GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Document type
Keywords
  • 1
    facet.materialart.
    Unknown
    PANGAEA
    In:  Supplement to: Lichtschlag, Anna; Cevatoglu, Melis; Connelly, Douglas P; James, Rachael H; Bull, Jonathan M (2018): Increased Fluid Flow Activity in Shallow Sediments at the 3 km Long Hugin Fracture in the Central North Sea. Geochemistry, Geophysics, Geosystems, 19(1), 2-20, https://doi.org/10.1002/2017GC007181
    Publication Date: 2023-02-24
    Description: The North Sea hosts a wide variety of seafloor seeps that may be important for transfer of chemical species, such as methane, from the Earth's interior to its exterior. Here we provide geochemical and geophysical evidence for fluid flow within shallow sediments at the recently discovered, 3 -km long Hugin Fracture in the Central North Sea. Although venting of gas bubbles was not observed, concentrations of dissolved methane were significantly elevated (up to six-times background values) in the water column at various locations above the fracture, and microbial mats that form in the presence of methane were observed at the seafloor. Seismic amplitude anomalies revealed a bright spot at a fault bend that may be the source of the water column methane. Sediment porewaters recovered in close proximity to the Hugin Fracture indicate the presence of fluids from two different shallow (〈500 m) sources: (i) a reduced fluid characterized by elevated methane concentrations and/or high levels of dissolved sulfide (up to 6 mmol L-1), and (ii) a low-chlorinity fluid (Cl ~305 mmol L-1) that has low levels of dissolved methane and/or sulfide. The area of the seafloor affected by the presence of methane-enriched fluids is similar to the footprint of seepage from other morphological features in the North Sea.
    Keywords: ECO2; Sub-seabed CO2 Storage: Impact on Marine Ecosystems
    Type: Dataset
    Format: application/zip, 25 datasets
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2023-02-24
    Keywords: AA; Alkalinity, total; Autoanalyzer; Carbon, inorganic, dissolved; Cast number; CTD/Rosette; CTD-RO; Date/Time of event; DEPTH, water; ECO2; Elevation of event; Event label; Gas chromatography; James Cook; JC077; JC077-CTD1; JC077-CTD10; JC077-CTD11; JC077-CTD12; JC077-CTD13; JC077-CTD14; JC077-CTD15; JC077-CTD16; JC077-CTD17; JC077-CTD18; JC077-CTD19; JC077-CTD2; JC077-CTD20; JC077-CTD21; JC077-CTD22; JC077-CTD23; JC077-CTD24; JC077-CTD25; JC077-CTD26; JC077-CTD27; JC077-CTD28; JC077-CTD29; JC077-CTD3; JC077-CTD30; JC077-CTD31; JC077-CTD32; JC077-CTD33; JC077-CTD34; JC077-CTD35; JC077-CTD36; JC077-CTD37; JC077-CTD38; JC077-CTD39; JC077-CTD4; JC077-CTD40; JC077-CTD41; JC077-CTD42; JC077-CTD43; JC077-CTD44; JC077-CTD45; JC077-CTD46; JC077-CTD47; JC077-CTD48; JC077-CTD49; JC077-CTD5; JC077-CTD50; JC077-CTD51; JC077-CTD52; JC077-CTD53; JC077-CTD54; JC077-CTD55; JC077-CTD56; JC077-CTD57; JC077-CTD58; JC077-CTD59; JC077-CTD6; JC077-CTD60; JC077-CTD61; JC077-CTD62; JC077-CTD63; JC077-CTD64; JC077-CTD7; JC077-CTD8; JC077-CTD9; Latitude of event; Longitude of event; Methane; Nitrate and Nitrite; Oxygen; Phosphate; Silicate; Sub-seabed CO2 Storage: Impact on Marine Ecosystems; Titration; Titration, Winkler
    Type: Dataset
    Format: text/tab-separated-values, 1874 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    facet.materialart.
