Viser treff 1-20 av 740

    • Glacial erosion and quaternary landscape development of the Eurasian Arctic 

      Patton, Henry Jared; Alexandropoulou, Nikolitsa; Lasabuda, Amando P. E.; Knies, Jochen Manfred; Andreassen, Karin Marie; Winsborrow, Monica Caroline Mackay; Laberg, Jan Sverre; Hubbard, Alun Lloyd (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-09-19)
      Multiple ice age cycles spanning the last three million years have fundamentally transformed the Arctic landscape. The cadence, intensity and pattern of this glacial modification underpin the stability of Arctic geosystems over geologic time scales, including its hydrology, circulation patterns, slope stability, hydrocarbon fluid flow, geochemical/sediment cycling and nutrient supply. The Barents ...
    • Mechanical Impact of Heterogeneously Distributed H2O on Quartz Deformation 

      Pongrac, Petar; Jeřábek, Petr; Stunitz, Holger; Raimbourg, Hugues; Racek, Martin; Jollands, Michael C.; Gies, Nils; Lueder, Mona; Lexa, Ondrej; Nègre, Lucille (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-31)
      In order to identify relations between mechanical behavior, deformation mechanisms, microstructural properties, and H<sub>2</sub>O distribution, Tana‐quartzite samples with added H<sub>2</sub>O ranging from 0 to 0.5 wt.% were deformed by axial shortening at constant displacement rates, at 900°C and 1 GPa, reaching up to ∼30% bulk strain. Samples with lower quantities of added H<sub>2</sub>O (0.1 ...
    • Deep learning models for regional phase detection on seismic stations in Northern Europe and the European Arctic 

      Myklebust, Erik B.; Köhler, Andreas (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-23)
      Seismic phase detection and classification using deep learning is so far poorly investigated for regional events since most studies focus on local events and short time windows as the input to the detection models. To evaluate deep learning on regional seismic records, we create a data set of events in Northern Europe and the European Arctic. This data set consists of about 151 000 three component ...
    • Weichselian–Holocene glacial history of the Sjuøyane archipelago, northern Svalbard 

      Schomacker, Anders; Alexanderson, Helena; Farnsworth, Wesley Randall; Furze, Mark F.A.; Kjellman, Sofia Elisabeth; Kirchner, Nina; Erstorp, Elias Strandell; Noormets, Riko; Jomelli, Vincent; Ingólfsson, Ólafur (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-05)
      The Sjuøyane archipelago is the northernmost land area of Svalbard; thus, it provides a window to study the terrestrial glacial history and dynamics of the Svalbard–Barents Sea Ice Sheet and complement marine geological studies in the region. To reconstruct the glacial history of Sjuøyane, we describe coastal sedimentary sections in Quaternary sediments and constrain their chronology by radiocarbon ...
    • Evolutionary model for glacial lake-outburst fans at the ice-sheet front: Development of meltwater outlets and origins of bedforms 

      Weckwerth, Piotr; Kalińska, Edyta; Wysota, Wojciech; Krawiec, Arkadiusz; Alexanderson, Helena; Chabowski, Marek (Journal article; Tidsskriftartikkel, 2024-03-08)
      <p>Large-scale landforms originated from jökulhlaups or glacial lake-outburst floods (GLOFs), and their small-scale components help in recognising the sedimentary environment of the flood. The GLOF fans that developed along the Pleistocene ice-sheet margin have not been investigated in detail, and north-eastern Poland, with its Megaflood Landform System and Bachanowo and Szeszupka fans, seems ideal ...
    • Arctic Freshwater Sources and Ocean Mixing Relationships Revealed With Seawater Isotopic Tracing 

      Kopec, Ben G.; Klein, Eric S.; Feldman, Gene C.; Pedron, Shawn A.; Bailey, Hannah; Causey, Douglas; Hubbard, Alun Lloyd; Marttila, Hannu; Welker, Jeffrey M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-29)
      The Arctic Ocean and adjacent seas are undergoing increased freshwater influx due to enhanced glacial and sea ice melt, precipitation, and runoff. Accurate delineation of these freshwater sources is vital as they critically modulate ocean composition and circulation with widespread and varied impacts. Despite this, the delineation of freshwater sources using physical oceanographic measurements (e.g., ...
    • Tidal and seasonal influence on cold seep activity and methanotroph efficiency in the North Sea 

      de Groot, Tim R.; Menoud, Malika; van Bleijswijk, Judith; Niemann, Helge (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-12)
      The ocean’s methane emission to the atmosphere is dominated by continental shelves where cold seeps are globally common features. Seeps emit methane into the hydrosphere, but temporal variations and controls of seep activity and the efficiency of the microbial methane filter in the water column are scarce. Here we address these knowledge gaps by measuring whole water column methane inventories and ...
    • Unravelling controls on multi-source-to-sink systems: A stratigraphic forward model of the early–middle Cenozoic of the SW Barents Sea 

