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  • 1
    Publication Date: 2022-05-25
    Description: © The Author(s), 2015. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Journal of Geophysical Research: Oceans 120 (2015): 5932–5944, doi:10.1002/2015JC010914.
    Description: The observed changes in physical properties of sea ice such as decreased thickness and increased melt pond cover severely impact the energy budget of Arctic sea ice. Increased light transmission leads to increased deposition of solar energy in the upper ocean and thus plays a crucial role for amount and timing of sea-ice-melt and under-ice primary production. Recent developments in underwater technology provide new opportunities to study light transmission below the largely inaccessible underside of sea ice. We measured spectral under-ice radiance and irradiance using the new Nereid Under-Ice (NUI) underwater robotic vehicle, during a cruise of the R/V Polarstern to 83°N 6°W in the Arctic Ocean in July 2014. NUI is a next generation hybrid remotely operated vehicle (H-ROV) designed for both remotely piloted and autonomous surveys underneath land-fast and moving sea ice. Here we present results from one of the first comprehensive scientific dives of NUI employing its interdisciplinary sensor suite. We combine under-ice optical measurements with three dimensional under-ice topography (multibeam sonar) and aerial images of the surface conditions. We investigate the influence of spatially varying ice-thickness and surface properties on the spatial variability of light transmittance during summer. Our results show that surface properties such as melt ponds dominate the spatial distribution of the under-ice light field on small scales (〈1000 m2), while sea ice-thickness is the most important predictor for light transmission on larger scales. In addition, we propose the use of an algorithm to obtain histograms of light transmission from distributions of sea ice thickness and surface albedo.
    Description: U.S. National Science Foundation Office of Polar Programs NSF OPP ANT-1126311, National Oceanic and Atmospheric Administration Office of Exploration and Research NOAA OER NA14OAR4320158, European Research Council Advanced Investigator Grant Number: 294757
    Keywords: Melt ponds ; Light transmittance ; Albedo ; ROV ; Spatial variability ; Shortwave radiation
    Repository Name: Woods Hole Open Access Server
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  • 2
    Publication Date: 2022-05-25
    Description: Author Posting. © American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 14 (2013): 317–327, doi:10.1002/ggge.20063.
    Description: Deep-sea ultramafic-hosted vent systems have the potential to provide large amounts of metabolic energy to both autotrophic and heterotrophic microorganisms in their dispersing hydrothermal plumes. Such vent-systems release large quantities of hydrogen and methane to the water column, both of which can be exploited by autotrophic microorganisms. Carbon cycling in these hydrothermal plumes may, therefore, have an important influence on open-ocean biogeochemistry. In this study, we investigated an ultramafic-hosted system on the Mid-Cayman Rise, emitting metal-poor and hydrogen sulfide-, methane-, and hydrogen-rich hydrothermal fluids. Total organic carbon concentrations in the plume ranged between 42.1 and 51.1 μM (background = 43.2 ± 0.7 μM (n = 5)) and near-field plume samples with elevated methane concentrations imply the presence of chemoautotrophic primary production and in particular methanotrophy. In parts of the plume characterized by persistent potential temperature anomalies but lacking elevated methane concentrations, we found elevated organic carbon concentrations of up to 51.1 μM, most likely resulting from the presence of heterotrophic communities, their extracellular products and vent larvae. Elevated carbon concentrations up to 47.4 μM were detected even in far-field plume samples. Within the Von Damm hydrothermal plume, we have used our data to hypothesize a microbial food web in which chemoautotrophy supports a heterotrophic community of microorganisms. Such an active microbial food web would provide a source of labile organic carbon to the deep ocean that should be considered in any future studies evaluating sources and sinks of carbon from hydrothermal venting to the deep ocean.
    Description: The research reported in this paper was supported by ship time and support provided by NOAA’s Office of Ocean Exploration and Research and the Office of Marine and Aviation Operations and NSF’s Division of Ocean Sciences (Grant OCE-1061863) and by further shore-based research from both the National Science Foundation (NSF OCE-1061863) and NASA’s ASTEP Program (Grant # NNX09AB75G). The contributions of SB and MC were carried out at the Jet Propulsion Laboratory (JPL), California Institute of Technology, under contract with the National Aeronautics and Space Administration (NASA), with support from the NASA ASTEP Program.