    Unknown
    PANGAEA
    In:  Supplement to: Hawkes, Jeffrey A; Rossel, Pamela E; Stubbins, Aron; Butterfield, David A; Connelly, Douglas P; Achterberg, Eric Pieter; Koschinsky, Andrea; Chavagnac, Valerie; Hansen, Christian T; Bach, Wolfgang; Dittmar, Thorsten (2015): Efficient removal of recalcitrant deep-ocean dissolved organic matter during hydrothermal circulation. Nature Geoscience, 8(11), 856-860, https://doi.org/10.1038/ngeo2543
    Publication Date: 2024-02-17
    Description: Oceanic dissolved organic carbon (DOC) is an important carbon pool, similar in magnitude to atmospheric CO2, but the fate of its oldest forms is not well understood (Dittmar and Stubbins, 2014; Hansell, 2013, doi:10.1146/annurev-marine-120710-100757). Hot hydrothermal circulation may facilitate the degradation of otherwise un-reactive dissolved organic matter, playing an important role in the long-term global carbon cycle. The oldest, most recalcitrant forms of DOC, which make up most of oceanic DOC, can be recovered by solid-phase extraction. Here we present measurements of solid-phase extractable DOC from samples collected between 2009 and 2013 at seven vent sites in the Atlantic, Pacific and Southern oceans, along with magnesium concentrations, a conservative tracer of water circulation through hydrothermal systems. We find that magnesium and solid-phase extractable DOC concentrations are correlated, suggesting that solid-phase extractable DOC is almost entirely lost from solution through mineralization or deposition during circulation through hydrothermal vents with fluid temperatures of 212-401 °C. In laboratory experiments, where we heated samples to 380 °C for four days, we found a similar removal efficiency. We conclude that thermal degradation alone can account for the loss of solid-phase extractable DOC in natural hydrothermal systems, and that its maximum lifetime is constrained by the timescale of hydrothermal cycling, at about 40 million years (Elderfield and Schultz, 1996, doi:10.1146/annurev.earth.24.1.191).
    Keywords: Akademik Mstislav Keldysh; AMK47; AMK47-Lost_City; AT18-08; Atlantis (1997); Carbon, organic, dissolved; Carbon, organic, dissolved, extracted; Comment; Comment 2 (continued); Contamination; CTD/Rosette; CTD-RO; Description; Error; Event label; Factor; Identification; ISIS; ISIS MS2000; J2-574; J2-575; J2-576; J2-579; J2-580; J2-581; J2-583; James Cook; JC042; JC080; JC082; JC42_ISIS_130; JC42_ISIS_133; JC42_ISIS_134; JC42_ISIS_141; JC80_015_CTD; JC80_ISIS_189; JC80_ISIS_190; JC80_ISIS_194; JC82_ISIS_198; JC82_ISIS_200; JC82_ISIS_202; JC82_ISIS_204; JC82_ISIS_206; JC82_ISIS_207; Juan_de_Fuca_Ridge_Axial; Juan_de_Fuca_Ridge_Endeavour; Latitude of event; Lithology/composition/facies; Longitude of event; Lost City Hydrothermal Field, Mid-Atlantic Ridge; M82/3; M82/3_719-1; M82/3_722-1; M82/3_739-1; M82/3_756-1; Magnesium; Maria S. Merian; Meteor (1986); MIR; MIR deep-sea manned submersible; MSM10/3; MSM10/3_290ROV-11; MSM10/3_300; MSM10/3_313ROV-12; Name; Ocean and sea region; Percentage; Precision; Remote operated vehicle; Remote operated vehicle Jason II; ROV; ROVJ; Sample type; Sample volume; Sampling date; Site; Solid phase extractable; South Atlantic Ocean; tropical/subtropical North Atlantic; Type; Volume; Wakamiko_Crater
    Type: Dataset
    Format: text/tab-separated-values, 4130 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2022-05-25
    Description: Author Posting. © National Academy of Sciences, 2006. This article is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences 103 (2006): 6448-6453, doi:10.1073/pnas.0600830103.
