Now showing items 430-449 of 989

    • 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 ...
    • Interactions between deep formation fluid and gas hydrate dynamics inferred from pore fluid geochemistry at active pockmarks of the Vestnesa Ridge, west Svalbard margin 

      Hong, Wei-Li; Pape, T; Schmidt, C.; Yao, Haoyi; Wallmann, K.; Plaza-Faverola, Andreia; Rae, J.W.B; Lepland, Aivo; Bünz, Stefan; Bohrmann, G. (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-02-11)
      Seafloor seepage sites along the Vestnesa Ridge off west-Svalbard have been, for decades, a natural laboratory for the studies of fluid flow and gas hydrate dynamics at passive continental margins. The lack of ground truth evidence for fluid composition and gas hydrate abundance deep in the sediment sequence however prohibits us from further assessing the current model of pockmark evolution from the ...
    • Introduction to the volume, and definition and use of the term ‘tectono-sedimentary element’ 

      Drachev, Sergey; Brekke, Harald; Henriksen, Erik; Moore, Thomas (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-09-20)
      The present volume is rooted in a map of sedimentary successions of the Arctic Region by Grantz et al. (2011), and contains a brief, but comprehensive compilation of geological and geophysical data characterizing all significant sedimentary successions in the Arctic, which cover 57% of the polar area north of 64°N. Two main goals have been designated: (i) to provide, based on the present-day ...
    • Introduction: Processes and Palaeo-Environmental Changes in the Arctic from Past to Present (PalaeoArc) special issue 

      Lyså, Astrid; Jennings, Anne; Morigi, Caterina; Stokes, Chris R.; Winsborrow, Monica (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-01-05)
      PalaeoArc (Processes and Palaeo-Environmental Changes in the Arctic: From Past to Present) is an international network research programme, the aim of which is to understand and explain the climatically induced environmental changes in the Arctic that have taken place throughout the Quaternary and continue in the present-day (see http://www.palaeoarc.no/). This network builds on and extends the ...
    • Investigating the variability of Atlantic water inflow to the southwestern Barents Sea through Bjørnøyrenna during the Late Glacial and Holocene based on benthic foraminifera and sediment properties. 

      Tysnes, Anders (Master thesis; Mastergradsoppgave, 2017-05-15)
      This study is a part of the Barents Sea drill cuttings research initiative (BARCUT), investigating the inflow of Atlantic water to the southwestern Barents Sea during the Late Glacial and Holocene as well as providing data for future references.
    • An investigation into the causal factors of the Kråknes landslide 

      Sandnes, Torgrim (Mastergradsoppgave; Master thesis, 2021-05-15)
      On the 3rd of June 2020, a landslide measuring 600 meters long and 160 meters wide initiated along the shoreline at Kråknes, in Alta municipality in Troms and Finnmark County. The landslide was comprised of a series of smaller slides, which destroyed eight houses and a caravan in the process. Fortunately, no human lives were lost in the event. Due to the widespread presence of sensitive clays along ...
    • Ionospheric Response Observed by EISCAT During the 6–8 September 2017 Space Weather Event: Overview 

      Yamauchi, M; Sergiengko, Timothy; Enell, Carl-Fredrik; Schillings, A.; Slapak, R.; Johnsen, Magnar Gullikstad; Tjulin, A.; Nilsson, H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-09-03)
      We present ionospheric plasma conditions observed by the EISCAT radars in Tromsø and on Svalbard, covering 68°–81° geomagnetic latitude, during 6–8 September 2017. This is a period when X2.2 and X9.3 X‐ray flares occurred, two interplanetary coronal mass ejections (ICMEs) arrived at the Earth accompanied by enhancements of MeV‐range energetic particle flux in both the solar wind (SEP event) and inner ...
    • Iron cycling in Arctic methane seeps 

