ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
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
  • Center for Marine Environmental Sciences; MARUM  (16)
  • Tin
Collection
Keywords
Publisher
Years
  • 1
    Electronic Resource
    Electronic Resource
    Synthesis of (RSn)4X6 Adamantanes (X = O, S, Se) in Liquid Ammonia and in the Two-Phase System Liquid Ammonia/THF (1999)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 1999 (1999), S. 869-872 
    Details
    ISSN: 1434-1948
    Keywords: Adamantane ; Liquid ammonia ; Oxygen ; Sulfur and selenium ; Tin ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions of trisSnBr3 (1) [tris = (Me3Si)3C] and nBuSnCl3 with Na2X (X = O, S, Se) yield the heterocyclic adamantanes 2-6. The reaction of 1 with Na2O is carried out in liquid ammonia under normal pressure at -78 °C to give (trisSn)4O6 (2). However, the reaction of 1 with Na2S and Na2Se under pressure at room temperature results in the formation of (trisSn)4S6 (3) and (trisSn)4Se6 (4). nBuSnCl3 reacts with Na2S and Na2Se in liquid ammonia at -33 °C under normal pressure to give (nBuSn)4S6 (5) and (nBuSn)4Se6 (6), respectively.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 2
    facet.materialart.
    Unknown
    Hydrocarbon analyses of submarine mud volcanoes (MV) in the Kumano forearc basin (2014)
    PANGAEA
    In:  Supplement to: Pape, Thomas; Geprägs, Patrizia; Hammerschmidt, Sebastian; Wintersteller, Paul; Wei, Jiangong; Fleischmann, Timo; Bohrmann, Gerhard; Kopf, Achim J (2014): Hydrocarbon seepage and its sources at mud volcanoes of the Kumano forearc basin, Nankai Trough subduction zone. Geochemistry, Geophysics, Geosystems, 15(6), 2180-2194, https://doi.org/10.1002/2013GC005057
    Details
    Publication Date: 2023-03-03
    Description: Twelve submarine mud volcanoes (MV) in the Kumano forearc basin within the Nankai Trough subduction zone were investigated for hydrocarbon origins and fluid dynamics. Gas hydrates diagnostic for methane concentrations exceeding solubilities were recovered from MVs 2, 4, 5, and 10. Molecular ratios (C1/C2〈250) and stable carbon isotopic compositions (d13C-CH4 〉-40 per mil V-PDB) indicate that hydrate-bound hydrocarbons (HCs) at MVs 2, 4, and 10 are derived from thermal cracking of organic matter. Considering thermal gradients at the nearby IODP Sites C0009 and C0002, the likely formation depth of such HCs ranges between 2300 and 4300 m below seafloor (mbsf). With respect to basin sediment thickness and the minimum distance to the top of the plate boundary thrust we propose that the majority of HCs fueling the MVs is derived from sediments of the Cretaceous to Tertiary Shimanto belt below Pliocene/Pleistocene to recent basin sediments. Considering their sizes and appearances hydrates are suggested to be relicts of higher MV activity in the past, although the sporadic presence of vesicomyid clams at MV 2 showed that fluid migration is sufficient to nourish chemosynthesis-based organisms in places. Distributions of dissolved methane at MVs 3, 4, 5, and 8 pointed at fluid supply through one or few MV conduits and effective methane oxidation in the immediate subsurface. The aged nature of the hydrates suggests that the major portion of methane immediately below the top of the methane-containing sediment interval is fueled by current hydrate dissolution rather than active migration from greater depth.
    Keywords: Center for Marine Environmental Sciences; MARUM
    Type: Dataset
    Format: application/zip, 31 datasets
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
  • 3
    facet.materialart.
