Viser treff 779-798 av 985

    • Salt movements in three provinces in the southwestern Barents Sea: development, timing, and implications of regional structural differences 

      Thorsen, Truls (Master thesis; Mastergradsoppgave, 2019-05-15)
      This study has investigated salt movements in the Nordkapp Basin, on the Loppa High (Svalis Dome) and on the Bjarmeland Platform (Samson- and Norvarg domes). The aim is to discuss how differences in salt growth potentially relates to the structural evolution of - and differences between - these three provinces. Evaluation of seismic 2D- and 3D data together with well correlation, allowed a regional ...
    • Salt-driven evolution of a gas hydrate reservoir in Green Canyon, Gulf of Mexico 

      Portnov, Aleksei D; Cook, Ann E.; Heidari, Mahdi; Sawyer, Derek E.; Nikolinakou, Maria (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09)
      The base of the gas hydrate stability zone (GHSZ) is a critical interface, providing a first-order estimate of gas hydrate distribution. Sensitivity to thermobaric conditions makes its prediction challenging particularly in the regions with dynamic pressure-temperature regime. In Green Canyon in the northern Gulf of Mexico (Block GC955), the seismically inferred base of the GHSZ is 450 meters (1476 ...
    • Sammenhengen mellom landskap og tektonikk på Moskenesøya og Flakstadøya, Lofoten. 

      Trulssen, Mads Fremming (Master thesis; Mastergradsoppgave, 2008-12-04)
      Lofoten utgjør en opphevet horst i forhold til omkringliggende bassenger og består hovedsakelig av prekambrisk grunnfjell. Tidligere modeller viser at landområdene og sokkelområdene utenfor Lofoten ser ut til å ha hatt en lik ekstensjonshistorie med flere faser av forkastningsbevegelser, innsynkning og oppheving gjennom mesozoikum og kenozoikum. Steile strukturer i berggrunnen danner svakhetssoner ...
    • Sand waves and sediment transport on the SW Barents sea continental slope 

      Waage, Malin (Master thesis; Mastergradsoppgave, 2012-11-15)
      I study a sand-wave field in ~600 meters water depth on the continental slope offshore Northern Norway. Using multibeam bathymetry data from 2008 and 2011 and P-Cable high-resolution 3D seismic data from 2011, I characterize the field. Sand waves reach up to 6.6 m in height and have wavelengths as large as 140 m. They are mostly asymmetric in shape with the steepest side dipping to the northwest, ...
    • Sea ice and millennial-scale climate variability in the Nordic seas 90 kyr ago to present 

      Hoff, Ulrike; Rasmussen, Tine Lander; Stein, Ruediger; Ezat, Mohamed; Fahl, Kirsten (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-07-26)
      In the light of rapidly diminishing sea ice cover in the Arctic during the present atmospheric warming, it is imperative to study the distribution of sea ice in the past in relation to rapid climate change. Here we focus on glacial millennial-scale climatic events (Dansgaard/Oeschger events) using the sea ice proxy IP25 in combination with phytoplankton proxy data and quantification of diatom species ...
    • Sea ice and primary production proxies in surface sediments from a High Arctic Greenland fjord: Spatial distribution and implications for palaeoenvironmental studies 

      Ribeiro, Sofia; Sejr, Mikael K.; Limoges, Audrey; Heikkilä, Maija; Andersen, Thorbjørn Joest; Tallberg, Petra; Weckström, Kaarina; Husum, Katrine; Forwick, Matthias; Dalsgaard, Tage; Massé, Guillaume; Seidenkrantz, Marit-Solveig; Rysgaard, Søren (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-01-23)
      In order to establish a baseline for proxy-based reconstructions for the Young Sound–Tyrolerfjord system (Northeast Greenland), we analysed the spatial distribution of primary production and sea ice proxies in surface sediments from the fjord, against monitoring data from the Greenland Ecosystem Monitoring Programme. Clear spatial gradients in organic carbon and biogenic silica contents reflected ...
    • Sea ice thickness from air-coupled flexural waves 

