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  • Quaternary interaction of cryospheric and oceanographic processes along the central-east Greenland margin 

    Perez, Lara F.; Nielsen, Tove; Rasmussen, Tine Lander; Winsborrow, Monica (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-08-16)
    The east Greenland margin has been influenced by oceanographic and cryospheric processes since the late Miocene, when the southwards flow of the East Greenland Current (EGC) initiated and ice sheets first advanced across the margin. However, the relative importance of these processes, and their influence on the sedimentation of the margin through time remains poorly understood. High‐resolution ...
  • Modelling persistent methane seepage offshore western Svalbard since early Pleistocene 

    Knies, Jochen; Daszinnies, Matthias Christian; Plaza-Faverola, Andreia; Chand, Shyam; Sylta, Øyvind; Bünz, Stefan; Johnson, Joel E; Mattingsdal, Rune; Mienert, Jurgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-31)
    Recent observations of extensive methane release into the oceans and atmosphere have raised concern as to whether rising temperatures across the Arctic could drive rapid destabilization of gas hydrate reservoirs. Here, we report modelling results from hydrate-modulated methane seepage from Vestnesa Ridge, offshore western Svalbard, suggesting that continuous leakage has occurred from the seafloor ...
  • An assessment of biomarker-based multivariate classification methods versus the PIP25 index for paleo Arctic sea ice reconstruction 

    Koseoglu, Denizcan; Belt, Simon T.; Husum, Katrine; Knies, Jochen (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-08-30)
    The development of various combinative methods for Arctic sea ice reconstruction using the sympagic highly-branched isoprenoid (HBI) IP<sub>25</sub> in conjunction with pelagic biomarkers has often facilitated more detailed descriptions of sea ice conditions than using IP<sub>25</sub> alone. Here, we investigated the application of the Phytoplankton-IP<sub>25</sub> index (PIP<sub>25</sub>) and a ...
  • Early and Middle Pleistocene environments, landforms and sediments in Scotland 

    Hall, Adrian M.; Merritt, Jon W.; Connell, E. Rodger; Hubbard, Alun Lloyd (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-10-04)
    This paper reviews the changing environments, developing landforms and terrestrial stratigraphy during the Early and Middle Pleistocene stages in Scotland. Cold stages after 2.7 Ma brought mountain ice caps and lowland permafrost, but larger ice sheets were short-lived. The late Early and Middle Pleistocene sedimentary record found offshore indicates more than 10 advances of ice sheets from ...
  • Quantification of the magnitude of net erosion in the southwest Barents Sea using sonic velocities and compaction trends in shales and sandstones 

    Ktenas, Dimitrios; Henriksen, Erik; Meisingset, Ivar; Nielsen, Jesper Kresten; Andreassen, Karin (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-09-19)
    During specific intervals within Mesozoic and Cenozoic times, several areas of the southwestern Barents Sea were subjected to uplift and erosion. Areas with missing shallow stratigraphic interval sections and major erosion can be seen at several places along interpreted regional profiles in the southwestern Barents Sea. A new Normal Compaction Trend (NCT) for two selected shale– and ...
  • Atypical biological features of a new cold seep site on the LofotenVesterålen continental margin (northern Norway) 

    Sen, Arunima; Himmler, Tobias; Hong, Wei-Li; Chitkara, Cheshtaa; Lee, Raymond W.; Ferré, Benedicte; Lepland, Aivo; Knies, Jochen (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-02-11)
    A newly discovered cold seep from the Lofoten-Vesterålen margin (Norwegian Sea) is dominated by the chemosymbiotrophic siboglinid <i>Oligobrachia haakonmosbiensis</i> like other high latitude seeps, but additionally displays uncharacteristic features. Sulphidic bottom water likely prevents colonization by cnidarians and sponges, resulting in fewer taxa than deeper seeps in the region, representing ...
  • Monitoring Of CO2 Leakage Using High-Resolution 3D Seismic Data – Examples From Snøhvit, Vestnesa Ridge And The Western Barents Sea 

    Bellwald, Benjamin; Waage, Malin; Planke, S; Lebedeva-Ivanova, Nina; Polteau, S; Tasianas, Alexandros; Bünz, Stefan; Plaza-Faverola, Andreia; Berndt, Christian; Stokke, H.H.; Millett, John; Myklebust, R. (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-11-21)
    Injection of CO2 in subsurface reservoirs may cause overburden deformation and CO2 leakage. The aim of this study is to apply technologies for detection and monitoring of CO2 leakage and deformation above the injection reservoirs. The examples of this study include data from the Vestnesa Ridge natural seep site, the Snøhvit gas field and CO2 storage site region, and the Gemini North gas reservoir. ...
  • Syn-kinematic hydration reactions, grain size reduction, and dissolution-precipitation creep in experimentally deformed plagioclase-pyroxene mixtures 