    Description: 2013-08-22
    Keywords: Hydrothermal ; Food web ; Microorganisms ; Plume ; Carbon ; Ultramafic
    Repository Name: Woods Hole Open Access Server
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  • 3
    Publication Date: 2022-05-25
    Description: Author Posting. © American Geophysical Union, 2013. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 14 (2013): 4892–4905, doi:10.1002/2013GC004998.
    Description: The InterRidge Vents Database is available online as the authoritative reference for locations of active submarine hydrothermal vent fields. Here we describe the revision of the database to an open source content management system and conduct a meta-analysis of the global distribution of known active vent fields. The number of known active vent fields has almost doubled in the past decade (521 as of year 2009), with about half visually confirmed and others inferred active from physical and chemical clues. Although previously known mainly from mid-ocean ridges (MORs), active vent fields at MORs now comprise only half of the total known, with about a quarter each now known at volcanic arcs and back-arc spreading centers. Discoveries in arc and back-arc settings resulted in an increase in known vent fields within exclusive economic zones, consequently reducing the proportion known in high seas to one third. The increase in known vent fields reflects a number of factors, including increased national and commercial interests in seafloor hydrothermal deposits as mineral resources. The purpose of the database now extends beyond academic research and education and into marine policy and management, with at least 18% of known vent fields in areas granted or pending applications for mineral prospecting and 8% in marine protected areas.
    Description: For support to prepare this manuscript, we thank the National Science Foundation (OCE08-38923, GeoEd12-02977), the NOAA Vents (now Earth-Ocean Interactions) Program and the Joint Institute for the Study of the Atmosphere and Ocean (JISAO) under NOAA Cooperative Agreement NA10OAR4320148, and WHOI.
    Description: 2014-05-19
    Keywords: Hydrothermal vent ; Deep-sea vent ; Hydrothermal activity ; Drupal
    Repository Name: Woods Hole Open Access Server
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  • 4
    Publication Date: 2022-05-25
    Description: Author Posting. © American Geophysical Union, 2015. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 16 (2015): 2762–2774, doi:10.1002/2015GC005831.
    Description: Processes active in rising hydrothermal plumes, such as precipitation, particle aggregation, and biological growth, affect particle size distributions and can exert important influences on the biogeochemical impact of submarine venting of iron to the oceans and their sediments. However, observations to date of particle size distribution within these systems are both limited and conflicting. In a novel buoyant hydrothermal plume study at the recently discovered high-temperature (398°C) Piccard Hydrothermal Field, Mid-Cayman Rise, we report optical measurements of particle size distributions (PSDs). We describe the plume PSD in terms of a simple, power-law model commonly used in studies of upper and coastal ocean particle dynamics. Observed PSD slopes, derived from spectral beam attenuation and laser diffraction measurements, are among the highest found to date anywhere in the ocean and ranged from 2.9 to 8.5. Beam attenuation at 650 nm ranged from near zero to a rarely observed maximum of 192 m−1 at 3.5 m above the vent. We did not find large (〉100 μm) particles that would settle rapidly to the sediments. Instead, beam attenuation was well-correlated to total iron, suggesting the first-order importance of particle dilution, rather than precipitation or dissolution, in the rising plume at Piccard. Our observations at Piccard caution against the assumption of rapid deposition of hydrothermal, particulate metal fluxes, and illustrate the need for more particle size and composition measurements across a broader range of sites, globally.
    Description: This work was funded by the National Science Foundation (OCE-1029223; OCE-1061863), NASA (NNX09AB75G) and Woods Hole Oceanographic Institution's Deep Ocean Exploration Institute and Ocean Ridge Initiative. Ship time (R/V Falkor cruise FK008) was funded by the Schmidt Ocean Institute and M.L.E. was supported by a WHOI Postdoctoral Scholar fellowship.
