highlights its importance for refining Earth tomography models. This contributes to interpreting tomography models and understanding Earth's dynamic structural evolution at multiple scales, with potential implications for seismic hazard assessment and resource exploration due to the improvement in the accuracy and resolution of the models.
Session: Earth’s Structure from the Crust to the Core [Poster]
Type: Poster
Date: 4/16/2025
Presentation Time: 08:00 AM (local time)
Presenting Author: Yujiang
Student Presenter: No
Invited Presentation:
Poster Number: 111
Authors
Yujiang Xie Presenting Author yujiangxie@gmail.com University of Texas at Austin |
Mrinal K. Sen Corresponding Author mrinal@utexas.edu University of Texas at Austin |
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Hessian Vector Product in Transversely Isotropic Media
Category
Earth’s Structure from the Crust to the Core