    Marti, Sina; Stunitz, Holger; Heilbronner, Renée; Plümper, Oliver; Kilian, Rüdiger (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-08-09)
    It is widely observed that mafic rocks are able to accommodate high strains by viscous flow. Yet, a number of questions concerning the exact nature of the involved deformation mechanisms continue to be debated. In this contribution, rock deformation experiments on four different water-added plagioclase–pyroxene mixtures are presented:(i) plagioclase(An60–70)–clinopyroxene–orthopyroxene,(ii) ...
  • Characterization of Carbonate Crust from a Recently Discovered Methane Seep on the North Atlantic Continental Margin of the USA 

    Gabitov, Rinat; Borrelli, Chiara; Buettner, Jacob; Kirkland, Brenda; Skarke, Adam; Trail, Dustin; Garner, Brittany; Testa, Maurice; Wahidi, Mahnaz; Hoff, Christopher; Khasanov, Salavat; Panieri, Giuliana; Thirumalai, Roobanvenkatesh; Thomas, Jay; Weremeichik, Jeremy; Zverkova, Irina (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-02-26)
    This study is focused on mineralogical and chemical characterization of an authigenic carbonate rock (crust) collected at a recently discovered cold seep on the US North Atlantic continental margin. X-ray diffraction (XRD) and scanning electron microscopy (SEM) indicate that the carbonate rock is composed of microcrystalline aragonite cement, white acicular aragonite crystals (AcAr), equant quartz ...
  • Widespread and accelerating glacier retreat on the Lyngen Peninsula, northern Norway, since their 'Little Ice Age' maximum 

    Stokes, Chris R.; Andreassen, Liss Marie; Champion, Matthew R; Corner, Geoffrey D. (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-06)
    The recession of mountain glaciers worldwide is increasing global sea level and, in many regions, human activities will have to adapt to changes in surface hydrology. Thus, it is important to provide up-to-date analyses of glacier change and the factors modulating their response to climate warming. Here we report changes in the extent of >120 glaciers on the Lyngen Peninsula, northern Norway, where ...
  • Correlation between tectonic stress regimes and methane seepage on the western Svalbard margin 

    Plaza-Faverola, Andreia; Keiding, Marie (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-01-15)
    Methane seepage occurs across the western Svalbard margin at water depths ranging from < 300 m, landward from the shelf break, to > 1000 m in regions just a few kilometres from the mid-ocean ridges in the Fram Strait. The mechanisms controlling seepage remain elusive. The Vestnesa sedimentary ridge, located on oceanic crust at a depth of 1000–1700 m, hosts a perennial gas hydrate and associated free ...
  • Two-billion-year-old evaporites capture Earth’s great oxidation 

    Blättler, C.L.; Claire, M.W.; Prave, A.R.; Kirsimäe, K.; Higgins, J.A.; Medvedev, P.V.; Romashkin, A.E; Rychanchik, D.V.; Zerkle, A.L.; Paiste, Kärt; Kreitsmann, T.; Millar, I.L.; Hayles, J.A.; Bao, H.; Turchyn, A.V.; Warke, M.R.; Lepland, Aivo (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-04-20)
    Major changes in atmospheric and ocean chemistry occurred in the Paleoproterozoic era (2.5 to 1.6 billion years ago). Increasing oxidation dramatically changed Earth’s surface, but few quantitative constraints exist on this important transition. This study describes the sedimentology, mineralogy, and geochemistry of a 2-billion-year-old, ~800-meter-thick evaporite succession from the Onega Basin in ...
  • Physical Conditions of Fast Glacier Flow: 3.Seasonally-Evolving Ice Deformation onStore Glacier, West Greenland 

    Young, Tun Jan; Christoffersen, Poul; Doyle, Samuel H.; Nicholls, Keith W.; Stewart, C.L.; Hubbard, Bryn; Hubbard, Alun Lloyd; Lok, Lai B.; Brennan, Paul V.; Benn, Douglas I; Luckman, Adrian; Bougamont, Marion H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-01-08)
    Temporal variations in ice sheet flow directly impact the internal structure within ice sheetsthrough englacial deformation. Large-scale changes in the vertical stratigraphy within ice sheets havebeen previously conducted on centennial to millennial timescales; however, intra-annual changes inthe morphology of internal layers have yet to be explored. Over a period of 2 years, we use autonomousphas ...
  • Impact of Arctic shelf summer stratification on Holocene climate variability 

