Now showing items 418-437 of 989

    • Impact of tides and sea-level on deep-sea Arctic methane emissions 

      Sultan, Nabil; Plaza-Faverola, Andreia; Vadakkepuliyambatta, Sunil; Buenz, Stefan; Knies, Jochen (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-09)
      Sub-sea Arctic methane and gas hydrate reservoirs are expected to be severely impacted by ocean temperature increase and sea-level rise. Our understanding of the gas emission phenomenon in the Arctic is however partial, especially in deep environments where the access is difficult and hydro-acoustic surveys are sporadic. Here, we report on the first continuous pore-pressure and temperature measurements ...
    • Impact of Timanian thrust systems on the late Neoproterozoic–Phanerozoic tectonic evolution of the Barents Sea and Svalbard 

      Koehl, Jean-Baptiste Philippe; Magee, Craig; Anell, Ingrid (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-12)
      The Svalbard Archipelago consists of three basement terranes that record a complex Neoproterozoic– Phanerozoic tectonic history, including four contractional events (Grenvillian, Caledonian, Ellesmerian, and Eurekan) and two episodes of collapse- to rift-related extension (Devonian–Carboniferous and late Cenozoic). Previous studies suggest that these three terranes likely accreted during the early ...
    • Impact of Timanian thrusts on the Phanerozoic tectonic history of Svalbard 

      Koehl, Jean-Baptiste P. (Conference object; Konferansebidrag, 2019-09-13)
      Despite more than a century of investigation, the relationship between basement rocks throughout the Svalbard Archipelago is still a mystery. Though these rocks display similar geochronological ages, they show significantly different metamorphic grades and structures. Thus far, Svalbard was believed to be composed of three terranes of rocks formed hundreds–thousands of kilometers apart and accreted ...
    • Implications of transient methane flux on associated biological communities in high-arctic seep habitats, Storbanken, Norwegian Barents sea 

      Heyl, Taylor P.; Panieri, Giuliana; Fornari, Daniel J.; Mattingsdal, Rune; Sauer, Simone; Yao, Haoyi; McCartin, Luke; McElwee, Elisabeth; Shank, Timothy M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-09-21)
      The continental margins of the Arctic Ocean basin contain methane seeps, where transient fluxes of seafloor methane are released due to the thermal dissociation of gas hydrates. An increase in shallow methane seeps identified over the past decade, potentially due to enhanced warming of the Arctic Ocean bottom water and associated destabilization of hydrate structure. Biological communities associated ...
    • In Situ Temperature Measurements at the Svalbard Continental Margin: Implications for Gas Hydrate Dynamics 

      Riedel, M.; Wallmann, K.; Berndt, C; Pape, T.; Freudenthal, T.; Bergenthal, M.; Bünz, Stefan; Bohrmann, G. (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-30)
      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) ...
    • The influence of a model subglacial lake on ice dynamics and internal layering 

      Gudlaugsson, Eythor; Humbert, Angelika; Kleiner, Thomas; Kohler, Jack; Andreassen, Karin (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-04-05)
      As ice flows over a subglacial lake, the drop in bed resistance leads to an increase in ice velocities and a draw down of isochrones and cold ice. The ice surface flattens as it adjusts to the lack of resisting forces at the base. The rapid transition in velocity induces changes in ice viscosity and releases deformation energy that can raise the temperature locally. Recent studies of Antarctic ...
    • Influence of a rigid backstop on the flow pattern during thrusting of the supracrustal Balsfjord Series of the North Norwegian Caledonides 

      Höpfl, Stephan Maximilian; Konopásek, Jiří; Sláma, Jiří (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-17)
      The Caledonian evolution of the low–medium grade Balsfjord Series (Troms, Northern Norway) is characterized by four sets of deformation structures that developed progressively during burial and exhumation from underneath the high-grade Nakkedal and Tromsø nappe complexes. The Balsfjord Series commonly displays top-to-the SSE–SE directed movement during the development of the main metamorphic fabric ...
    • The influence of Coriolis force driven water circulation on the palaeoenvironment of Hornsund (S Spitsbergen) over the last century 