    Description: Submersible exploration of the Samoan hotspot revealed a new, 300-m-tall, volcanic cone, named Nafanua, in the summit crater of Vailulu'u seamount. Nafanua grew from the 1,000-m-deep crater floor in 〈4 years and could reach the sea surface within decades. Vents fill Vailulu'u crater with a thick suspension of particulates and apparently toxic fluids that mix with seawater entering from the crater breaches. Low-temperature vents form Fe oxide chimneys in many locations and up to 1-m-thick layers of hydrothermal Fe floc on Nafanua. High-temperature (81°C) hydrothermal vents in the northern moat (945-m water depth) produce acidic fluids (pH 2.7) with rising droplets of (probably) liquid CO2. The Nafanua summit vent area is inhabited by a thriving population of eels (Dysommina rugosa) that feed on midwater shrimp probably concentrated by anticyclonic currents at the volcano summit and rim. The moat and crater floor around the new volcano are littered with dead metazoans that apparently died from exposure to hydrothermal emissions. Acid-tolerant polychaetes (Polynoidae) live in this environment, apparently feeding on bacteria from decaying fish carcasses. Vailulu'u is an unpredictable and very active underwater volcano presenting a potential long-term volcanic hazard. Although eels thrive in hydrothermal vents at the summit of Nafanua, venting elsewhere in the crater causes mass mortality. Paradoxically, the same anticyclonic currents that deliver food to the eels may also concentrate a wide variety of nektonic animals in a death trap of toxic hydrothermal fluids.
    Description: This work was supported by the National Oceanic and Atmospheric Administration (NOAA) Oceans Exploration and the Hawaii Undersea Research Laboratory–NOAA Undersea Research Program, the National Science Foundation, the Australian Research Council, and the SERPENT program.
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: 5598800 bytes
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2022-05-25
    Description: Author Posting. © American Geophysical Union, 2007. 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 8 (2007): Q08013, doi:10.1029/2007GC001652.
    Description: We report first evidence for hydrothermal activity from the southern Knipovich Ridge, an ultra-slow spreading ridge segment in the Norwegian-Greenland Sea. Evidence comes from optical backscatter anomalies collected during a systematic side-scan sonar survey of the ridge axis, augmented by the identification of biogeochemical tracers in the overlying water column that are diagnostic of hydrothermal plume discharge (Mn, CH4, ATP). Analysis of coregistered geologic and oceanographic data reveals that the signals we have identified are consistent with a single high-temperature hydrothermal source, located distant from any of the axial volcanic centers that define second-order segmentation along this oblique ridge system. Rather, our data indicate a hydrothermal source associated with highly tectonized seafloor that may be indicative of serpentinizing ultramafic outcrops. Consistent with this hypothesis, the hydrothermal plume signals we have detected exhibit a high methane to manganese ratio of 2–3:1. This is higher than that typical of volcanically hosted vent sites and provides further evidence that the source of the plume signals reported here is most probably a high-temperature hydrothermal field that experiences some ultramafic influence (compare to Rainbow and Logachev sites, Mid-Atlantic Ridge). While such sites have previously been invoked to be common on the SW Indian Ridge, this may be the first such site to be located along the Arctic ultra-slow spreading ridge system.
    Description: Connelly and German were funded by NERC grant NER/B/S/ 2000/00755, NERC Core Strategic Funding at NOC, and the ChEss project of the Census of Marine Life.
    Keywords: Hydrothermal ; Arctic ; Serpentinization ; Knipovich Ridge
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2022-05-25
    Description: © Macmillan Publishers Limited, 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Nature Communications 3 (2012): 620, doi:10.1038/ncomms1636.
    Description: The Mid-Cayman spreading centre is an ultraslow-spreading ridge in the Caribbean Sea. Its extreme depth and geographic isolation from other mid-ocean ridges offer insights into the effects of pressure on hydrothermal venting, and the biogeography of vent fauna. Here we report the discovery of two hydrothermal vent fields on the Mid-Cayman spreading centre. The Von Damm Vent Field is located on the upper slopes of an oceanic core complex at a depth of 2,300 m. High-temperature venting in this off-axis setting suggests that the global incidence of vent fields may be underestimated. At a depth of 4,960 m on the Mid-Cayman spreading centre axis, the Beebe Vent Field emits copper-enriched fluids and a buoyant plume that rises 1,100 m, consistent with 〉 400 °C venting from the world’s deepest known hydrothermal system. At both sites, a new morphospecies of alvinocaridid shrimp dominates faunal assemblages, which exhibit similarities to those of Mid-Atlantic vents.
