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
  • PANGAEA  (7)
  • AGU (American Geophysical Union)  (3)
Document type
Keywords
Years
  • 1
    facet.materialart.
    Unknown
    PANGAEA
    In:  Supplement to: Berndt, Christian; Feseker, Tomas; Treude, Tina; Krastel, Sebastian; Liebetrau, Volker; Niemann, Helge; Bertics, Victoria J; Dumke, Ines; Dünnbier, Karolin; Ferre, Benedicte; Graves, Carolyn; Gross, Felix; Hissmann, Karen; Hühnerbach, Veit; Krause, Stefan; Lieser, Kathrin; Schauer, Jürgen; Steinle, Lea (2014): Temporal constraints on hydrate-controlled methane seepage off Svalbard. Published Online January 2 2014, Science, https://doi.org/10.1126/science.1246298
    Publication Date: 2023-03-03
    Description: Methane hydrate is an ice-like substance that is stable at high-pressure and low temperature in continental margin sediments. Since the discovery of a large number of gas flares at the landward termination of the gas hydrate stability zone off Svalbard, there has been concern that warming bottom waters have started to dissociate large amounts of gas hydrate and that the resulting methane release may possibly accelerate global warming. Here, we can corroborate that hydrates play a role in the observed seepage of gas, but we present evidence that seepage off Svalbard has been ongoing for at least three thousand years and that seasonal fluctuations of 1-2°C in the bottom-water temperature cause periodic gas hydrate formation and dissociation, which focus seepage at the observed sites.
    Keywords: Center for Marine Environmental Sciences; GEOMAR; Helmholtz Centre for Ocean Research Kiel; MARUM
    Type: Dataset
    Format: application/zip, 29 datasets
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2023-04-24
    Description: Deep-sea sediment samples were taken from the (wider) Kairei hydrothermal field area (25°S, 70°E) as well as a remote site (26°S, 71°E) in the Indian Ocean during the INDEX cruise 2016 with the N/O Pourquoi pas? (Ifremer, France). Push core samples from different areas of the Kairei vent field, as well as a sample from the remote site (~200 km south-east from the Kairei), were recovered with the help of the ROV VICTOR 6000 (Ifremer, France). All subsampling steps were carried out shipboard at 4 °C. With sterile syringes (nozzles removed) 3 ml of 2 cm layers of sediment were transferred into sterile falcon tubes for DNA extraction and stored at –80 °C. The remaining sediment was cut into 2 cm slices, freeze-dried, and partially milled to 〈75 mm for geochemical analyses. The sediment was analyzed for carbon chemistry, i.e. total organic carbon (TOC) and total inorganic carbon (TIC) with routine standard methods (IR-detection after combustion, ISO 10694, LECO CS 230 analyzer). Elemental composition of Kairei sediments was estimated by the accredited Actlab Laboratories, Canada (Multimethod mix called Ultratrace 3 program, using INAA, 4-Acid Digestion, ICP-OES, and ICP-MS). Sediments from the remote station were analyzed by routine WD-XRF after fusion with Li-Metaborate/Li-Bromide (XRF spectrometers Philips PW 2400 und Philips PW 1480).
    Keywords: 16S rRNA gene tags; Aluminium oxide; Area/locality; Calcium oxide; Carbon, carbonate; Carbon, organic; Carbon, total; Depth, bottom/max; DEPTH, sediment/rock; Depth, top/min; Element Analyser CS, LECO CS 230; Event label; geochemistry of porewaters; hydrothermal vent; INDEX2016; INDEX2016_12ROV; INDEX2016_20ROV; Indian Ocean; Iron oxide, Fe2O3; Kairei field; Magnesium oxide; Manganese oxide; metalliferous sediments; Phosphorus pentoxide; Potassium oxide; Pourquoi Pas ? (2005); Sample code/label; Silicon dioxide; Sodium oxide; Sulfur, total; Titanium dioxide; VICTOR; Victor6000 ROV
    Type: Dataset
    Format: text/tab-separated-values, 628 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2023-03-02
    Description: Deep-sea sediment samples were taken from the (wider) Kairei hydrothermal field area (25°S, 70°E) as well as a remote site (26°S, 71°E) in the Indian Ocean during the INDEX cruise 2016 with the N/O Pourquoi pas? (Ifremer, France). Push core samples from different areas of the Kairei vent field, as well as a sample from the remote site (~200 km south-east from the Kairei), were recovered with the help of the ROV VICTOR 6000 (Ifremer, France). All subsampling steps were carried out shipboard at 4 °C. Porewater from push cores was extracted with rhizons (CSS, 5 cm Rhizosphere Research Products B.V., Netherlands) at a resolution of 2-3 cm, fixed with 1% HNO3 for trace element analyses and stored at 4 °C. With sterile syringes (nozzles removed) 3 ml of 2 cm layers of sediment were transferred into sterile falcon tubes for DNA extraction and stored at –80 °C. Concentrations of minor and trace elements Li, Al, Rb, Cs, Sr, Ba, V, Mn, Fe, Co, Ni, Cu, Zn, Ag, Cd, Tl, Pb, In, Sn, Sb, Bi, W, Mo, U, Au, As, and L were determined by highresolution ICP-SF-MS (Element XR, Thermo Scientific) after 25-fold dilution and spiking with Y and Re for internal standardization using appropriate mass resolution settings.