    Unknown
    In-situ sediment temperature and pore water chloride concentration at pockmarks of the Nigerian continental margin (2015)
    PANGAEA
    In:  Supplement to: Wei, Jiangong; Pape, Thomas; Sultan, Nabil; Colliat, Jean-Louis; Himmler, Tobias; Ruffine, Livio; de Prunelé, Alexis; Dennielou, Bernard; Garziglia, Sebastien; Marsset, Tania; Peters, Carl A; Rabiu, Abdulkarim; Bohrmann, Gerhard (2015): Gas hydrate distributions in sediments of pockmarks from the Nigerian margin – Results and interpretation from shallow drilling. Marine and Petroleum Geology, 59, 359-370, https://doi.org/10.1016/j.marpetgeo.2014.09.013
    Details
    Publication Date: 2023-03-03
    Description: A joint research expedition between the French IFREMER and the German MARUM was conducted in 2011 using the R/V 'Pourquoi pas?' to study gas hydrate distributions in a pockmark field (1141-1199 m below sea surface) at the continental margin of Nigeria. The seafloor drill rig MeBo of MARUM was used to recover sediments as deep as 56.74 m below seafloor. The presence of gas hydrates in specific core sections was deduced from temperature anomalies recorded during continuous records of infrared thermal scanning and anomalies in pore water chloride concentrations. In situ sediment temperature measurements showed elevated geothermal gradients of up to 258 °C/km in the center of the so-called pockmark A which is up to 4.6 times higher than that in the background sediment (72 °C/km). The gas hydrate distribution and thermal regime in the pockmark are largely controlled by the intensity, periodicity and direction of fluid flow. The joint interaction between fluid flow, gas hydrate formation and dissolution, and the thermal regime governs pockmark formation and evolution on the Nigerian continental margin.
    Keywords: Center for Marine Environmental Sciences; MARUM
    Type: Dataset
    Format: application/zip, 13 datasets
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
  • 4
    facet.materialart.
    Unknown
    Multichannel seismic, acoustic and bathymetric data from the Lower Congo Basin (2017)
    PANGAEA
    In:  Supplement to: Wenau, Stefan; Spieß, Volkhard; Pape, Thomas; Fekete, Noemi (2017): Controlling mechanisms of giant deep water pockmarks in the Lower Congo Basin. Marine and Petroleum Geology, 83, 140-157, https://doi.org/10.1016/j.marpetgeo.2017.02.030
    Details
    Publication Date: 2023-03-03
    Description: Effective seal breaching is a major contributor to methane seepage from deep sea sediments as it ensures the migration of gas and liquid hydrocarbons from buried reservoirs to the seafloor. This study shows two giant pockmarks on the lower slope of the Lower Congo Basin associated with salt-tectonic faulting and the buried Pliocene Congo deep sea fan. The progressive burial of Pliocene fan deposits results in mobilization of methane from gas hydrates at the Base of the Gas Hydrate Stability Zone which migrates through the hemipelagic seal towards the seafloor along salt-induced faults. Seal-breaching in this part of the Lower Congo Basin relies solely on salt-tectonic faulting contrasting with upslope seafloor seepage settings where polygonal faulting within the hemipelagic seal occurs. Dedicated 2D and 3D seismic and acoustic surveying allows the detailed reconstruction of the evolution of pockmarks which appear to have been active for the last 640 kyr. We also show indications that the modern seafloor depression formed due to reduced sedimentation in the vicinity of active seepage. The presented seafloor seepage features illustrate the mode of gas release from the Pliocene fan in the Lower Congo Basin, which contrasts with previously investigated seepage environments further upslope.
    Keywords: Center for Marine Environmental Sciences; MARUM
    Type: Dataset
    Format: application/zip, 8 datasets
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
  • 5
    facet.materialart.