    Description: This work is supported by a UK NERC award (NE/F017774/1 & NE/F017758/1) to J.T.C., D.P.C., B.J.M., K.S. and P.A.T., Royal Society Travel Grant 2009/R3 to R.C.S., A.M. is supported by SENSEnet, a Marie Curie Initial Training Network (ITN) funded by the European Commission Seventh Framework Programme, Contract Number PITN-GA-2009-237868 and a NASA ASTEP Grant NNX09AB75G to C.R.G. and C.L.V.D., which are gratefully acknowledged.
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2022-05-25
    Description: © The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS Biology 10 (2012): e1001234, doi:10.1371/journal.pbio.1001234.
    Description: Since the first discovery of deep-sea hydrothermal vents along the Galápagos Rift in 1977, numerous vent sites and endemic faunal assemblages have been found along mid-ocean ridges and back-arc basins at low to mid latitudes. These discoveries have suggested the existence of separate biogeographic provinces in the Atlantic and the North West Pacific, the existence of a province including the South West Pacific and Indian Ocean, and a separation of the North East Pacific, North East Pacific Rise, and South East Pacific Rise. The Southern Ocean is known to be a region of high deep-sea species diversity and centre of origin for the global deep-sea fauna. It has also been proposed as a gateway connecting hydrothermal vents in different oceans but is little explored because of extreme conditions. Since 2009 we have explored two segments of the East Scotia Ridge (ESR) in the Southern Ocean using a remotely operated vehicle. In each segment we located deep-sea hydrothermal vents hosting high-temperature black smokers up to 382.8°C and diffuse venting. The chemosynthetic ecosystems hosted by these vents are dominated by a new yeti crab (Kiwa n. sp.), stalked barnacles, limpets, peltospiroid gastropods, anemones, and a predatory sea star. Taxa abundant in vent ecosystems in other oceans, including polychaete worms (Siboglinidae), bathymodiolid mussels, and alvinocaridid shrimps, are absent from the ESR vents. These groups, except the Siboglinidae, possess planktotrophic larvae, rare in Antarctic marine invertebrates, suggesting that the environmental conditions of the Southern Ocean may act as a dispersal filter for vent taxa. Evidence from the distinctive fauna, the unique community structure, and multivariate analyses suggest that the Antarctic vent ecosystems represent a new vent biogeographic province. However, multivariate analyses of species present at the ESR and at other deep-sea hydrothermal vents globally indicate that vent biogeography is more complex than previously recognised.
    Description: The ChEsSo research programme was funded by a NERC Consortium Grant (NE/DO1249X/1) and supported by the Census of Marine Life and the Sloan Foundation, and the Total Foundation for Biodiversity (Abyss 2100)(SVTH) all of which are gratefully acknowledged. We also acknowledge NSF grant ANT-0739675 (CG and TS), NERC PhD studentships NE/D01429X/1(LH, LM, CNR), NE/H524922/1(JH) and NE/F010664/1 (WDKR), a Cusanuswerk doctoral fellowship, and a Lesley & Charles Hilton-Brown Scholarship, University of St. Andrews (PHBS).