    Description: 2016-02-25
    Keywords: Hydrothermal particulate iron fluxes ; Particle size distribution ; Particle inherent optical properties ; In situ optical sensors ; Mid-Cayman Rise ; Piccard Hydrothermal Field
    Repository Name: Woods Hole Open Access Server
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  • 5
    Publication Date: 2022-10-26
    Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Howell, K. L., Hilario, A., Allcock, A. L., Bailey, D. M., Baker, M., Clark, M. R., Colaco, A., Copley, J., Cordes, E. E., Danovaro, R., Dissanayake, A., Escobar, E., Esquete, P., Gallagher, A. J., Gates, A. R., Gaudron, S. M., German, C. R., Gjerde, K. M., Higgs, N. D., Le Bris, N., Levin, L. A., Manea, E., McClain, C., Menot, L., Mestre, N. C., Metaxas, A., Milligan, R. J., Muthumbi, A. W. N., Narayanaswamy, B. E., Ramalho, S. P., Ramirez-Llodra, E., Robson, L. M., Rogers, A. D., Sellanes, J., Sigwart, J. D., Sink, K., Snelgrove, P. V. R., Stefanoudis, P., V., Sumida, P. Y., Taylor, M. L., Thurber, A. R., Vieira, R. P., Watanabe, H. K., Woodall, L. C., & Xavier, J. R. A blueprint for an inclusive, global deep-sea ocean decade field program. Frontiers in Marine Science, 7, (2020): 584861, doi:10.3389/fmars.2020.584861.
    Description: The ocean plays a crucial role in the functioning of the Earth System and in the provision of vital goods and services. The United Nations (UN) declared 2021–2030 as the UN Decade of Ocean Science for Sustainable Development. The Roadmap for the Ocean Decade aims to achieve six critical societal outcomes (SOs) by 2030, through the pursuit of four objectives (Os). It specifically recognizes the scarcity of biological data for deep-sea biomes, and challenges the global scientific community to conduct research to advance understanding of deep-sea ecosystems to inform sustainable management. In this paper, we map four key scientific questions identified by the academic community to the Ocean Decade SOs: (i) What is the diversity of life in the deep ocean? (ii) How are populations and habitats connected? (iii) What is the role of living organisms in ecosystem function and service provision? and (iv) How do species, communities, and ecosystems respond to disturbance? We then consider the design of a global-scale program to address these questions by reviewing key drivers of ecological pattern and process. We recommend using the following criteria to stratify a global survey design: biogeographic region, depth, horizontal distance, substrate type, high and low climate hazard, fished/unfished, near/far from sources of pollution, licensed/protected from industry activities. We consider both spatial and temporal surveys, and emphasize new biological data collection that prioritizes southern and polar latitudes, deeper (〉 2000 m) depths, and midwater environments. We provide guidance on observational, experimental, and monitoring needs for different benthic and pelagic ecosystems. We then review recent efforts to standardize biological data and specimen collection and archiving, making “sampling design to knowledge application” recommendations in the context of a new global program. We also review and comment on needs, and recommend actions, to develop capacity in deep-sea research; and the role of inclusivity - from accessing indigenous and local knowledge to the sharing of technologies - as part of such a global program. We discuss the concept of a new global deep-sea biological research program ‘Challenger 150,’ highlighting what it could deliver for the Ocean Decade and UN Sustainable Development Goal 14.
    Description: Development of this paper was supported by funding from the Scientific Committee on Oceanic Research (SCOR) awarded to KH and AH as working group 159 co-chairs. KH, BN, and KS are supported by the UKRI funded One Ocean Hub NE/S008950/1. AH work is supported by the CESAM (UIDP/50017/2020 + 1432 UIDB/50017/2020) that is funded by Fundação para a Ciência e a Tecnologia (FCT)/MCTES through national funds. AA is supported by Science Foundation Ireland and the Marine Institute under the Investigators Program Grant Number SFI/15/IA/3100 co-funded under the European Regional Development Fund 2014–2020. AC is supported through the FunAzores -ACORES 01-0145-FEDER-000123 grant and by FCT through strategic project UID/05634/2020 and FCT and Direção-Geral de Politica do Mar (DGPM) through the project Mining2/2017/005. PE is funded by national funds (OE), through FCT in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. SG research is supported by CNRS funds. CG is supported by an Independent Study Award and the Investment in Science Fund at WHOI. KG gratefully acknowledges support from Synchronicity Earth. LL is funded by the NOAA Office of Ocean Exploration and Research (NA19OAR0110305) and the US National Science Foundation (OCE 1634172). NM is supported by FCT and DGPM, through the project Mining2/2017/001 and the FCT grants CEECIND/00526/2017, UIDB/00350/2020 + UIDP/00350/2020. SR is funded by the FCTgrant CEECIND/00758/2017. JS is supported by ANID FONDECYT #1181153 and ANID Millennium Science Initiative Program #NC120030. JX research is funded by the European Union’s Horizon 2020 research and innovation program through the SponGES project (grant agreement no. 679849) and further supported by national funds through FCT within the scope of UIDB/04423/2020 and UIDP/04423/2020. The Natural Sciences and Engineering Council of Canada supports AM and PVRS. MB and the Deep-Ocean Stewardship Initiative are supported by Arcadia - A charitable fund of Lisbet Rausing and Peter Baldwin. BN work is supported by the NERC funded Arctic PRIZE NE/P006302/1.
