@article {macgregor_seismic_2023,
	title = {A Seismic Tomography, Gravity, and Flexure Study of the Crust and Upper Mantle Structure of the Hawaiian Ridge: 1},
	journal = {Journal of Geophysical Research: Solid Earth},
	volume = {128},
	number = {12},
	year = {2023},
	note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1029/2023JB027218},
	month = {11/2023},
	pages = {e2023JB027218},
	abstract = {The Hawaiian Ridge has long been a focus site for studying lithospheric flexure due to intraplate volcano loading, but crucial load and flexure details remain unclear. We address this problem using wide-angle seismic refraction and reflection data acquired along a \~{}535-km-long profile that intersects the ridge between the islands of Maui and Hawai{\textquoteright}i and crosses 80{\textendash}95 Myr-old lithosphere. A tomographic image constructed using travel time data of several seismic phases reveals broad flexure of Pacific oceanic crust extending up to \~{}200{\textendash}250 km either side of the Hawaiian Ridge, and vertically up to \~{}6{\textendash}7 km. The P-wave velocity structure, verified by gravity modeling, reveals that the west flank of Hawaii is comprised of extrusive lavas overlain by volcanoclastic sediments and a carbonate platform. In contrast, the H{\={a}}na Ridge, southeast of Maui, contains a high-velocity core consistent with mafic or ultramafic intrusive rocks. Magmatic underplating along the seismic line is not evident. Reflectors at the top and bottom of the pre-existing oceanic crust suggest a \~{}4.5{\textendash}6 km crustal thickness. Simple three-dimensional flexure modeling with an elastic plate thickness, Te, of 26.7 km shows that the depths to the reflectors beneath the western flank of Hawai{\textquoteright}i can be explained by volcano loading in which Maui and the older islands in the ridge contribute \~{}43\% to the flexure and the island of Hawai{\textquoteright}i \~{}51\%. Previous studies, however, revealed a higher Te beneath the eastern flank of Hawai{\textquoteright}i suggesting that isostatic compensation may not yet be complete at the youngest end of the ridge.},
	keywords = {Hawaiian ridge, lithospheric flexure, marine gravity, plate loading, seismic tomography, volcano structure},
	issn = {2169-9356},
	doi = {10.1029/2023JB027218},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2023JB027218},
	author = {MacGregor, B. G. and Dunn, R. A. and Watts, A. B. and Xu, C. and Shillington, D. J.}
}
@article {xu_seismic_2022,
	title = {A Seismic Tomography, Gravity, and Flexure Study of the Crust and Upper Mantle Structure of the Emperor Seamounts at Jimmu Guyot},
	journal = {Journal of Geophysical Research: Solid Earth},
	volume = {127},
	number = {6},
	year = {2022},
	note = {_eprint: https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2021JB023241},
	month = {05/2022},
	pages = {e2021JB023241},
	abstract = {The intraplate Hawaiian-Emperor Seamount Chain has long been considered a hotspot track generated by the motion of the Pacific plate over a deep mantle plume, and an ideal feature therefore for studies of volcanic structure, magma supply, plume-crust interaction, flexural loading, and upper mantle rheology. Despite their importance as a major component of the chain, the Emperor Seamounts have been relatively little studied. In this paper, we present the results of an active-source wide-angle reflection and refraction experiment conducted along an ocean-bottom-seismograph (OBS) line oriented perpendicular to the seamount chain, crossing Jimmu guyot. The tomographic P wave velocity model, using \~{}20,000 travel times from 26 OBSs, suggests that there is a high-velocity (>6.0 km/s) intrusive core within the edifice, and the extrusive-to-intrusive ratio is estimated to be \~{}2.5, indicating that Jimmu was built mainly by extrusive processes. The total volume for magmatic material above the top of the oceanic crust is \~{}5.3 {\texttimes} 104 km3, and the related volume flux is \~{}0.96 m3/s during the formation of Jimmu. Under volcanic loading, the \~{}5.3-km-thick oceanic crust is depressed by \~{}3.8 km over a broad region. Using the standard relationships between Vp and density, the velocity model is verified by gravity modeling, and plate flexure modeling indicates an effective elastic thickness (Te) of \~{}14 km. Finally, we find no evidence for large-scale magmatic underplating beneath the pre-existing crust.},
	keywords = {Emperor Seamounts, gravity modeling, oceanic crust, plate flexure, seamount structure, seismic tomography},
	issn = {2169-9356},
	doi = {10.1029/2021JB023241},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2021JB023241},
	author = {Xu, C. and Dunn, R. A. and Watts, A. B. and Shillington, D. J. and Grevemeyer, I. and G{\'o}mez de la Pe{\~n}a, L. and Boston, B. B.}
}