    Unknown
    Temperature, chloride and sulfate measurements of samples from RV METEOR cruise M112 (2017)
    PANGAEA
    In:  Supplement to: Loher, Markus; Pape, Thomas; Marcon, Yann; Römer, Miriam; Wintersteller, Paul; Praeg, Daniel; Torres, Marta E; Sahling, Heiko; Bohrmann, Gerhard (2018): Mud extrusion and ring-fault gas seepage – upward branching fluid discharge at a deep-sea mud volcano. Scientific Reports, 8, 6275, https://doi.org/10.1038/s41598-018-24689-1
    Details
    Publication Date: 2023-03-03
    Description: Submarine mud volcanoes release sediments and gas-rich fluids at the seafloor via deeply-rooted plumbing systems that remain poorly understood. Here the functioning of Venere mud volcano, on the Calabrian accretionary prism in ~1,600 m water depth is investigated, based on multi-parameter hydroacoustic and visual seafloor data obtained using ship-borne methods, ROVs, and AUVs. Two seepage domains are recognized: mud breccia extrusion from a summit, and hydrocarbon venting from peripheral sites, hosting chemosynthetic ecosystems and authigenic carbonates indicative of long-term seepage. Pore fluids in freshly extruded mud breccia (up to 13 °C warmer than background sediments) contained methane concentrations exceeding saturation by 2.7 times and chloride concentrations up to five times lower than ambient seawater. Gas analyses indicate an underlying thermogenic hydrocarbon source with potential admixture of microbial methane during migration along ring faults to the peripheral sites. The gas and pore water analyses point to fluids sourced deep (〉3 km) below Venere mud volcano. An upward-branching plumbing system is proposed to account for co-existing mud breccia extrusion and gas seepage via multiple surface vents that influence the distribution of seafloor ecosystems. This model of mud volcanism implies that methane-rich fluids may be released during prolonged phases of moderate activity.
    Keywords: Center for Marine Environmental Sciences; MARUM
    Type: Dataset
    Format: application/zip, 26 datasets
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
  • 6
    facet.materialart.
    Unknown
    Alkanes in fresh surface asphalts (2018)
    PANGAEA
    In:  Supplement to: Rubin-Blum, Maxim; Antony, Chakkiath Paul; Borowski, Christian; Sayavedra, Lizbeth; Pape, Thomas; Sahling, Heiko; Bohrmann, Gerhard; Kleiner, Manuel; Redmond, Molly C; Valentine, D L; Dubilier, Nicole (2017): Short-chain alkanes fuel mussel and sponge Cycloclasticus symbionts from deep-sea gas and oil seeps. Nature Microbiology, 2, 17093, https://doi.org/10.1038/nmicrobiol.2017.93
    Details
    Publication Date: 2023-03-03
    Description: Cycloclasticus bacteria are ubiquitous in oil-rich regions of the ocean and are known for their ability to degrade polycyclic aromatic hydrocarbons (PAHs). In this study, we describe Cycloclasticus that have established a symbiosis with Bathymodiolus heckerae mussels and poecilosclerid sponges from asphalt-rich, deep-sea oil seeps at Campeche Knolls in the southern Gulf of Mexico. Genomic and transcriptomic analyses revealed that, in contrast to all previously known Cycloclasticus, the symbiotic Cycloclasticus appears to lack the genes needed for PAH degradation. Instead, these symbionts use propane and other short-chain alkanes such as ethane and butane as carbon and energy sources, thus expanding the limited range of substrates known to power chemosynthetic symbioses. Analyses of short-chain alkanes in the environment of the Campeche Knolls symbioses revealed that these are present at high concentrations (in the μM to mM range). Comparative genomic analyses revealed high similarities between the genes used by the symbiotic Cycloclasticus to degrade short-chain alkanes and those of free-living Cycloclasticus that bloomed during the Deepwater Horizon oil spill. Our results indicate that the metabolic versatility of bacteria within the Cycloclasticus clade is higher than previously assumed, and highlight the expanded role of these keystone species in the degradation of marine hydrocarbons.
    Keywords: Center for Marine Environmental Sciences; MARUM
    Type: Dataset
    Format: application/zip, 2 datasets
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
  • 7
    facet.materialart.
