@article {philip_fluid_2023,
	title = {Fluid sources and overpressures within the central Cascadia Subduction Zone revealed by a warm, high-flux seafloor seep},
	journal = {Science Advances},
	volume = {9},
	number = {4},
	year = {2023},
	note = {Publisher: American Association for the Advancement of Science},
	pages = {eadd6688},
	abstract = {Pythia{\textquoteright}s Oasis is a newly discovered seafloor seep on the Central Oregon segment of the Cascadia Subduction Zone, where focused venting emits highly altered fluids ~9{\textdegree}C above the background temperature. The seep fluid chemistry is unique for Cascadia and includes extreme enrichment of boron and lithium and depletion of chloride, potassium, and magnesium. We conclude that the fluids are sourced from pore water compaction and mineral dehydration reactions with minimum source temperatures of 150{\textdegree} to 250{\textdegree}C, placing the source at or near the plate boundary offshore Central Oregon. Estimated fluid flow rates of 10 to 30 cm s-1 are orders of magnitude higher than those estimated elsewhere along the margin and are likely driven by extreme overpressures along the plate boundary. Probable draining of the overpressured reservoir along the vertical Alvin Canyon Fault indicates the important role that such faults may play in the regulation of pore fluid pressure throughout the forearc in Central Cascadia.},
	keywords = {3706 Geophysics},
	doi = {10.1126/sciadv.add6688},
	url = {https://www.science.org/doi/10.1126/sciadv.add6688},
	author = {Philip, Brendan T. and Solomon, Evan A. and Kelley, Deborah S. and Tr{\'e}hu, Anne M. and Whorley, Theresa L. and Roland, Emily and Tominaga, Masako and Collier, Robert W.}
}
@article {fruh-green_diversity_2022,
	title = {Diversity of magmatism, hydrothermal processes and microbial interactions at mid-ocean ridges},
	journal = {Nature Reviews Earth \& Environment},
	year = {2022},
	note = {Publisher: Nature Publishing Group},
	month = {nov},
	pages = {1{\textendash}20},
	abstract = {Hydrothermal circulation and alteration at mid-ocean ridges and ridge flanks have a key role in regulating seawater chemistry and global chemical fluxes, and support diverse ecosystems in the absence of light. In this Review, we outline tectonic, magmatic and hydrothermal processes that govern crustal architecture, alteration and biogeochemical cycles along mid-ocean ridges with different spreading rates. In general, hydrothermal systems vary from those that are magmatic-dominated with low-pH fluids >300 {\textdegree}C to serpentinizing systems with alkaline fluids <120 {\textdegree}C. Typically, slow-spreading ridges (rates <40 mm yr-1) have greater variability in magmatism, lithology and vent chemistry, which are influenced by detachment faults that expose lower-crustal and serpentinized mantle rocks. Hydrothermal alteration is an important sink for magnesium, sodium, sulfate and bicarbonate, and a net source of volatiles, iron and other nutrients to the deep ocean and vent ecosystems. Magmatic hydrothermal systems sustain a vast, hot and diverse microbial biosphere that represents a deep organic carbon source to ocean carbon budgets. In contrast, high-pH serpentinizing hydrothermal systems harbour a more limited microbial community consisting primarily of methane-metabolizing archaea. Continued advances in monitoring and analytical capabilities coupled with developments in metagenomic technologies will guide future investigations and discoveries in hydrothermal systems.},
	keywords = {Element cycles, Geochemistry, Marine biology, Tectonics},
	issn = {2662-138X},
	doi = {10.1038/s43017-022-00364-y},
	url = {https://www.nature.com/articles/s43017-022-00364-y},
	author = {Fr{\"u}h-Green, Gretchen L. and Kelley, Deborah S. and Lilley, Marvin D. and Cannat, Mathilde and Chavagnac, Valerie and Baross, John A.}
}
@article {RN76,
	title = {Lessons Learned From the United States Ocean Observatories Initiative},
	journal = {Frontiers in Marine Science},
	volume = {5},
	year = {2019},
	pages = {494},
	type = {Journal Article},
	abstract = {The Ocean Observatories Initiative (OOI) is a United States National Science Foundation-funded major research facility that provides continuous observations of the ocean and seafloor from coastal and open ocean locations in the Atlantic and Pacific. Multiple cycles of OOI infrastructure deployment, recovery, and refurbishment have occurred since operations began in 2014. This heterogeneous ocean observing infrastructure with multidisciplinary sampling in important but challenging locations has provided new scientific and engineering insights into the operation of a sustained ocean observing system. This paper summarizes the challenges, successes, and failures experienced to date and shares recommendations on best practices that will be of benefit to the global ocean observing community.},