      Pawłowska, Joanna; Zajączkowski, Marek; Szczuciński, Witold; Zaborska, Agata; Kucharska, Małgorzata; Jernas, Patrycja Ewa; Forwick, Matthias (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-22)
      The influence of the Coriolis force on the Hornsund fjord environment (southern Spitsbergen) was investigated in the marine sedimentary record from the last century. Due to the influence of the rotational effects, Atlantic and Arctic Water enter the fjord along the southern shore and exit along the northern shore. Thus, the sedimentary record from the southern part reflects the large‐scale hydrological ...
    • Influence of methane seepage on isotopic signatures in living deep-sea benthic foraminifera, 79° N 

      Melaniuk, Katarzyna; Sztybor, Kamila; Treude, Tina; Sommer, Stefan; Rasmussen, Tine Lander (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-21)
      Fossil benthic foraminifera are used to trace past methane release linked to climate change. However, it is still debated whether isotopic signatures of living foraminifera from methane-charged sediments refect incorporation of methane-derived carbon. A deeper understanding of isotopic signatures of living benthic foraminifera from methane-rich environments will help to improve reconstructions of ...
    • The inheritance of a Mesozoic landscape in western Scandinavia 

      Fredin, Ola; Viola, Giulio; Zwingmann, Horst; Sørlie, Ronald; Brönner, Marco; Lie, Jan-Erik; Grandal, Else Margrethe; Müller, Axel Bernd; Margreth, Annina; Vogt, Christoph; Knies, Jochen (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-28)
      In-situ weathered bedrock, saprolite, is locally found in Scandinavia, where it is commonly thought to represent pre-Pleistocene weathering possibly associated with landscape formation. The age of weathering, however, remains loosely constrained, which has an impact on existing geological and landscape evolution models and morphotectonic correlations. Here we provide new geochronological evidence ...
    • Innovative methods to monitor rock and mountain slope deformation 

      Hormes, Anne; Adams, Marc; Amabile, Anna Sara; Blauensteiner, Franz; Demmler, Christian; Fey, Christine; Ostermann, Marc; Rechberger, Christina; Sausgruber, Thomas; Vecchiotti, Filippo; Vick, Louise Mary; Zangerl, Christian (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-02-17)
      Displacement rates of mountain slope deformations that can affect entire valley mountain flanks are often measured spatially distributed in‐situ without spatial significance. The spatially explicit measurement and recording of time series of slope deformations is a challenge, as the unstable slopes are often disintegrated into several subdomains, which move with different deformation rates. The ...
    • Insights into glacial processes from micromorphology of silt-sized sediment 

      Lepp, Allison P.; Miller, Lauren E.; Anderson, John B.; O’Regan, Matt; Winsborrow, Monica Caroline Mackay; Smith, James A.; Hillenbrand, Claus-Dieter; Wellner, Julia S.; Prothro, Lindsay O.; Podolskiy, Evgeny A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-07)
      Silt-rich meltwater plume deposits (MPDs) analyzed from marine sediment cores have elucidated relationships that are clearly connected, yet difficult to constrain, between subglacial hydrology, ice-marginal landforms, and grounding-zone retreat patterns for several glacial catchments. Few attempts have been made to infer details of subglacial hydrology, such as flow regime, geometry of drainage ...
    • Insights into the REY inventory of seep carbonates from the Northern Norwegian margin using geochemical screening 

      Schier, Katharina; Himmler, Tobias; Lepland, Aivo; Kraemer, Dennis; Schönenberger, Jasmin; Bau, Michael (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-27)
      Rare earth element and yttrium (REY) systematics of authigenic seep carbonates can provide insights into the physico-chemical characteristics of seep systems and allow discrimination of carbonate precipitation under seawater- or porewater-dominated fluid regimes. However, care must be taken when interpreting their REY systematics, since seep carbonates comprise a mixture of detrital silicates and ...
    • Integrated characterization of igneous intrusions in Central Spitsbergen 

      Festøy, Marte Hergot (Master thesis; Mastergradsoppgave, 2017-05-15)
      Igneous intrusions have a strong influence on petroleum systems, groundwater aquifers, and CO2 storage reservoirs, particularly because they can act as either barriers to, or carriers for fluid flow. This depends on several syn- and post emplacement processes, including fracture development in the intrusion and the host rocks, contact metamorphism of the host rocks, and hydrothermal activity. ...
    • Integrated characterization of the Upper Permian Kapp Starostin Formation in central Spitsbergen, Svalbard. From outcrop to geomodel. 

