Lithospheric Structures of the Central Cascadia Subduction Zone Resolved by Full-waveform Inversion of Ambient Noise and Receiver Functions
Description:
Lithospheric Structures of the Central Cascadia Subduction Zone Resolved by Full-waveform Inversion of Ambient Noise and Receiver Functions Nanqiao Du1, Bin He2,3, Ting Lei1, Tianshi Liu1, Qinya Liu1,2 1 Department of Earth Science, University of Toronto, Toronto, Canada 2 Department of Physics, University of Toronto, Toronto, Canada 3 Department of Geosciences, the University of Texas at Dallas, Richardson, TX, USA
The Cascadia subduction zone is one of the relatively young and warm endmember subduction systems, mainly due to the subduction of the Juan De Fuca plate underneath the North American Plate. Studies have shown the complex fluid migration processes in the crust and mantle while the tremor activity could also be partly attributed to fluid migration in this region. In this study, we aim to obtain high-resolution velocity structures of the crust and upper-mantle of this region based on full-waveform inversion. Particularly, high frequency P receiver functions (P-RF) are sensitive to sharp discontinuities and velocity variations beneath dense seismic arrays, and ambient noise data can be used to constrain fine-scale crustal structures. By using hybrid spectral element method (FK-SEM), we jointly invert could combine the P-RF waveforms and ambient noise cross-correlation data of the CASC93 array (Trehu et al., 1994) to obtain a detailed shear-wave velocity structure of the central Cascadia subduction Zone. Our model shows strong variations in the crust and upper-mantle in the central Cascadia subduction zone, and may further improve our understanding of the subduction and fluid migration processes geodynamics in this region.
Reference
Trehu, A., Asudeh, I., Brocher, T. M., Luetgert, J. H., Mooney, W. D., Nabelek, J., & Nakamura, Y. (1994). Crustal architecture of the Cascadia forearc. Science, 266(5183), 237-243.
Session: 3D Wavefield Simulations: From Seismic Imaging to Ground Motion Modelling [Poster Session]
Type: Poster
Date: 5/2/2024
Presentation Time: 08:00 AM (local time)
Presenting Author: Qinya
Student Presenter: Yes
Invited Presentation:
Authors
Nanqiao Du Corresponding Author nanqiao.du@mail.utoronto.ca University of Toronto |
Qinya Liu Presenting Author liuqy@physics.utoronto.ca University of Toronto |
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Lithospheric Structures of the Central Cascadia Subduction Zone Resolved by Full-waveform Inversion of Ambient Noise and Receiver Functions
Category
3D Wavefield Simulations: From Seismic Imaging to Ground Motion Modelling