      Lasabuda, Amando; Chiarella, Domenico; Sømme, Tor Oftedal; Grundvåg, Sten-Andreas; Dore, Anthony G.; Primadani, Grandika; Rydningen, Tom Arne; Laberg, Jan Sverre; Hansen, Alfred (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-10)
      Source-to-sink dynamics are subjected to complex interactions between erosion, sediment transfer and deposition, particularly in an evolving tectonic and climatic setting. Here we use stratigraphic forward modelling (SFM) to predict the basin-fill architecture of a multi-source-to-sink system based on a state-of-the-art numerical approach. The modelling processes consider key source-to-sink parameters ...
    • Glacial troughs as centres of organic carbon accumulation on the Norwegian continental margin 

      Diesing, Markus; Paradis, Sarah; Jensen, Henning; Thorsnes, Terje; Bjarnadóttir, Lilja Rún; Knies, Jochen Manfred (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-15)
      The role of continental margin sediments in the carbon cycle and the associated management potential for climate mitigation are currently poorly understood. Previous work has indicated that margin sediments store significant amounts of organic carbon, but few studies have quantified the rates at which organic carbon is accumulated. Here, we use machine learning to make spatial predictions of the ...
    • Geological and glaciological controls of 21,700 active methane seeps in the northern Norwegian Barents sea 

      Serov, Pavel; Andreassen, Karin Marie; Winsborrow, Monica Caroline Mackay; Mattingsdal, Rune; Patton, Henry Jared (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-11)
      Due to tectonic uplift in the Cenozoic and numerous shelf-wide glaciations during the Quaternary, ∼1–2.5 km of sedimentary overburden has been eroded from the Barents Sea shelf, leading to the exhumation and partial uncapping of hydrocarbon accumulations. Widespread natural gas and oil leakage from the glacially eroded middle-upper Triassic reservoir directly into the water column has been documented ...
    • Near-surface characterization using shear-wave resonances: A case study from offshore Svalbard, Norway 

      Taweesintananon, Kittinat; Rørstadbotnen, Robin Andre; Landrø, Martin; Johansen, Ståle Emil; Arntsen, Børge; Forwick, Matthias; Hansen, Alfred (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-14)
      Shear-wave (S-wave) resonances are typically observed when the surficial marine sediments over a rock substrate have relatively low S-wave velocities. We observe these phenomena using ocean-bottom fiber-optic distributed acoustic sensing (DAS) in two subsea fiber-optic telecommunication cables in Svalbard, Norway. Strong seismic energy from sufficiently large earthquakes is required to trigger and ...
    • Methanotroph activity and connectivity between two seep systems north off Svalbard 

      de Groot, Tim; Kalenitchenko, Dimitri Stanislas Desire; Moser, Manuel; Argentino, Claudio; Panieri, Giuliana; Dølven, Knut Ola; Ferré, Benedicte; Svenning, Mette Marianne; Niemann, Helge (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-14)
      Understanding methane flux dynamics in Arctic cold seep systems and the influence of oceanic currents on microbial methane-oxidizing bacteria (MOB) is crucial for assessing their impact on Arctic methane emissions. Here, we investigate methane dynamics and associated microbial communities at two cold seep areas, Norskebanken and Hinlopen Trough, North of Svalbard. Methane concentrations and methane ...
    • A distinctive rare earth element signature for pyrite oxidation and glacial weathering 

      Jang, Kwangchul; Bayon, Germain; Pourret, Olivier; Joe, Young Jin; Kim, Jung-Hyun; Byun, Eunji; Forwick, Matthias; León, Rafael; Nam, Seung-Il (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-15)
      The application of rare earth elements (REE) and neodymium (Nd) isotopes to authigenic Fe-(oxyhydr)oxide phases leached from marine sediments can be used for reconstructing past ocean circulation and chemical weathering patterns on nearby continental landmasses. To explore the behaviour of REE during chemical weathering in glacial environments, we analyzed the authigenic fraction of glacimarine ...
    • Contrasting Methane Seepage Dynamics in the Hola Trough Offshore Norway: Insights From Two Different Summers 