    Unknown
    Geochemistry of seep carbonates and of hydrocarbons entrapped in carbonates and in adjacent vent gases (2018)
    PANGAEA
    In:  Supplement to: Blumenberg, Martin; Pape, Thomas; Seifert, Richard; Bohrmann, Gerhard; Schlömer, Stefan (2018): Can hydrocarbons entrapped in seep carbonates serve as gas geochemistry recorder? Geo-Marine Letters, 38(2), 121-129, https://doi.org/10.1007/s00367-017-0522-6
    Details
    Publication Date: 2023-03-03
    Description: The geochemistry of seep gases is useful for an understanding of the local petroleum system. Here it was tested whether individual light hydrocarbons in seep gases are representatively entrapped in authigenic carbonates that formed near active seep sites. If applicable, it would be possible to extract geochemical information not only on the origin but also on the thermal maturity of the hydrocarbon source rocks from the gases entrapped in carbonates in the past. Respective data could be used for a better understanding of paleoenvironments and might directly serve as calibration point for, amongst others, petroleum system modeling. For this approach, (sub)-recent seep carbonates from the Black Sea (Paleodnjepr region and Batumi seep area), two sites of the Campeche Knoll region in the Gulf of Mexico, and the Venere mud volcano (Mediterranean Sea) were selected. These seep carbonates derive from sites for which geochemical data on the currently seeping gases exist. During treatment with phosphoric acid, methane and higher hydrocarbons were released from all carbonates, but in low concentrations. Compositional studies demonstrate that the ratio of methane to the sum of higher hydrocarbons (C1/(C2+C3)) is (partly strongly) positively biased in the entrapped gas fraction. δ13C values of C1 were determined for all samples and, for the samples from the Gulf of Mexico and the Mediterranean Sea, also of C2 and C3. The present dataset from six seep sites indicates that information on the seeped methane can be—although with a scatter of several permil—recorded in seep carbonate matrices, but other valuable information like the composition and δ13C of ethane and propane appears to be modified or lost during, for example, enclosure or at an early stage of diagenesis.
    Keywords: Center for Marine Environmental Sciences; MARUM
    Type: Dataset
    Format: application/zip, 2 datasets
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
  • 8
    facet.materialart.
    Unknown
    Pore water and solid phase data of two sediment cores obtained in the Makran area offshore pakistan during expedition M 74/3 in 2007 (2013)
    PANGAEA
    In:  Supplement to: Fischer, David; Mogollón, José M; Strasser, Michael; Pape, Thomas; Bohrmann, Gerhard; Fekete, Noemi; Spieß, Volkhard; Kasten, Sabine (2013): Subduction zone earthquake as potential trigger of submarine hydrocarbon seepage. Nature Geoscience, 6(8), 647-651, https://doi.org/10.1038/ngeo1886
    Details
    Publication Date: 2023-03-03
    Description: Methane, a potent greenhouse gas, is abundant in marine sediments**1, 2. Submarine seepage of methane-dominated hydrocarbons is heterogeneous in space and time, and mechanisms that can trigger episodic seep events are poorly understood**2, 3, 4. For example, critical gas pressures have been predicted to develop beneath impermeable sediments that bear gas hydrates, making them susceptible to mechanical failure and gas release**5, 6. Gas hydrates often occur in seismically active regions, but the role of earthquakes as triggers of hydrocarbon seepage through gas-hydrate-bearing sediments has been only superficially addressed**7, 8. Here we present geochemical analyses of sediment cores retrieved from the convergent margin off Pakistan. We find that a substantial increase in the upward flux of gas occurred within a few decades of a Mw 8.1 earthquake in 1945-the strongest earthquake reported for the Arabian Sea. Our seismic reflection data suggest that co-seismic shaking fractured gas-hydrate-bearing sediments, creating pathways for the free gas to migrate from a shallow reservoir within the gas hydrate stability zone into the water column. We conservatively estimate that 3.26×10**8 mol of methane have been discharged from the seep site since the earthquake. We therefore suggest that hydrocarbon seepage triggered by earthquakes needs to be considered in local and global carbon budgets at active continental margins.
    Keywords: Center for Marine Environmental Sciences; MARUM
    Type: Dataset
    Format: application/zip, 4 datasets
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
  • 9
    facet.materialart.
