@article {ashraf_high-resolution_2025,
	title = {A High-Resolution 3-D P-Wave Velocity Structure of the South-Central Cascadia Subduction Zone From Wide-Angle Shore-Crossing Seismic Refraction Data},
	journal = {Journal of Geophysical Research: Solid Earth},
	volume = {130},
	number = {2},
	year = {2025},
	note = {_eprint: https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2024JB029525},
	pages = {e2024JB029525},
	abstract = {Abstract This study addresses a significant gap in understanding the features of the south-central Cascadia subduction zone, a region characterized by complex geologic, tectonic, and seismic transitions both offshore and onshore. Unlike other segments along this margin, this area lacks a 3-D velocity model to delineate its structural and geological features on a fine scale. To address this void, we developed a high-resolution 3-D P-wave velocity model using active source seismic data from ship-borne seismic shots recorded on temporary and permanent onshore seismic stations and ocean-bottom seismometers. Our model shows velocity variations across the region with distinct velocity-depth profiles for the Siletz, Franciscan, and Klamath terranes in the overlying plate. We identified seaward dipping high-velocity static backstops associated with the Siletz and Klamath terranes, situated near the shoreline and further inland, respectively. Regions of reduced crustal velocity are associated with crustal faults. Moreover, there is significant along-strike depth variation in the subducting slab, which is about 4 km deeper near the thick, dense Siletz terrane and becomes shallower near the predominantly less-dense Franciscan terrane. This highlights a sudden tectonic and geologic transition at the southern boundary of the Siletz terrane. Our velocity model also indicates slightly increased hydration, though still minimal, in both the oceanic crust and the upper mantle of the subducting plate compared to other parts of the margin.},
	doi = {https://doi.org/10.1029/2024JB029525},
	author = {Ashraf, Asif and Hooft, Emilie E. E. and Toomey, Douglas R. and Tr{\'e}hu, Anne M. and Nolan, Sarah and Wirth, Erin A. and Ward, Kevin M.}
}
@article {paulatto_advances_2022,
	title = {Advances in seismic imaging of magma and crystal mush},
	journal = {Frontiers in Earth Science},
	volume = {10},
	year = {2022},
	month = {10/2022},
	abstract = {Seismic imaging methods have provided detailed three-dimensional constraints on the physical properties of magmatic systems leading to invaluable insight into the storage, differentiation and dynamics of magma. These constraints have been crucial to the development of our modern understanding of magmatic systems. However, there are still outstanding knowledge gaps resulting from the challenges inherent in seismic imaging of volcanoes. These challenges stem from the complex physics of wave propagation across highly heterogeneous low-velocity anomalies associated with magma reservoirs. Ray-based seismic imaging methods such as travel-time and surface-wave tomography lead to under-recovery of such velocity anomalies and to under-estimation of melt fractions. This review aims to help the volcanologist to fully utilize the insights gained from seismic imaging and account for the resolution limits. We summarize the advantages and limitations of the most common imaging methods and propose best practices for their implementation and the quantitative interpretation of low-velocity anomalies. We constructed and analysed a database of 277 seismic imaging studies at 78 arc, hotspot and continental rift volcanoes. Each study is accompanied by information about the seismic source, part of the wavefield used, imaging method, any detected low-velocity zones, and estimated melt fraction. Thirty nine studies attempted to estimate melt fractions at 22 different volcanoes. Only five studies have found evidence of melt storage at melt fractions above the critical porosity that separates crystal mush from mobile magma. The median reported melt fraction is 13\% suggesting that magma storage is dominated by low-melt fraction crystal mush. However, due to the limits of seismic resolution, the seismological evidence does not rule out the presence of small (<10~km3) and medium-sized (<100~km3) high-melt fraction magma chambers at many of the studied volcanoes. The combination of multiple tomographic imaging methods and the wider adoption of methods that use more of the seismic wavefield than the first arriving travel-times, promise to overcome some of the limitations of seismic tomography and provide more reliable constraints on melt fractions. Wider adoption of these new methods and advances in data collection are needed to enable a revolution in imaging magma reservoirs.},