    Keywords: Deep sea ; Blue economy ; Ocean Decade ; Biodivercity ; Essential ocean variables
    Repository Name: Woods Hole Open Access Server
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  • 6
    Publication Date: 2022-10-26
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Woods, D., Cheadle, M., John, B., German, C., & Van Dover, C. Making use of relicts: brisingid seastars aggregate on hydrothermally inactive sulfide chimneys near black smokers. Frontiers in Marine Science, 9, (2022): 774628, https://doi.org/10.3389/fmars.2022.774628.
    Description: When hydrothermal activity ceases at black-smoker chimneys on mid-ocean ridges, populations of associated invertebrates hosting chemoautotrophic endosymbionts decline and then disappear, but the chimneys can persist on the seabed as relicts. Suspension-feeding brisingid seastars colonize hydrothermally inactive (relict) chimneys on the East Pacific Rise (EPR), though their distribution relative to available hard substrata and proximity to hydrothermal activity is poorly documented. In this study, brisingid abundance on sulfide and basalt substrata was assessed along an ∼3,700 m ROV Jason II transect at the summit of Pito Seamount (SE Pacific; ∼2,275 m). Brisingids were non-randomly distributed, with highest densities (up to ∼300 m–2) on relict sulfides chimneys near active black smokers. Brisingids were relatively uncommon on basalt substrata, and absent on black smokers. We infer that both relict sulfide structures and proximity to black smokers play key roles in the maintenance of dense brisingid populations on Pito Seamount and in similar environments on the EPR. Our observations suggest that experimental introduction of “artificial” relict chimneys providing microtopographic relief could test whether such an approach might mitigate potential impacts of mineral extraction on populations of suspension-feeding invertebrates.
    Description: his project was partially supported by the Global Ocean Biodiversity Initiative through the International Climate Initiative (IKI; grant no. 16_IV_049_Global_A_Global Ocean Biodiversity Initiative GOBI). The Federal Ministry for the Environment, Nature Conservation, and Nuclear Safety (BMU) supports IKI on the basis of a decision adopted by the German Bundestag. DW was supported by Duke University funds to CV. CG’s participation was funded through WHOI’s Deep Ocean Exploration Institute. The AT37-08 cruise was funded by NSF OCE-1459462 (MC and BJ) and OCE-1459387 (J Gee, Scripps Institution of Oceanography).
    Keywords: Brisingid seastar ; East Pacific Rise (EPR) ; Hydrothermal vent ; Pito Seamount ; Nautile Hydrothermal Field ; Deep-sea mining (DSM) ; Black smoker ; Hydrothermally inactive sulfide
    Repository Name: Woods Hole Open Access Server
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  • 7
    Publication Date: 2022-05-27
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Cohen, N. R., Noble, A. E., Moran, D. M., McIlvin, M. R., Goepfert, T. J., Hawco, N. J., German, C. R., Horner, T. J., Lamborg, C. H., McCrow, J. P., Allen, A. E., & Saito, M. A. Hydrothermal trace metal release and microbial metabolism in the northeastern Lau Basin of the South Pacific Ocean. Biogeosciences, 18(19), (2021): 5397–5422, https://doi.org/10.5194/bg-18-5397-2021.
