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    • 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 ...
    • Quantifying short-term changes in snow strength due to increasing liquid water content above hydraulic barriers 

      Schlumpf, Mikael; Hendrikx, Jordy; Stormont, John C.; Webb, Ryan (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-31)
      The rapid weakening of snow layers that accumulate infiltrating liquid water is a well-known, but poorly quantified, mechanism for wet-snow slab avalanche formation. Therefore, quantifying this mechanical process is a crucial part of forecasting these snow avalanches accurately. Currently, studies do not agree on how snow strength should change as a function of volumetric liquid water content ( ) ...
    • Quantitative interpretation using inverse rock-physics modeling on AVO data 

      Jensen, Erling Hugo; Johansen, Tor Arne; Avseth, Per Åge; Bredesen, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-16)
      Quantitative seismic interpretation has become an important and critical technology for improved hydrocarbon exploration and production. However, this is typically a resource-demanding process that requires information from several well logs, building a representative velocity model, and, of course, high-quality seismic data. Therefore, it is very challenging to perform in an exploration or appraisal ...
    • Quartz rheology constrained from constant-load experiments: Consequences for the strength of the continental crust 

      Ghosh, Subhajit; Stunitz, Holger; Raimbourg, Hugues; Précigout, Jacques (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-21)
      The mechanical properties of quartz are fundamental to control the plastic behaviour of the continental crust. Our understanding of quartz rheology is still limited in the following respects: i) the large variability of flow law parameters in the earlier literature (stress exponent n = 4 to ≤ 2 and activation energy Q = 120 to 242 kJ/mol), and ii) the difficulty to identify the rate-limiting deformation ...
    • Quartz textural analysis from an anastomosing shear zone system: Implications for the tectonic evolution of the Ribeira belt, Brazil 

      Conte, Thailli; Cavalcante, Carolina; Lagoeiro, Leonardo Evangelista; Fossen, Haakon; Silveira, C.S. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-18)
      Strain localization and influence of grain-size reduction processes were investigated from field and microstructural observations, and from quartz textural analysis using EBSD, in rocks deformed along an anastomosing network of shear zones in the Ribeira belt in Brazil. Rocks deformed along the Lancinha shear zone (LSZ) display high percentage of recrystallized grains, in which quartz recrystallized ...
    • Quaternary and Neogene Reservoirs of the Norwegian Continental Shelf and the Faroe-Shetland Basin 

      Bellwald, Benjamin; Planke, Sverre; Vadakkepuliyambatta, Sunil; Buenz, Stefan; Batchelor, Christine L.; Manton, Ben; Zastrozhnov, Dmitry; Walker, Faye; Myklebust, Reidun (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-06-01)
      Glaciogenic reservoirs host important hydrocarbon resources across the globe. Examples such as the Peon and Aviat discoveries in the North Sea show that Quaternary and Neogene reservoirs can be prospective in the region. In this study, we interpret 2D and 3D reflection seismic data combined with borehole information to document unconventional play models from the shallow subsurface of the Norwegian ...
    • 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 ...
    • Rapid Atlantification along the Fram Strait at the beginning of the 20th century 

      Tesi, Tommaso; Muschitiello, Francesco; Mollenhauer, Gesine; Miserocchi, Stefano; Langone, Leonardo; Ceccarelli, Chiara; Panieri, Giuliana; Chiggiato, Jacopo; Nogarotto, Alessio; Hefter, Jens; Ingrosso, Gianmarco; Giglio, Federico; Giordano, Patrizia; Capotondi, Lucilla (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-11-24)
      The recent expansion of Atlantic waters into the Arctic Ocean represents undisputable evidence of the rapid changes occurring in this region. Understanding the past variability of this “Atlantification” is thus crucial in providing a longer perspective on the modern Arctic changes. Here, we reconstruct the history of Atlantification along the eastern Fram Strait during the past 800 years using ...
    • Rapid post-glacial bedrock weathering in coastal Norway 

      Andersen, Jane Lund; Margreth, Annina; Fredin, Ola; Linge, Henriette; Goodfellow, Bradley W.; Faust, Johan Christoph; Knies, Jochen; Solbakk, Terje; Brook, Edward J.; Scheiber, Thomas; van der Lelij, Roelant; Burki, Valentin Josef; Rubensdotter, Brita Lena Eleonor Fredin; Himmler, Tobias; Yesilyurt, Serdar; Christl, Marcus; Vockenhuber, Christof; Akcar, Naki (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-26)
      Quantifying bedrock weathering rates under diverse climate conditions is essential to understanding timescales of landscape evolution. Yet, weathering rates are often difficult to constrain, and associating a weathered landform to a specific formative environment can be complicated by overprinting of successive processes and temporally varying climate. In this study, we investigate three sites ...
    • Rapid Surface Lowering of Benito Glacier, Northern Patagonian Icefield 

      Ryan, Jonathan C.; Sessions, Martin; Wilson, Ryan; Wündrich, Olaf; Hubbard, Alun L. (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-05-01)
      The Patagonian Icefields, which straddle the Andes below 46°S, are two of the most sensitive ice masses on Earth to climate change. However, recent mass loss from the icefields along with its spatial and temporal variability is not well-constrained. Here we determine surface elevation changes of Benito Glacier, a 163 km2 outlet glacier draining the western flank of the North Patagonian Icefield, ...
    • The Raunis section, central Latvia, revisited: first luminescence results and re-evaluation of a key Baltic States stratigraphic site 

      Kalińska, Edyta; Alexanderson, Helena; Krievāns, Māris (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-08)
      In interstadial deposits, sand interbeds gain limited consideration in comparison with organic sediments, and therefore tend to be underrepresented in paleoenvironmental reconstructions. The Raunis site, central-eastern Latvia, is an example where organic beds have already gained some attention and been used to understand the complex interactions between advance and retreat of the Scandinavian Ice ...
    • Re-evaluation and extension of the Marine Isotope Stage 5 tephrostratigraphy of the Faroe Islands region: The cryptotephra record 