      Romeyn, Rowan; Hanssen, Alfred; Ruud, Bent Ole; Johansen, Tor Arne (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-06-28)
      Air-coupled flexural waves (ACFWs) appear as wave trains of constant frequency that arrive in advance of the direct air wave from an impulsive source travelling over a floating ice sheet. The frequency of these waves varies with the flexural stiffness of the ice sheet, which is controlled by a combination of thickness and elastic properties. We develop a theoretical framework to understand these ...
    • Sea ice-ocean coupling during Heinrich Stadials in the Atlantic–Arctic gateway 

      el Bani Altuna, Naima; Mohamed, Mohamed Mahmoud Ezat Ahmed; Smik, Lukas; Muschitiello, Francesco; Belt, Simon T.; Knies, Jochen Manfred; Rasmussen, Tine Lander (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-01-11)
      The variability of Arctic sea-ice during abrupt stadial-interstadial shifts in the last glacial period remain poorly understood. Here, we investigated the millennial-scale relationship, with a focus on Heinrich Stadials (HS), between sea-ice cover and bottom water temperature (BWT) during Marine Isotope Stages (MIS) 3 and 2 (64–13 ka) in the Fram Strait using new molecular sea ice biomarker data and ...
    • Sea-ice dynamics in an Arctic coastal polynya during the past 6500 years 

      Knies, Jochen; Pathirana, Irene Dorothea; Cabedo-Sanz, Patricia; Banica, Ana; Fabian, Karl; Rasmussen, Tine Lander; Forwick, Matthias; Belt, Simon T. (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-12-23)
      The production of high-salinity brines during sea-ice freezing in circum-arctic coastal polynyas is thought to be part of northern deep water formation as it supplies additional dense waters to the Atlantic meridional overturning circulation system. To better predict the effect of possible future summer ice-free conditions in the Arctic Ocean on global climate, it is important to improve our ...
    • Seabed morphology and sedimentary processes on high-gradient trough mouth fans offshore Troms, northern Norway 

      Rydningen, Tom Arne; Laberg, Jan Sverre; Kolstad, Vidar (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-01)
      Trough mouth fans (TMF) situated at the mouths of formerly glaciated cross-shelf troughs are important paleoclimatic archives. Whereas the sedimentary processes of large, low-gradient TMFs have received considerable interest, little attention has been paid to the other end member of this landform class, i.e. TMFs with higher slope gradients. Detailed swath-bathymetric data and seismic profiles from ...
    • Seal characterization and integrity in uplifted basins: Insights from the northern Barents Shelf 

      Paulsen, Renate Strugstad; Birchall, Thomas; Senger, Kim; Grundvåg, Sten-Andreas (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-02-16)
      Seal integrity is a key property for petroleum exploration. This is even more the case in uplifted basins, as exemplified by the northern Barents Shelf. Uplift may lead to fracturing, decompaction, gas expansion and fluid flow. Therefore, it is critical to understand the mechanical behaviour of the Jurassic shale caprocks in the Greater Hoop area, where hydrocarbon accumulations are situated as ...
    • Seal integrity in the uplifted basins in the greater Hoop area on the Northern Barents Shelf 

      Paulsen, Renate Strugstad; Grundvåg, Sten-Andreas; Senger, Kim; Stueland, Eirik (Conference object; Konferansebidrag, 2019)
      The geological evolution of the northern Barents Shelf is complex, and the area has undergone several phases of tectonic activity leading to a mosaic of several deep and shallow basins, platforms, salt-cored domes and structural highs. The area is highly gas prone with some very few commercial oil discoveries, and only two fields currently in production. Deep burial and subsequent Late Cretaceous–Cenozoic ...
    • Seasonal sea ice persisted through the Holocene Thermal Maximum at 80°N 

      Pieńkowski, Anna J.; Husum, Katrine; Belt, Simon T.; Ninnemann, Ulysses S; Köseoğlu, Denizcan; Divine, Dmitry V.; Smik, Lukas; Knies, Jochen; Hogan, Kelly; Noormets, Riko (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-06-15)
      The cryospheric response to climatic warming responsible for recent Arctic sea ice decline can be elucidated using marine geological archives which offer an important long-term perspective. The Holocene Thermal Maximum, between 10 and 6 thousand years ago, provides an opportunity to investigate sea ice during a warmer-than-present interval. Here we use organic biomarkers and benthic foraminiferal ...
    • Seasonal shifts of microbial methane oxidation in Arctic shelf waters above gas seeps 