      Larssen, Kristine (Master thesis; Mastergradsoppgave, 2018-05-14)
      Natural fractures significantly contribute to improved reservoir quality and recovery factor, especially in carbonate reservoirs. It is important to characterize the matrix and fracture properties, as well as their interaction, in order to describe the natural fracture system and improve the understanding of its effects on a reservoir. This study integrates multi-scale outcrop data from central ...
    • Integrated Petrophysical and Seismic interpretation of Norne Field, Norway. 

      Khan, Adnan (Master thesis; Mastergradsoppgave, 2014-09-16)
      The aim of this thesis is to evaluate petrophysical properties and seismic interpretation of main reservoirs of Norne field in Mid Norwegian sea. Petrophysical evaluation helps in getting familiar with reservoir characterization using wireline logs data. The main concentration has been given to evaluate different reservoir properties i.e. porosity, shale volume, water saturation, hydrocarbon saturation, ...
    • An integrated view of the methane system in the pockmarks at Vestnesa Ridge, 79°N 

      Panieri, Giuliana; Bünz, Stefan; Fornari, Daniel J.; Escartin, Javier; Serov, Pavel; Jansson, Pär; Torres, Marta E.; Hong, Wei-Li; Sauer, Simone; Garcia, Rafael; Gracias, Nuno (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-08)
      The Vestnesa Ridge is a NW-SE trending, ~ 100 km-long, 1–2 km-thick contourite sediment section located in the Arctic Ocean, west of Svalbard, at 79°N. Pockmarks align along the ridge summit at water depths of ~ 1200 m; they are ~ 700 m in diameter and ~ 10 m deep relative to the surrounding seafloor. Observations of methane seepage in this area have been reported since 2008. Here we summarize and ...
    • An Integrative Taxonomic Survey of Benthic Foraminiferal Species (Protista, Rhizaria) from the Eastern Clarion-Clipperton Zone 

      Himmighofen, Oceanne E.; Holzmann, Maria; Barrenechea Angeles, Inés; Pawlowski, Jan; Gooday, Andrew J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-24)
      The abyssal Pacific Clarion Clipperton Zone (CCZ) hosts vast, commercially valuable seafloor deposits of polymetallic nodules. Foraminifera (testate protists) dominate benthic communities in this region. Here, we present a taxonomic survey, combining morphological and genetic data and focussing on mainly meiofauna-sized Foraminifera from the eastern CCZ. Sequences obtained from >100 specimens, the ...
    • Interaction between ice streaming, glacitectonics and fluid flow in Håkjerringdjupet, SW Barents Sea 

      Jakobsen, Frank Werner (Master thesis; Mastergradsoppgave, 2016-05-13)
      By using high resolution multibeam swath batymetry and 2- and 3D seismic data this thesis investigate the interactions between ice streaming, glacitectonics and fluid flow in Håkjerringdjupet. The source area for a glacitectonic hill-hole pair is located directly above spatial fluid accumulations assosiated to a fault complex. Glacitectonic deposits are found directly downstream from this area. We ...
    • Interaction of submarine tailings with natural sediments in three northern Norwegian coastal areas. Sedimentological, mineralogical and geochemical constraints 

      Figenschau, Nikolai (Master thesis; Mastergradsoppgave, 2018-05-15)
      Submarine tailings placements (STPs) is an alternative practice of handling mine waste, which involves deposition of tailings into submarine environments. However, the environmental impacts of STPs remain poorly understood. This thesis is a contribution to improve the understanding of how submarine tailings placements interact with natural sediments. It is based on multi-proxy analyses of 10 sediment ...