    Keywords: 16S rRNA gene tags; Aluminium; Antimony; Area/locality; Arsenic; Barium; Cadmium; Caesium; Cerium; Cobalt; Copper; DEPTH, sediment/rock; Europium; Event label; geochemistry of porewaters; hydrothermal vent; ICP-OES; ICP-SF-MS, Thermo Scientific, Element XR; INDEX2016; INDEX2016_12ROV; INDEX2016_20ROV; Indian Ocean; Ion chromatography; Iron; Kairei field; Lanthanum; Lead; Manganese; metalliferous sediments; Molybdenum; Neodymium; Nickel; Nitrate; Pourquoi Pas ? (2005); Praseodymium; Samarium; Sample code/label; Silica, dissolved; Silver; Thallium; Tin; Tungsten; Uranium; Vanadium; VICTOR; Victor6000 ROV; Zinc
    Type: Dataset
    Format: text/tab-separated-values, 942 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2024-02-02
    Description: This gravity corer was taken in the methane seep area off northwestern Svalbard at the gas hydrate stability limit. Sediment was sampled to determine solutes of sediment porewater, sediment wet and dry parameters and microbial activity (sulfate reduction and anaerobic oxidation of methane).
    Keywords: Alkalinity, total; Ammonium; Bromide; Calcium carbonate; Carbon, inorganic, total; Carbon, organic, total; Carbon, total; Carbon/Nitrogen ratio; Chloride; Density; DEPTH, sediment/rock; GC; Geochemistry; Gravity corer; hydrates; Hydrogen sulfide; Maria S. Merian; Methane; Methane, oxidation rate, anaerobic; methane oxidation; MSM21/4; MSM21/4_657-1; Nitrite; Nitrogen, organic; North Greenland Sea; Porosity; Sulfate; Sulfate reduction rate; Sulfur, total; Svalbard; δ18O
    Type: Dataset
    Format: text/tab-separated-values, 289 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2024-02-02
    Description: Six peepers were deployed by the German submersible Jago in sediment of the methane seep area off northwestern Svalbard at the gas hydrate stability limit. Peeper 1 and 2 were deployed in a sulfur bacteria mat, Peeper 3 and 4 were in a siboglinid (pogonophoran) worm field, and Peeper 5 and 6 were at a gas vent. The distance between the three groups was about 1 meter. After 10 days incubation, peeper were retrieved and porewater solutes were measured in the peeper samples.
    Keywords: Alkalinity, total; Bromide; Chamber number; Chloride; DEPTH, sediment/rock; Geochemistry; Hydrogen sulfide; JAGO; Maria S. Merian; Methane; MSM21/4; MSM21/4_647-1; North Greenland Sea; Number; sediment porewater; Submersible JAGO; Sulfate; Svalbard
    Type: Dataset
    Format: text/tab-separated-values, 321 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2024-02-02
    Keywords: Age, dated; Age, error; Age model; Calculated; Carbonates; Depth, bottom/max; DEPTH, sediment/rock; Depth, top/min; Description; Error, absolute; Event label; JAGO; Latitude of event; Location; Longitude of event; Maria S. Merian; Mass spectrometer, Finnigan, MAT 253; MC-ICP-MS, isotope dilution; MSM21/4; MSM21/4_579-1; MSM21/4_597-1; non-silicates, total; North Greenland Sea; Sample code/label; Sample mass; Submersible JAGO; Thorium-230/Thorium-232 activity ratio; Thorium-230/Uranium-234 activity ratio; Thorium-232; Uranium-234/Uranium-238 activity ratio; Uranium-234/Uranium-238 activity ratio, error, absolute; Uranium-238; Uranium-238/Thorium-232 activity ratio; X-ray diffractometry (Philips PW1710); δ13C, carbonate; δ18O, carbonate
    Type: Dataset
    Format: text/tab-separated-values, 119 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2024-02-02
    Keywords: Age, dated; Age, error; Age model; Calculated; Carbonates; Depth, bottom/max; DEPTH, sediment/rock; Depth, top/min; Description; Error, absolute; GC; Gravity corer; Location; Maria S. Merian; Mass spectrometer, Finnigan, MAT 253; MC-ICP-MS, isotope dilution; MSM21/4; MSM21/4_657-1; non-silicates, total; North Greenland Sea; Sample code/label; Sample mass; Thorium-230/Thorium-232 activity ratio; Thorium-230/Uranium-234 activity ratio; Thorium-232; Uranium-234/Uranium-238 activity ratio; Uranium-234/Uranium-238 activity ratio, error, absolute; Uranium-238; Uranium-238/Thorium-232 activity ratio; X-ray diffractometry (Philips PW1710); δ13C, carbonate; δ18O, carbonate
    Type: Dataset
    Format: text/tab-separated-values, 281 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    facet.materialart.