    Unknown
    Porosity of MeBo sediment cores from the continental margin off Svalbard - cruise MSM57 (2018)
    PANGAEA
    In:  Supplement to: Riedel, Michael; Wallmann, Klaus; Berndt, Christian; Pape, Thomas; Freudenthal, Tim; Bergenthal, Markus; Bünz, Stefan; Bohrmann, Gerhard (2018): In situ temperature measurements at the Svalbard continental margin: Implications for gas hydrate dynamics. Geochemistry, Geophysics, Geosystems, 19(4), 1165-1177, https://doi.org/10.1002/2017GC007288
    Details
    Publication Date: 2023-04-27
    Description: During expedition MARIA S. MERIAN MSM57/2 to the Svalbard margin offshore Prins Karls Forland, the seafloor drill rig MARUM‐MeBo70 was used to assess the landward termination of the gas hydrate system in water depths between 340 and 446 m. The study region shows abundant seafloor gas vents, clustered at a water depth of ∼400 m. The sedimentary environment within the upper 100 m below seafloor (mbsf) is dominated by ice‐berg scours and glacial unconformities. Sediments cored included glacial diamictons and sheet‐sands interbedded with mud. Seismic data show a bottom simulating reflector terminating ∼30 km seaward in ∼760 m water depth before it reaches the theoretical limit of the gas hydrate stability zone (GHSZ) at the drilling transect. We present results of the first in situ temperature measurements conducted with MeBo70 down to 28 mbsf. The data yield temperature gradients between ∼38°C km−1 at the deepest site (446 m) and ∼41°C km−1 at a shallower drill site (390 m). These data constrain combined with in situ pore‐fluid data, sediment porosities, and thermal conductivities the dynamic evolution of the GHSZ during the past 70 years for which bottom water temperature records exist. Gas hydrate is not stable in the sediments at sites shallower than 390 m water depth at the time of acquisition (August 2016). Only at the drill site in 446 m water depth, favorable gas hydrate stability conditions are met (maximum vertical extent of ∼60 mbsf); however, coring did not encounter any gas hydrates.
    Keywords: Center for Marine Environmental Sciences; MARUM
    Type: Dataset
    Format: application/zip, 7 datasets
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
  • 10
    facet.materialart.
    Unknown
    Porosity and methane stable carbon isotope values of MeBo sediment cores from the continental margin off Svalbard - cruise MSM57 (2018)
    PANGAEA
    In:  Supplement to: Wallmann, Klaus; Riedel, Michael; Hong, W L; Patton, H; Hubbard, Alun L; Pape, Thomas; Hsu, Chieh-Wei; Schmidt, Christiane; Johnson, J E; Torres, Marta E; Andreassen, Karin; Berndt, Christian; Bohrmann, Gerhard (2018): Gas hydrate dissociation off Svalbard induced by isostatic rebound rather than global warming. Nature Communications, 9(1), https://doi.org/10.1038/s41467-017-02550-9
    Details
    Publication Date: 2023-04-27
    Description: Methane seepage from the upper continental slopes of Western Svalbard has previously been attributed to gas hydrate dissociation induced by anthropogenic warming of ambient bottom waters. Here we show that sediment cores drilled off Prins Karls Foreland contain freshwater from dissociating hydrates. However, our modeling indicates that the observed pore water freshening began around 8 ka BP when the rate of isostatic uplift outpaced eustatic sea-level rise. The resultant local shallowing and lowering of hydrostatic pressure forced gas hydrate dissociation and dissolved chloride depletions consistent with our geochemical analysis. Hence, we propose that hydrate dissociation was triggered by postglacial isostatic rebound rather than anthropogenic warming. Furthermore, we show that methane fluxes from dissociating hydrates were considerably smaller than present methane seepage rates implying that gas hydrates were not a major source of methane to the oceans, but rather acted as a dynamic seal, regulating methane release from deep geological reservoirs.
    Keywords: Center for Marine Environmental Sciences; MARUM
    Type: Dataset
    Format: application/zip, 4 datasets
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...