    Thibodeau, Benoit; Bauch, Henning A.; Knies, Jochen (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-05-21)
    Understanding the dynamic of freshwater and sea-ice export from the Arctic is crucial to better comprehend the potential near-future climate change consequences. Here, we report nitrogen isotope data of a core from the Laptev Sea to shed light on the impact of the Holocene Siberian transgression on the summer stratification of the Laptev Sea. Our data suggest that the oceanographic setting was ...
  • High-resolution landform assemblage along a buried glacio-erosive surface in the SW Barents Sea revealed by P-Cable 3D seismic data 

    Bellwald, Benjamin; Planke, Sverre; Lebedeva-Ivanova, Nina; Piasecka, Emilia Daria; Andreassen, Karin (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-02-01)
    The Quaternary sedimentary record in the Arctic captures a diverse and evolving range of landscapes reflecting cli-mate changes. Here we study the geological landform assemblage of the Upper Regional Unconformity (URU) in theSW Barents Sea. The aims are (i) to characterize buried geological landforms on a meter-scale resolution, (ii) to un-derstand their link with underlying structures, and (iii) ...
  • Deglacial dynamics of the Vestfjorden - Trænadjupet palaeo-ice stream, northern Norway 

    Laberg, Jan Sverre; Eilertsen, Raymond S; Salomonsen, Gaute R. (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-05-18)
    Few well‐dated records of the deglacial dynamics of the large palaeo‐ice streams of the major Northern Hemisphere ice sheets are presently available, a prerequisite for an improved understanding of the ice‐sheet response to the climate warming of this period. Here we present a transect of gravity‐core samples through Trænadjupet and Vestfjorden, northern Norway, the location of the Trænadjupet – ...
  • Reply to 'Challenges with dating weathering products to unravel ancient landscapes' 

    Fredin, Ola; Viola, Giulio; Zwingmann, Horst; Sørlie, Ronald; Brönner, Marco; Lie, Jan-Erik; Grandal, Else Margrethe; Müller, Axel; Margreth, Annina; Vogt, Christoph; Knies, Jochen (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-15)
    <i>Introduction</i>: As the title of the correspondence by Fossen et al.1 suggests, determining the age of landscape elements of the Earth surface is difficult. We thus welcome the opportunity to clarify our arguments on the contentious themes touched upon by Fredin et al.2 The age of landscapes has been a recurring research topic for the last century. Often, landscape ages can be deduced indirectly ...
  • Submarine geomorphology at the front of the retreating hansbreen tidewater glacier, hornsund fjord, southwest spitsbergen 

    Cwiakala, Joanna; Moskalik, Mateusz; Forwick, Matthias; Wojtysiak, Kacper; Gizejewski, Jerzy; Szczucinski, Witold (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-01)
    A 1:10,000 scale bathymetric map as well as 1:20,000 scale backscattering and geomorphological maps of two bays Isbjørnhamna and Hansbukta in the Hornsund fjord (Spitsbergen) present the submarine relief that was primarily formed during and after the retreat of the Hansbreen tidewater glacier. Geomorphological mapping was performed using multibeam bathymetric data and seismoacoustic profiling. The ...
  • Depositional processes on the distal Scoresby Trough Mouth Fan (ODP Site 987): Implications for the Pleistocene evolution of the Scoresby Sund Sector of the Greenland Ice Sheet 

    Laberg, Jan Sverre; Rydningen, Tom Arne; Forwick, Matthias; Husum, Katrine (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-11-28)
    The investigation of trough mouth fans (TMFs), important paleoclimatic archives on mid- and high-latitude continental margins, has so far mainly been based on the integration of various types of acoustic data supplemented with short sediments cores. In consequence, sedimentological and chronological data about parts of TMFs deposited prior to the Last Glacial Maximum remains sparse. Here, we re-evaluate ...
  • Repeatability of high-resolution 3D seismic data 

    Waage, Malin; Bünz, Stefan; Landrø, Martin; Plaza-Faverola, Andreia; Waghorn, Kate Alyse (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-12-21)
    High-resolution 4D (HR4D) seismic data have the potential for improving the current state-of-the-art in detecting shallow (≤500−1000  m below seafloor) subsurface changes on a very fine scale (approximately 3–6 m). Time-lapse seismic investigations commonly use conventional broadband seismic data, considered low to moderate resolution in our context. We have developed the first comprehensive time ...

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