	issn = {2296-6463},
	doi = {10.3389/feart.2022.970131},
	url = {https://www.frontiersin.org/articles/10.3389/feart.2022.970131},
	author = {Paulatto, Michele and Hooft, Emilie E. E. and Chrapkiewicz, Kajetan and Heath, Benjamin and Toomey, Douglas R. and Morgan, Joanna V.}
}
@article {Bodmer2018,
	title = {Buoyant Asthenosphere Beneath Cascadia Influences Megathrust Segmentation},
	journal = {Geophysical Research Letters},
	volume = {45},
	number = {14},
	year = {2018},
	month = {jul},
	pages = {6954{\textendash}6962},
	issn = {0094-8276},
	doi = {10.1029/2018GL078700},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2018GL078700},
	author = {Bodmer, Miles and Toomey, Douglas R. and Hooft, Emilie E. E. and Schmandt, Brandon}
}
@article {Kim2018a,
	title = {Upper crustal Vp / Vs ratios at the Endeavour segment, Juan de Fuca Ridge, from joint inversion of P and S travel times: Implications for hydrothermal circulation},
	journal = {Geochemistry, Geophysics, Geosystems},
	year = {2018},
	month = {dec},
	pages = {2018GC007921},
	issn = {1525-2027},
	doi = {10.1029/2018GC007921},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2018GC007921},
	author = {Kim, Eunyoung and Toomey, Douglas R. and Hooft, Emilie E. E. and Wilcock, William S. D. and Weekly, Robert T. and Lee, Sang-Mook and Kim, Young Hee}
}
@article {Kim2018,
	title = {Upper crustal Vp / Vs ratios at the Endeavour segment, Juan de Fuca Ridge, from joint inversion of P and S travel times: Implications for hydrothermal circulation},
	journal = {Geochemistry, Geophysics, Geosystems},
	year = {2018},
	month = {dec},
	pages = {2018GC007921},
	issn = {1525-2027},
	doi = {10.1029/2018GC007921},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2018GC007921},
	author = {Kim, Eunyoung and Toomey, Douglas R. and Hooft, Emilie E. E. and Wilcock, William S. D. and Weekly, Robert T. and Lee, Sang-Mook and Kim, Young Hee}
}
@article {Byrnes2017a,
	title = {Mantle dynamics beneath the discrete and diffuse plate boundaries of the Juan de Fuca plate: Results from Casascadia Initiative body wave tomography},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {18},
	number = {8},
	year = {2017},
	month = {aug},
	pages = {2906{\textendash}2929},
	issn = {1525-2027},
	doi = {10.1002/2017GC006980},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/2017GC006980},
	author = {Byrnes, Joseph S. and Toomey, Douglas R. and Hooft, Emilie E. E. and N{\'a}b{\v e}lek, John and Braunmiller, Jochen}
}
@article {Arnoux2017,
	title = {Seismic evidence that black smoker heat flux is influenced by localized magma replenishment and associated increases in crustal permeability},
	journal = {Geophysical Research Letters},
	volume = {44},
	number = {4},
	year = {2017},
	month = {feb},
	pages = {1687{\textendash}1695},
	issn = {00948276},
	doi = {10.1002/2016GL071990},
	url = {http://doi.wiley.com/10.1002/2016GL071990},
	author = {Arnoux, Gillean M. and Toomey, Douglas R. and Hooft, Emilie E. E. and Wilcock, William S. D. and Morgan, Joanna and Warner, Mike and VanderBeek, Brandon P.}
}
@article {Soule2016,
	title = {Near-axis crustal structure and thickness of the Endeavour Segment, Juan de Fuca Ridge},
	journal = {Geophysical Research Letters},
	volume = {43},
	number = {11},
	year = {2016},
	month = {jun},
	pages = {5688{\textendash}5695},
	issn = {00948276},
	doi = {10.1002/2016GL068182},
	url = {http://doi.wiley.com/10.1002/2016GL068182},
	author = {Soule, Dax and Wilcock, William S. D. and Toomey, Douglas R. and Hooft, Emilie E. E. and Weekly, Robert T.}
}
@article {VanderBeek2016,
	title = {Segmentation of mid-ocean ridges attributed to oblique mantle divergence},
	journal = {Nature Geoscience},
	volume = {9},
	number = {8},
	year = {2016},
	month = {aug},
	pages = {636{\textendash}642},
	issn = {1752-0894},
	doi = {10.1038/ngeo2745},
	url = {http://www.nature.com/articles/ngeo2745},
	author = {VanderBeek, Brandon P. and Toomey, Douglas R. and Hooft, Emilie E. E. and Wilcock, William S. D.}
}