      Ferré, Benedicte; Barreyre, Thibaut; Bünz, Stefan; Argentino, Claudio; Corrales-Guerrero, Jorge; Dølven, Knut Ola; Stetzler, Marie Helene Paula; Fallati, Luca; Sert, Muhammed Fatih; Panieri, Giuliana; Rastrick, Samuel; Kutti, Tina; Moser, Manuel (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-09)
      This study investigates the temporal variations in methane concentration and flare activity in the Hola trough (offshore Norway) during May 2018 and June 2022. Between these time periods, methane seep activity exhibits 3.5 times increase, as evidenced by hydroacoustic measurements. As the seep area in the Hola trough is constantly within the hydrate stability zone, the observed increase cannot be ...
    • NordVulk 1974-2024 

      Schomacker, Anders; Sturkell, Erik; Keiding, Jakob Kløve (Journal article; Tidsskriftartikkel; Peer reviewed, 2024)
      Nordisk Vulkanologisk Institut, senere kendt som Nordisk Vulkanologisk Center (NordVulk), på Island fylder 50 år i 2024. Desværre sammenfalder den runde fødselsdag med, at NordVulk nedlægges. Dermed afsluttes en lang, fremgangsrig og succesfuld æra med nordisk vulkanologisk forskning på Island. Her beretter vi lidt om NordVulks liv.
    • Seasonal precipitation variability on Svalbard inferred from Holocene sedimentary leaf wax δ2H 

      Kjellman, Sofia Elisabeth; Thomas, Elizabeth K.; Farnsworth, Wesley R.; Cowling, Owen C.; Allaart, Lis; Brynjólfsson, Skafti; Schomacker, Anders (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-26)
      Svalbard spans large climate gradients, associated with atmospheric circulation patterns and variations in ocean heat content and sea ice cover. Future precipitation increases are projected to peak in the northeast and to mainly occur in winter, but uncertainties underscore the need for reconstructions of long-term spatial and temporal variations in precipitation amounts and seasonality. We use lipid ...
    • Early aerial expedition photos reveal 85 years of glacier growth and stability in East Antarctica 

      Dømgaard, Mads; Schomacker, Anders; Isaksson, Elisabeth; Millan, Romain; Huiban, Flora; Dehecq, Amaury; Fleischer, Amanda; Moholdt, Geir; Andersen, Jonas K.; Bjørk, Anders A. (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-25)
      During the last few decades, several sectors in Antarctica have transitioned from glacial mass balance equilibrium to mass loss. In order to determine if recent trends exceed the scale of natural variability, long-term observations are vital. Here we explore the earliest, large-scale, aerial image archive of Antarctica to provide a unique record of 21 outlet glaciers along the coastline of East ...
    • The Ocean Senses Activity Book: Enriching Ocean Literacy through a multisensory approach 

      Panieri, Giuliana; Sancak Sert, Zeynep; Maric, Filip; Poto, Margherita Paola; Murray, Emily Margaret (Chapter; Bokkapittel, 2024-05-23)
      This chapter outlines the development of “The Ocean Senses Activity Book” integrating a multisensory approach to ocean education for pupils and the general public. Originating from an expedition in the Arctic Ocean, the project aimed to cultivate more effective cognitive approaches to ocean literacy education and communication. It bridged the gap between scientific exploration and public engagement, ...
    • The Agenda 2030 and the Imperative for Research and Education for the Climate and the Oceans 

      Panieri, Giuliana; Poto, Margherita Paola; Murray, Emily Margaret (Chapter; Bokkapittel, 2024-05-23)
      This chapter sets the scene and provides background information regarding the primary objective of the book: to contribute to the knowledge base for climate education and research, with a specific focus on the oceans and water. Within this framework, the chapter situates educational and research strategies that specifically focus on ocean literacy, developed and coordinated by the authors over the ...
    • Connecting with The Deep: Lifelong Learning (LLL) and Marine Sustainability 

      Johansen, Caroline; Williams, Rhianon; Xylouri, Ourania; Panieri, Giuliana (Chapter; Bokkapittel, 2024-05-23)
      This chapter frames marine sustainability within ongoing global and regional initiatives in lifelong learning and adult education. The authors of this chapter argue that to achieve the ambitious targets set out in the SDGs, our adult population must be able to recognise, engage with, and act upon economic, social, and environmental challenges. The authors of this chapter present the many barriers ...