	keywords = {best practices, equipment testing, lessons learned, ocean observing, technology development},
	issn = {2296-7745},
	doi = {10.3389/fmars.2018.00494},
	url = {https://www.frontiersin.org/article/10.3389/fmars.2018.00494},
	author = {Smith, Leslie M. and Yarincik, Kristen and Vaccari, Liana and Kaplan, Maxwell B. and Barth, John A. and Cram, Geoffrey S. and Fram, Jonathan P. and Harrington, Michael and Kawka, Orest E. and Kelley, Deborah S. and Matthias, Paul and Newhall, Kristopher and Palanza, Matthew and Plueddemann, Albert J. and Vardaro, Michael F. and White, Sheri N. and Weller, Robert Andrew}
}
@article {RN227,
	title = {Time-series measurements of bubble plume variability and water column methane distribution above Southern Hydrate Ridge, Oregon},
	journal = {Geochemistry, Geophysics, Geosystems},
	volume = {17},
	number = {3},
	year = {2016},
	pages = {1182-1196},
	type = {Journal Article},
	abstract = {An estimated 500{\textendash}2500 gigatons of methane carbon is sequestered in gas hydrate at continental margins and some of these deposits are associated with overlying methane seeps. To constrain the impact that seeps have on methane concentrations in overlying ocean waters and to characterize the bubble plumes that transport methane vertically into the ocean, water samples and time-series acoustic images were collected above Southern Hydrate Ridge (SHR), a well-studied hydrate-bearing seep site \~{}90 km west of Newport, Oregon. These data were coregistered with robotic vehicle observations to determine the origin of the seeps, the plume rise heights above the seafloor, and the temporal variability in bubble emissions. Results show that the locations of seep activity and bubble release remained unchanged over the 3 year time-series investigation, however, the magnitude of gas release was highly variable on hourly time scales. Bubble plumes were detected to depths of 320{\textendash}620 m below sea level (mbsl), in several cases exceeding the upper limit of hydrate stability by \~{}190 m. For the first time, sustained gas release was imaged at the Pinnacle site and in-between the Pinnacle and the Summit area of venting, indicating that the subseafloor transport of fluid and gas is not restricted to the Summit at SHR, requiring a revision of fluid-flow models. Dissolved methane concentrations above background levels from 100 to 300 mbsl are consistent with long-term seep gas transport into the upper water column, which may lead to the build-up of seep-derived carbon in regional subsurface waters and to increases in associated biological activity.},
	issn = {1525-2027},
	doi = {https://doi.org/10.1002/2016GC006250},
	url = {https://doi.org/10.1002/2016GC006250},
	author = {Philip, Brendan T. and Denny, Alden R. and Solomon, Evan A. and Kelley, Deborah S.}
}
@article {RN229,
	title = {Establishing a new era of submarine volcanic observatories: Cabling Axial Seamount and the Endeavour Segment of the Juan de Fuca Ridge},
	journal = {Marine Geology},
	volume = {352},
	year = {2014},
	pages = {426-450},
	type = {Journal Article},
	abstract = {At least 70\% of the volcanism on Earth occurs along the 65,000 km network of mid-ocean ridge (MOR) spreading centers. Within these dynamic environments, the highest fluxes of heat, chemicals, and biological material from the lithosphere to the hydrosphere occur during volcanic eruptions. However, because underwater volcanoes are difficult and expensive to access, researchers are rarely, if ever, in the right place at the right time to characterize these events. Therefore, our knowledge is limited about the linkages among hydrothermal, chemical and biological processes during seafloor formation and crustal evolution. To make significant advancements in understanding the evolution of MOR environments, the United States and Canada have invested in the first plate-scale submarine cabled observatory linked through the global Internet. Spanning the Juan de Fuca tectonic plate, these two networks include > 1700 km of cable and 14 subsea terminals that provide 8{\textendash}10 kW power and 10 Gbs communications to hundreds of instruments on the seafloor and throughout the overlying water column {\textemdash} resulting in a 24/7/365 presence in the oceans. Data and imagery are available in real- to near-real time.