    Description: Bioactive trace metals are critical micronutrients for marine microorganisms due to their role in mediating biological redox reactions, and complex biogeochemical processes control their distributions. Hydrothermal vents may represent an important source of metals to microorganisms, especially those inhabiting low-iron waters, such as in the southwest Pacific Ocean. Previous measurements of primordial 3He indicate a significant hydrothermal source originating in the northeastern (NE) Lau Basin, with the plume advecting into the southwest Pacific Ocean at 1500–2000 m depth (Lupton et al., 2004). Studies investigating the long-range transport of trace metals associated with such dispersing plumes are rare, and the biogeochemical impacts on local microbial physiology have not yet been described. Here we quantified dissolved metals and assessed microbial metaproteomes across a transect spanning the tropical and equatorial Pacific with a focus on the hydrothermally active NE Lau Basin and report elevated iron and manganese concentrations across 441 km of the southwest Pacific. The most intense signal was detected near the Mangatolo Triple Junction (MTJ) and Northeast Lau Spreading Center (NELSC), in close proximity to the previously reported 3He signature. Protein content in distal-plume-influenced seawater, which was high in metals, was overall similar to background locations, though key prokaryotic proteins involved in metal and organic uptake, protein degradation, and chemoautotrophy were abundant compared to deep waters outside of the distal plume. Our results demonstrate that trace metals derived from the NE Lau Basin are transported over appreciable distances into the southwest Pacific Ocean and that bioactive chemical resources released from submarine vent systems are utilized by surrounding deep-sea microbes, influencing both their physiology and their contributions to ocean biogeochemical cycling.
    Description: This research has been supported by the National Science Foundation (grant nos. 1031271, 1924554, 1850719, 1736599, and 1851007); the Gordon and Betty Moore Foundation (grant no. 3782); and the Simons Foundation (grant no. 544236).
    Repository Name: Woods Hole Open Access Server
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  • 8
    Publication Date: 2022-05-26
    Description: © The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Environmental Microbiology 18 (2016): 1970–1987, doi:10.1111/1462-2920.13173.
    Description: Warm fluids emanating from hydrothermal vents can be used as windows into the rocky subseafloor habitat and its resident microbial community. Two new vent systems on the Mid-Cayman Rise each exhibits novel geologic settings and distinctively hydrogen-rich vent fluid compositions. We have determined and compared the chemistry, potential energy yielding reactions, abundance, community composition, diversity, and function of microbes in venting fluids from both sites: Piccard, the world's deepest vent site, hosted in mafic rocks; and Von Damm, an adjacent, ultramafic-influenced system. Von Damm hosted a wider diversity of lineages and metabolisms in comparison to Piccard, consistent with thermodynamic models that predict more numerous energy sources at ultramafic systems. There was little overlap in the phylotypes found at each site, although similar and dominant hydrogen-utilizing genera were present at both. Despite the differences in community structure, depth, geology, and fluid chemistry, energetic modelling and metagenomic analysis indicate near functional equivalence between Von Damm and Piccard, likely driven by the high hydrogen concentrations and elevated temperatures at both sites. Results are compared with hydrothermal sites worldwide to provide a global perspective on the distinctiveness of these newly discovered sites and the interplay among rocks, fluid composition and life in the subseafloor.
    Description: National Aeronautics and Space Administration Grant Number: NNX09AB756; Alfred P. Sloan Foundation; NSF Grant Number: OCE106183
    Repository Name: Woods Hole Open Access Server
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  • 9
    Publication Date: 2022-05-26
    Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Wagner, J. K. S., Smart, C., & German, C. R. Discovery and mapping of the Triton seep site, Redondo Knoll: fluid flow and microbial colonization within an oxygen minimum zone. Frontiers in Marine Science, 7, (2020): 108, doi:10.3389/fmars.2020.00108.
    Description: This paper examines a deep-water (∼900 m) cold-seep discovered in a low oxygen environment ∼30 km off the California coast in 2015 during an E/V Nautilus telepresence-enabled cruise. This Triton site was initially detected from bubble flares identified via shipboard multibeam sonar and was then confirmed visually using the remotely operated vehicle (ROV) Hercules. High resolution mapping (to 1 cm resolution) and co-registered imaging has provided us with a comprehensive site overview – both of the geologic setting and the extent of the associated microbial colonization. The Triton site represents an active cold-seep where microorganisms can act as primary producers at the base of a chemosynthesis-driven food chain. But it is also located near the core of a local oxygen minimum zone (OMZ), averaging 〈0.75 μM oxygen, which is significantly below average ocean levels (180–270 μM) and, indeed, extreme even among OMZs as a whole which are defined to occur at all oxygen concentrations 〈22 μM. Extensive microbial mats, extending for 〉100 m across the seafloor, dominate the site, while typical seep-endemic macro-fauna were noticeably absent from our co-registered photographic and high-resolution mapping surveys – especially when compared to all adjacent seep sites within the same California Borderlands region. While such absences of abundant macro-fauna could be attributable to variations in the availability of dissolved oxygen in the overlying water column this need not necessarily be the case. An alternate possibility is that the zonation in microbial activity that is readily observable at the seafloor at Triton reflects, instead, a concentric pattern of radially diminishing fluxes of reductants from the underlying seafloor. This unusual but readily accessible discovery, in close proximity to Los Angeles harbor, provides an intriguing new natural laboratory at which to examine biogeochemical and microbiological interactions associated with the functioning of cold seep ecosystems within an OMZ.