      Hong, Wei-Li; Latour, Pauline; Sauer, Simone; Sen, Arunima; Gilhooly, William P.; Lepland, Aivo; Fouskas, Fotios (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-26)
      Anoxic marine sediments contribute a significant amount of dissolved iron (Fe<sup>2+</sup>) to the ocean which is crucial for the global carbon cycle. Here, we investigate iron cycling in four Arctic cold seeps where sediments are anoxic and sulfidic due to the high rates of methane-fueled sulfate reduction. We estimated Fe<sup>2+</sup> diffusive fluxes towards the oxic sediment layer to be in the ...
    • Iron isotopes constrain sub-seafloor hydrothermal processes at the Trans-Atlantic Geotraverse (TAG) active sulfide mound 

      Sahlström, Fredrik; Troll, Valentin R; Strmic Palinkas, Sabina; Kooijman, Ellen; Zheng, Xinyuan (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-08-29)
      Sub-seafloor hydrothermal processes along volcanically active plate boundaries are integral to the formation of seafloor massive sulfide deposits and to oceanic iron cycling, yet the nature of their relationship is poorly understood. Here we apply iron isotope analysis to sulfide minerals from the Trans-Atlantic Geotraverse (TAG) mound and underlying stockwork, 26°N Mid-Atlantic Ridge, to trace ...
    • Is there a Climatic Control on Icelandic Volcanism? 

      Cooper, Claire L.; Savov, Ivan P.; Patton, Henry; Hubbard, Alun; Ivanovic, Ruza F.; Carrivick, Jonathan L.; Swindles, Graeme T. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-07)
      The evidence for periods of increased volcanic activity following deglaciation, such as following ice sheet retreat after the Last Glacial Maximum, has been examined in several formerly glaciated areas, including Iceland, Alaska, and the Andean Southern Volcanic Zone. Here we present new evidence supporting the theory that during episodes of cooling in the Holocene, Icelandic volcanic activity ...
    • Isstrømdynamikk og havbunnsgeomorfologi fra deglasiasjonen av det sørvestlige Barentshav, basert på 3D-, 2D-seismisk og batymetrisk data 

      Sommerseth, Audun Strand (Master thesis; Mastergradsoppgave, 2013-08-15)
      Batymetridata og 2D og 3D seismisk data og er brukt for å kartlegge formelementer i det sørvestlige Barentshavet. Megaskala glasiale lineasjoner (MSGL) kartlagt i de glasiale trauene indikerer tidligere isstrømaktivitet i Bjørnøyrenna og Djuprenna. Dynamiske endringer i strømningsretning er påvist fra MSGL med ulike orienteringer som kutter hverandre. Ut fra kartlagte MSGL er 10 strømningssett laget. ...
    • Jettan, Nordnesfjellet, Kåfjord, Troms – indre geometri og struktur, kinematikk og styrande faktorar av eit ustabilt fjellparti, basert på strukturellanalyse, geomorfologi og overvakingsdata 

      Skrede, Ingrid (Master thesis; Mastergradsoppgave, 2013-11-21)
      Det ustabile fjellpartiet, Jettan, har blitt studert med ei multidisiplinær tilnærming. Dette inkluderer strukturelle og geomorfologiske analyser i felt, studiar av sann-tid og periodisk overvaking og bruk av kart og digitale elevasjonsmodellar. Formålet har vore å avdekke indre struktur og geometri, kinematikken og kontrollerande faktorar for dei ustabile massane. Det ustabile fjellpartiet er ...
    • K-Ar illite and apatite fission track constraints onbrittle faulting and the evolution of the northern Norwegian passive margin 

      Davids, Corine; Wemmer, Klaus; Zwingmann, Horst; Kohlmann, Fabian; Jacobs, Joachim; Bergh, Steffen G (Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
      Determining the timing of post-Caledonian brittle faulting in northern Norway is important for the understanding of the extensional tectonic evolution of the north Norwegian continental margin. Fault gouges from the Troms and Vesterålen regions of northern Norway yield Carboniferous to Permian and Carboniferous to Cretaceous K–Ar illite ages, respectively. The results show a contrast in fault activity ...