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2021-12-15
    Description: We detected a controlled release of CO2 (g) with pH eddy covariance. We quantified CO2 emission using measurements of water velocity and pH in the plume of aqueous CO2 generated by the bubble streams, and using model predictions of vertical CO2 dissolution and its dispersion downstream. CO2 (g) was injected 3 m below the floor of the North Sea at rates of 5.7–143 kg d-1. Instruments were 2.6 m from the center of the bubble streams. In the absence of injected CO2, pH eddy covariance quantified the proton flux due to naturally-occurring benthic organic matter mineralization (equivalent to a dissolved inorganic carbon flux of 7.6 ± 3.3 mmol m-2 d-1, s.e., n = 33). At the lowest injection rate, the proton flux due to CO2 dissolution was 20-fold greater than this. To accurately quantify emission, the kinetics of the carbonate system had to be accounted for. At the peak injection rate, 73 ± 13% (s.d.) of the injected CO2 was emitted, but when kinetics were neglected, the calculated CO2 emission was one-fifth of this. Our results demonstrate that geochemical techniques can detect and quantify very small seafloor sources of CO2 and attribute them to natural or abiotic origins.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev , info:eu-repo/semantics/article
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2021-12-15
    Description: Carbon capture and storage (CCS) is a key technology to reduce carbon dioxide (CO2) emissions from industrial processes in a feasible, substantial, and timely manner. For geological CO2 storage to be safe, reliable, and accepted by society, robust strategies for CO2 leakage detection, quantification and management are crucial. The STEMM-CCS (Strategies for Environmental Monitoring of Marine Carbon Capture and Storage) project aimed to provide techniques and understanding to enable and inform cost-effective monitoring of CCS sites in the marine environment. A controlled CO2 release experiment was carried out in the central North Sea, designed to mimic an unintended emission of CO2 from a subsurface CO2 storage site to the seafloor. A total of 675 kg of CO2 were released into the shallow sediments (~3 m below seafloor), at flow rates between 6 and 143 kg/d. A combination of novel techniques, adapted versions of existing techniques, and well-proven standard techniques were used to detect, characterise and quantify gaseous and dissolved CO2 in the sediments and the overlying seawater. This paper provides an overview of this ambitious field experiment. We describe the preparatory work prior to the release experiment, the experimental layout and procedures, the methods tested, and summarise the main results and the lessons learnt.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev , info:eu-repo/semantics/article
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2022-05-26
    Description: © The Author(s), 2014. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Geochimica et Cosmochimica Acta 139 (2014): 47-71, doi:10.1016/j.gca.2014.04.024.
    Description: The East Scotia Ridge is an active back-arc spreading centre located to the west of the South Sandwich island arc in the Southern Ocean. Initial exploration of the ridge by deep-tow surveys provided the first evidence for hydrothermal activity in a back-arc setting outside of the western Pacific, and we returned in 2010 with a remotely operated vehicle to precisely locate and sample hydrothermal sites along ridge segments E2 and E9. Here we report the chemical and isotopic composition of high- and low-temperature vent fluids, and the mineralogy of associated high-temperature chimney material, for two sites at E2 (Dog’s Head and Sepia), and four sites at E9 (Black & White, Ivory Tower, Pagoda and Launch Pad). The chemistry of the fluids is highly variable between the ridge segments. Fluid temperatures were ∼350 °C at all vent sites except Black & White, which was significantly hotter (383 °C). End-member chloride concentrations in E2 fluids (532–536 mM) were close to background seawater (540 mM), whereas Cl in E9 fluids was much lower (98–220 mM) indicating that these fluids are affected by phase separation. Concentrations of the alkali elements (Na, Li, K and Cs) and the alkaline earth elements (Ca, Sr and Ba) co-vary with Cl, due to charge balance constraints. Similarly, concentrations of Mn and Zn are highest in the high Cl fluids but, by contrast, Fe/Cl ratios are higher in E9 fluids (3.8–8.1 × 10−3) than they are in E2 fluids (1.5–2.4 × 10−3) and fluids with lowest Cl have highest Cu. Although both ridge segments are magmatically inflated, there is no compelling evidence for input of magmatic gases to the vent fluids. Fluid δD values range from 0.2‰ to 1.5‰, pH values (3.02–3.42) are not especially low, and F concentrations (34.6–54.4 μM) are lower than bottom seawater (62.8 μM). The uppermost sections of conjugate chimney material from E2, and from Ivory Tower and Pagoda at E9, typically exhibit inner zones of massive chalcopyrite enclosed within an outer zone of disseminated sulphide, principally sphalerite and pyrite, in an anhydrite matrix. By contrast, the innermost part of the chimneys that currently vent fluids with lowest Cl (Black & White and Launch Pad), is dominated by anhydrite. By defining and assessing the controls on the chemical composition of these vent fluids, and associated mineralisation, this study provides new information for evaluating the significance of hydrothermal processes at back-arc basins for ocean chemistry and the formation of seafloor mineral deposits.
    Description: This work was funded by the Natural Environment Research Council consortium grant NE/D01249X/1. C.R.G. acknowledges further support from the National Science Foundation’s Office of Polar Programs grant ANT-0739675. N.R.B. acknowledges funding from the National Sciences and Engineering Research Council of Canada, Ontario Ministry of Research and Innovation, and the Academic Development Fund at Western University.
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...