    Unknown
    AGU (American Geophysical Union) | Wiley
    In:  Geophysical Research Letters, 43 (10). pp. 5225-5232.
    Publication Date: 2019-02-01
    Description: We show that inflows of oxygenated waters into sulfidic layers have a strong impact on biogeochemical transformation at oxic/anoxic transition zones. Taking the pelagic methane dynamics in the Gotland Basin as an example, we performed our studies when one of the largest inflows ever recorded entered the Baltic Sea in March 2015. An inflowing gravity current transported oxic waters into the sulfidic deep layers and freshly generated a near-bottom secondary redox interface. At the upper slope, where the inflowing water masses were vigorously turbulent and the main and secondary redox interfaces in close contact to each other, methane oxidation rates inside the transition zone were found to be higher compared to the weakly turbulent basin interior. At the main redox interface in the basin center, lateral intrusions of oxygenated waters into intermediate water depth may have stimulated the growth of the methanotrophic community and their activity.
    Type: Article , PeerReviewed
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2023-02-08
    Description: A site at the gas hydrate stability limit was investigated offshore northwestern Svalbard to study methane transport in sediment. The site was characterized by chemosynthetic communities (sulfur bacteria mats, tubeworms) and gas venting. Sediments were sampled with in‐situ porewater collectors and by gravity coring followed by analyses of porewater constituents, sediment and carbonate geochemistry, and microbial activity, taxonomy, and lipid biomarkers. Sulfide and alkalinity concentrations showed concentration maxima in near‐surface sediments at the bacterial mat and deeper maxima at the gas vent site. Sediments at the periphery of the chemosynthetic field were characterized by two sulfate‐methane transition zones (SMTZ) at ~204 and 45 cm depth, where activity maxima of microbial anaerobic oxidation of methane (AOM) with sulfate were found. Amplicon sequencing and lipid biomarker indicate that AOM at the SMTZs was mediated by ANME‐1 archaea. A 1D numerical transport reaction model suggests that the deeper SMTZ‐1 formed on centennial scale by vertical advection of methane, while the shallower SMTZ‐2 could only be reproduced by non‐vertical methane injections starting on decadal scale. Model results were supported by age distribution of authigenic carbonates, showing youngest carbonates within SMTZ‐2. We propose that non‐vertical methane injection was induced by increasing blockage of vertical transport or formation of sediment fractures. Our study further suggests that the methanotrophic response to the non‐vertical methane injection was commensurate with new methane supply. This finding provides new information about for the response time and efficiency of the benthic methane filter in environments with fluctuating methane transport.
    Type: Article , PeerReviewed
    Format: text
    Format: video
    Format: text
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2024-02-07
    Description: Subsurface flows, particularly hyporheic exchange fluxes, driven by streambed topography, permeability, channel gradient and dynamic flow conditions provide prominent ecological services such as nitrate removal from streams and aquifers. Stream flow dynamics cause strongly nonlinear and often episodic contributions of nutrient concentrations in river-aquifer systems. Using a fully coupled transient flow and reactive transport model, we investigated the denitrification potential of hyporheic zones during peak-flow events. The effects of streambed permeability, channel gradient and bedform amplitude on the spatio-temporal distribution of nitrate and dissolved organic carbon in streambeds and the associated denitrification potential were explored. Distinct peak-flow events with different intensity, duration and hydrograph shape were selected to represent a wide range of peak-flow scenarios. Our results indicated that the specific hydrodynamic characteristics of individual flow events largely determine the average positive or negative nitrate removal capacity of hyporheic zones, however the magnitude of this capacity is controlled by geomorphological settings (i.e. channel slope, streambed permeability and bedform amplitude). Specifically, events with longer duration and higher intensity were shown to promote higher nitrate removal efficiency with higher magnitude of removal efficiency in the scenarios with higher slope and permeability values. These results are essential for better assessment of the subsurface nitrate removal capacity under the influence of flow dynamics and particularly peak-flow events in order to provide tailored solutions for effective restoration of interconnected river-aquifer systems.
    Type: Article , PeerReviewed , info:eu-repo/semantics/article
    Format: text
    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...