      Gründger, Friederike; Probandt, David; Knittel, Katrin; Carrier, Vincent; Kalenitchenko, Dimitri; Silyakova, Anna; Serov, Pavel; Ferré, Benedicte; Svenning, Mette Marianne; Niemann, Helge (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-07)
      The Arctic Ocean subseabed holds vast reservoirs of the potent greenhouse gas methane (CH<sub>4</sub>), often seeping into the ocean water column. In a continuously warming ocean as a result of climate change an increase of CH<sub>4</sub> seepage from the seabed is hypothesized. Today, CH<sub>4</sub> is largely retained in the water column due to the activity of methane-oxidizing bacteria (MOB) that ...
    • Sediment source-to-sink analysis in the Norwegian Arctic 

      Lasabuda, Amando P. E. (Conference object; Konferansebidrag, 2022)
    • Sediment transport on the Palos Verdes shelf, California 

      Ferré, Benedicte; Sherwood, Christopher R.; Wiberg, Patricia L. (Journal article; Tidsskriftartikkel; Peer reviewed, 2010-02-01)
      Sediment transport and the potential for erosion or deposition have been investigated on the Palos Verdes (PV) and San Pedro shelves in southern California to help assess the fate of an effluent-affected deposit contaminated with DDT and PCBs. Bottom boundary layer measurements at two 60-m sites in spring 2004 were used to set model parameters and evaluate a one-dimensional (vertical) model of local, ...
    • Sedimentary ancient DNA from Lake Skartjørna, Svalbard: Assessing the resilience of arctic flora to Holocene climate change 

      Alsos, Inger Greve; Sjögren, Per Johan E.; Edwards, Mary E.; Landvik, Jon Y.; Gielly, Ludovic; Forwick, Matthias; Coissac, Eric; Brown, Antony G; Jakobsen, Leif Vidar; Merkel, Marie Kristine Føreid; Pedersen, Mikkel Winter (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-11)
    • Sedimentary ancient DNA: a new paleogenomic tool for reconstructing the history of marine ecosystems 

      Nguyen, Ngoc-Loi; Devendra, Dhanushka; Szymanska, Natalia; Greco, Mattia; Barrenechea Angeles, Inés Andrea; Weiner, Agnes K. M.; Ray, Jessica Louise; Cordier, Tristan; De Schepper, Stijn; Pawłowski, Jan; Pawłowska, Joanna (Journal article; Tidsskriftartikkel, 2023-06-09)
      Sedimentary ancient DNA (sedaDNA) offers a novel retrospective approach to reconstructing the history of marine ecosystems over geological timescales. Until now, the biological proxies used to reconstruct paleoceanographic and paleoecological conditions were limited to organisms whose remains are preserved in the fossil record. The development of ancient DNA analysis techniques substantially expands ...
    • Sedimentary environment and seismic anomalies of the upper Brygge and Kai formations on the northern part of the Mid-Norwegian Continental Shelf 

      Krokmyrdal, Suchada Yaiying (Master thesis; Mastergradsoppgave, 2017-05-15)
      The sedimentary environment and seismic anomalies of the upper Brygge and Kai formations on the northern part of the Mid-Norwegian Continental Shelf is analysed from 3D seismic data and the exploration well 6604/2-1. This was done in order to give a better understanding of the paleo-climatic development in the period before the establishment of the large-scale ice sheets of the Northern Hemisphere, ...
    • Sedimentary processes and depositional environment of the distal part of the Bear Island Trough Mouth Fan, SW Barents Sea reconstructed from a giant piston core 

      Dahl, Nora (Master thesis; Mastergradsoppgave, 2016-05-15)
      Multi-proxy analyses of the giant piston core MD992301 (including lithostratigraphy, physical properties and XRF-scanning) and analyses of swath bathymetry data was integrated in order to reconstruct the glacial history and paleoenvironment of the distal parts of the INBIS channel, located between the distal Bear Island Trough Mouth Fan and Storfjorden Trough Mouth Fan. Based on the swath bathymetry ...