@article {lee_detection_2022,
	title = {Detection of Magma Beneath the Northern and Southern Rift Zones of Axial Seamount at the Juan de Fuca Ridge},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {23},
	number = {8},
	year = {2022},
	note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1029/2022GC010426},
	pages = {e2022GC010426},
	abstract = {Axial Seamount is an active hotspot-related volcanic system located along the Juan de Fuca Ridge (JdFR) that includes a central volcano and bounding northern and southern rift zones (NRZ and SRZ). Three documented volcanic eruptions in 1998, 2011, and 2015 included dike propagation into and eruptions within the rift zones that are believed to have been sourced from the well-imaged large magma reservoir found beneath the central volcano. However, areas beyond the central volcano have not been explored for potential magma sources that could have contributed to these events, and geochemical studies of older rift zone lavas indicate differences in compositions suggestive of magma reservoirs fed by more mid-ocean ridge-dominated mantle sources. In this study, we analyze multichannel seismic data acquired in 2002 to characterize the internal crustal structure of the rift zones. The new reflectivity images reveal small (<5 km wide) and discontinuous crustal magma bodies at depths of \~{}1.5 to 4 km beneath and in the vicinity of the rift zone lava flows from the three eruptions. We also image wide magma bodies within the overlap regions between the rift zones and neighboring segments of JdFR including a 6.4 km wide body under the east flank of NRZ and a 1-km wide, \~{}400 to 500 m, thick body near the base of the crust under the SRZ-Vance overlap basin. Collectively the new observations indicate that multiple small crustal magma bodies underlie Axial segment, in addition to the main reservoir, and likely contribute to rift zone magmatism with implications for interpretations of seismicity patterns and lava flow compositions.},
	issn = {1525-2027},
	doi = {10.1029/2022GC010426},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2022GC010426},
	author = {Lee, Michelle K. and Carbotte, Suzanne M. and Arnulf, Adrien F.}
}
@article {RN122,
	title = {A Joint Inversion for Three-dimensional P and S Wave Velocity Structure and Earthquake Locations Beneath Axial Seamount},
	journal = {Journal of Geophysical Research: Solid Earth},
	volume = {n/a},
	number = {n/a},
	year = {2019},
	type = {Journal Article},
	abstract = {Axial Seamount is a prominent volcano located at the intersection of the Juan de Fuca Ridge and the Cobb-Eickelberg hot spot in the northeast Pacific Ocean that has erupted in 1998, 2011, and 2015. The 2015 eruption was recorded by a seven-station seismic network in the southern part of the summit caldera that forms part of the Ocean Observatories Initiative Cabled Array. We utilize a data set of ~3,900 well-recorded earthquakes from January 2015 to February 2017 and a three-dimensional P wave velocity model obtained previously from active source data to conduct a joint inversion for three-dimensional P and S wave velocities and hypocentral parameters. The resulting velocity models are used to relocate >76,000 earthquakes with >=10 arrival times. The velocity models reveal a low-velocity anomaly in the center of the southern caldera at depths less than ~2 km, which corresponds to the top of the magma chamber and is interpreted as a region that is intensely fractured by the cyclical deformation of the caldera. High velocities around the caldera rim are likely due to consolidated undeformed lava flows. Low VP/VS in the southern caldera is consistent with the presence of hydrothermal vapor. Low S wave velocities and high VP/VS in the northern caldera may indicate a region dominated by thin cracks caused by dike injection. The relocated earthquakes delineate outward-dipping ring faults more clearly than previous studies and image a subvertical inward-dipping fault within the network that connects to the east caldera wall and eruptive fissures.},
	keywords = {axial seamount, Earthquakes location, Hydrothermal systems, Joint inversion, Tomography, volcano},
	issn = {2169-9313},
	doi = {10.1029/2019JB017970},
	author = {Baillard, Christian and Wilcock, William S. D. and Arnulf, Adrien F. and Tolstoy, Maya and Waldhauser, Felix}
}