The initial experimental sites for monitoring volcanic processes include the MOR volcanoes called Axial Seamount and the Endeavour Segment that are located on the Juan de Fuca Ridge. Axial, a hot-spot influenced seamount, is the most robust volcano along the ridge rising nearly 1400 m above the surrounding seafloor and it has erupted twice in the last 15 years. In contrast, the Endeavour Segment is characterized by more subdued topography with a well defined axial rift and it hosts one of the most intensely venting hydrothermal systems known. A non-eruptive spreading event lasting 6 years was documented at Endeavour between 1999 and 2005. Hydrothermal venting intensity, chemistry, and temperature, as well as associated biological communities at both sites were significantly perturbed by the magmatic and intrusive events. This paper presents the similarities and differences between the Axial and Endeavour volcanic systems and identifies reasons why they are ideal candidates for comparative studies. The U.S. has made a 25-year commitment for sustained observations using the cabled infrastructure. The highly expandable nature of submarine optical networking will allow for the future addition of novel experiments that utilize ever evolving advancements in computer sciences, robotics, genomics and sensor miniaturization. Comprehensive modeling of the myriad processes involved will continue to assimilate and integrate growing databases yielding a new understanding of integrated processes that create the seafloor in the global ocean basins.

},
	keywords = {axial seamount, cabled observatories, Endeavour Segment, hydrothermal vents, Juan de Fuca ridge, submarine volcanoes},
	issn = {0025-3227},
	doi = {https://doi.org/10.1016/j.margeo.2014.03.010},
	url = {https://www.sciencedirect.com/science/article/pii/S0025322714000723},
	author = {Kelley, Deborah S. and Delaney, John R. and Juniper, S. Kim}
}
@article {RN230,
	title = {Sulfur oxidizers dominate carbon fixation at a biogeochemical hot spot in the dark ocean},
	journal = {The ISME Journal},
	volume = {7},
	number = {12},
	year = {2013},
	pages = {2349-2360},
	type = {Journal Article},
	abstract = {Bacteria and archaea in the dark ocean (>200 m) comprise 0.3-1.3 billion tons of actively cycled marine carbon. Many of these microorganisms have the genetic potential to fix inorganic carbon (autotrophs) or assimilate single-carbon compounds (methylotrophs). We identified the functions of autotrophic and methylotrophic microorganisms in a vent plume at Axial Seamount, where hydrothermal activity provides a biogeochemical hot spot for carbon fixation in the dark ocean. Free-living members of the SUP05/Arctic96BD-19 clade of marine gamma-proteobacterial sulfur oxidizers (GSOs) are distributed throughout the northeastern Pacific Ocean and dominated hydrothermal plume waters at Axial Seamount. Marine GSOs expressed proteins for sulfur oxidation (adenosine phosphosulfate reductase, sox (sulfur oxidizing system), dissimilatory sulfite reductase and ATP sulfurylase), carbon fixation (ribulose-1,5-bisphosphate carboxylase oxygenase (RuBisCO)), aerobic respiration (cytochrome c oxidase) and nitrogen regulation (PII). Methylotrophs and iron oxidizers were also active in plume waters and expressed key proteins for methane oxidation and inorganic carbon fixation (particulate methane monooxygenase/methanol dehydrogenase and RuBisCO, respectively). Proteomic data suggest that free-living sulfur oxidizers and methylotrophs are among the dominant primary producers in vent plume waters in the northeastern Pacific Ocean.

},
	issn = {1751-7370},
	doi = {10.1038/ismej.2013.113},
	url = {https://doi.org/10.1038/ismej.2013.113},
	author = {Mattes, Timothy E. and Nunn, Brook L. and Marshall, Katharine T. and Proskurowski, Giora and Kelley, Deborah S. and Kawka, Orest E. and Goodlett, David R. and Hansell, Dennis A. and Morris, Robert M.}
}