      Abbott, Peter M.; Austin, William E.N.; Davies, Siwan M.; Pearce, Nicholas John Geoffrey; Rasmussen, Tine Lander; Wastegård, Stefan; Brendryen, Jo (Journal article; Tidsskriftartikkel; Peer reviewed, 2014)
    • Recent acceleration of a rock glacier complex, Ádjet, Norway, documented by 62 years of remote sensing observations 

      Eriksen, Harald Øverli; Rouyet, Line; Lauknes, Tom Rune; Berthling, Ivar; Hindberg, Heidi; Larsen, Yngvar; Corner, Geoffrey D. (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-08-23)
      Recent acceleration of rock glaciers is well recognized in the European Alps, but similar behavior is hardly documented elsewhere. Also, the controlling factors are not fully understood. Here we provide evidence for acceleration of a rock glacier complex in northern Norway, from 62 years of remote sensing data. Average annual horizontal velocity measured by aerial feature tracking increased from ...
    • Reconstructing the retreat dynamics of the Bjørnøyrenna Ice Stream based on new 3D seismic data from the central Barents Sea 

      Piasecka, Emilia Daria; Winsborrow, Monica; Andreassen, Karin; Stokes, Chris R. (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-11-01)
      The stability of contemporary ice sheets is influenced by the discharge from ice streams - corridors of fast-flowing ice bounded by ice flowing an order of magnitude slower. Reconstructions of palaeo-ice stream dynamics contribute to our understanding of ice stream sensitivity to the ocean-climate system and can aid in the numerical modelling and prediction of future changes in contemporary ice ...
    • Reconstruction of a volcano-sedimentary environment shared by the Porongos and Várzea do Capivarita complexes at 790 Ma, Dom Feliciano Belt, southern Brazil 

      Battisti, Matheus Ariel; Bitencourt, Maria de Fatima; Schmitt, Renata da Silva; Nardi, Lauro Valentim Stoll; Martil, Mariana Maturano Dias; De Toni, Giuseppe Betino; Pimentel, Márcio Martins; Armstrong, Richard; Konopásek, Jiří (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-06-22)
      This work investigates the pre-collisional (before ca. 650 Ma) history of the Dom Feliciano Belt in southernmost Brazil through geochronological and zircon oxygen isotope study. U–Pb SHRIMP dating of two orthogneiss samples from the Várzea do Capivarita Complex and one metarhyolite sample from the Porongos Complex yielded crystallisation ages of 786 ± 5 Ma, 780 ± 10 Ma and 787 ± 5 Ma, respectively. ...
    • Reconstruction of Atlantic Water variability during the Holocene in the western Barents Sea 

      Groot, Diane; Sørensen, Steffen Aagaard; Husum, Katrine (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-01-10)
      The gravity core JM09-KA11-GC from 345m water depth on the western Barents Sea margin was investigated for down-core distribution patterns of benthic Foraminifera, stable isotopes, and sedimentological parameters in order to reconstruct the flow of Atlantic water during the Holocene. The core site is located below the Atlantic water masses flowing into the Arctic Ocean and close to the Arctic front. ...
    • Reconstruction of hydrographic changes in the southern Norwegian Sea during the past 135 kyr and the impact of different foraminiferal Mg/Ca cleaning protocols 

      Ezat, Mohamed; Rasmussen, Tine Lander; Groeneveld, Jeroen (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-20)
      The shallow subsurface hydrography in the southern Norwegian Sea during the past 135,000 years was investigated using parallel measurements of Mg/Ca and δ18O in shells of the planktic foraminiferal species Neogloboquadrina pachyderma. Two cleaning methods were applied prior to Mg/Ca analysis, “Mg cleaning” and “full cleaning” methods. Different results were obtained, which are most likely due to a ...
    • Reconstruction of ice sheet retreat after the Last Glacial maximum in Storfjorden, southern Svalbard 

      Nielsen, Tove; Rasmussen, Tine Lander (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-12-15)
      Storfjorden is a large north-south trending sound located in the southern part of Svalbard in the northwestern Barents Sea. Presently, several glaciers drain into the northern and western part of Storfjorden. Our study area covers the southern part of the sound, which is divided by a north-south striking basement ridge (the ‘Mid-ridge’) into a narrow western trough (‘Little-Storfjorden’) and a broader ...
    • Reconstruction of the Virtual Geomagnetic Pole (VGP) path at high latitude for the last 22 kyr: The role of radial field flux patches as VGP attractor 

      Caricchi, Chiara; Campuzano, Saioa A.; Sagnotti, Leonardo; Macri, Patrizia; Lucchi, Renata Giulia (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-08-24)
      Reconstruction of geomagnetic field changes has a strong potential to complement geodynamo modeling and improve the understanding of Earth's core dynamics. Recent works based on geomagnetic measurements pointed out that over the last two decades the position of the north magnetic pole has been largely determined by the influence of two competing flux lobes under Canada and Siberia. In order to ...
    • Redox fluctuations, trace metal enrichment and phosphogenesis in the ~2.0 Ga Zaonega Formation 

      Kipp, Michael A.; Lepland, Aivo; Buick, Roger (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-24)
      The ~2.0 Ga Zaonega Formation (ZF) holds one of the oldest phosphorites in the geologic record, reaching >15% P<sub>2</sub>O<sub>5</sub>. Understanding the depositional conditions that enabled sedimentary phosphorus enrichment in this unit will thus help us to interpret the significance of the temporal distribution of phosphorites in Earth’s early history. Here we use an array of major and trace ...