    Description: Ship time was funded by NOAA – Office of Exploration and Research and the Ocean Exploration Trust. This material is based upon work supported by a National Science Foundation Graduate Research Fellowship (to JW), the Office of Naval Research (to CS), and NASA’s Astrobiology program (to CG).
    Keywords: cold seep ; oxygen minimum zone ; California Borderlands ; microbial mats ; continental margin
    Repository Name: Woods Hole Open Access Server
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  • 10
    Publication Date: 2022-05-26
    Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in German, C. R., Resing, J. A., Xu, G., Yeo, I. A., Walker, S. L., Devey, C. W., Moffett, J. W., Cutter, G. A., Hyvernaud, O., & Reymond, D. Hydrothermal activity and seismicity at teahitia seamount: Reactivation of the society islands hotspot? Frontiers in Marine Science, 7, (2020): 73, doi:10.3389/fmars.2020.00073.
    Description: Along mid-ocean ridges, submarine venting has been found at all spreading rates and in every ocean basin. By contrast, intraplate hydrothermal activity has only been reported from five locations, worldwide. Here we extend the time series at one of those sites, Teahitia Seamount, which was first shown to be hydrothermally active in 1983 but had not been revisited since 1999. Previously, submersible investigations had led to the discovery of low-temperature (≤30°C) venting associated with the summit of Teahitia Seamount at ≤1500 m. In December 2013 we returned to the same site at the culmination of the US GEOTRACES Eastern South Tropical Pacific (GP16) transect and found evidence for ongoing venting in the form of a non-buoyant hydrothermal plume at a depth of 1400 m. Multi-beam mapping revealed the same composite volcano morphology described previously for Teahitia including four prominent cones. The plume overlying the summit showed distinct in situ optical backscatter and redox anomalies, coupled with high concentrations of total dissolvable Fe (≤186 nmol/L) and Mn (≤33 nmol/L) that are all diagnostic of venting at the underlying seafloor. Continuous seismic records from 1986-present reveal a ∼15 year period of quiescence at Teahitia, following the seismic crisis that first stimulated its submersible-led investigation. Since 2007, however, the frequency of seismicity at Teahitia, coupled with the low magnitude of those events, are suggestive of magmatic reactivation. Separately, distinct seismicity at the adjacent Rocard seamount has also been attributed to submarine extrusive volcanism in 2011 and in 2013. Theoretical modeling of the hydrothermal plume signals detected suggest a minimum heat flux of 10 MW at the summit of Teahitia. Those model simulations can only be sourced from an area of low-temperature venting such as that originally reported from Teahitia if the temperature of the fluids exiting the seabed has increased significantly, from ≤30°C to ∼70°C. These model seafloor temperatures and our direct plume observations are both consistent with reports from Loihi Seamount, Hawaii, ∼10 year following an episode of seafloor volcanism. We hypothesize that the Society Islands hotspot may be undergoing a similar episode of both magmatic and hydrothermal reactivation.
    Description: Field work for this project was funded through NSF Awards to CG (OCE-1130870), JR (OCE-1237011), GC (OCE-1130245), and JM (OCE-1131731). Post-cruise, additional support was provided through NOAA Cooperative Agreement NA15OAR432006 and funding from WHOI and GEOMAR Helmholtz Centre for Ocean Research Kiel. The Réseau Sismique Polynésie was supported at LDG by the Commissariat à l’Energie Atomique et aux Energies Renouvelables. Open Access publication charges for this paper were provided by the Schmidt Ocean Institute.
    Keywords: hydrothermal ; seamount ; hotspot ; Teahitia ; Tahiti ; Pacific
    Repository Name: Woods Hole Open Access Server
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