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Now showing items 466-485 of 989
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The last two millennia: climate, ocean circulation and paleoproductivity inferred from planktic foraminifera, south-western Svalbard margin
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-20)We reconstruct climate and changes in water-mass properties in relation to variations in palaeoproductivity at the south-western Svalbard margin throughout the last 2000 years. Environmental conditions in subsurface (ca. 250–75 m) and near-surface to surface water (75–0 m) were studied on the basis of the distribution patterns and fluxes of planktic foraminiferal faunas. Stable isotopes in three ... -
Late Cenozoic development of the continental margin off Lofoten-Vesterålen and Troms
(Conference object; Konferansebidrag, 2011) -
Late Cenozoic development of the mid-Norwegian continental margin – a study of the Naust Formation based on 3D-seismic data
(Master thesis; Mastergradsoppgave, 2020-06-15)The late Cenozoic evolution of the outer continental shelf and slope on the northern part of the mid-Norwegian margin is studied using 3D seismic data. The late Cenozoic stratigraphy is subdivided into four main seismic units: unit A (oldest) to D and correlated to the established stratigraphic framework of the Naust Formation, where the oldest unit in this study correlates to the upper part of Naust ... -
Late Cenozoic erosion estimates for the northern Barents Sea: Quantifying glacial sediment input to the Arctic Ocean
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-11-14)A compilation of seismic data has been used to characterize the Neogene – Quaternary sedimentary succession of the northwestern Barents Sea continental margin to better understand the paleoenvironmental evolution and the sedimentary processes involved. The Neogene strata are dominated by contourites related to the ocean circulation established from the opening of the Fram Strait connecting the ... -
Late Cenozoic erosion in the SW Barents Sea, and its influence on salt movement
(Master thesis; Mastergradsoppgave, 2019-05-15)The late Cenozoic evolution of the southwestern Barents Sea shelf includes periods of uplift, erosion and glaciations. This part of the stratigraphy has been studied using 2D and 3D seismic data, with emphasis on the interplay between uplift, erosion and glaciations and salt movement. The study area comprises the Svalis, Samson and Norvarg domes and the Nordkapp Basin, where halokinesis has been a ... -
Late Cenozoic paleoenvironment and erosion estimates for the NE Svalbard continental margin – preliminary results
(Conference object; Konferansebidrag, 2017) -
Late Cenozoic paleoenvironments in the Veslemøy High area, SW Barents Sea based on 3D- and 2D- seismic data
(Master thesis; Mastergradsoppgave, 2009-05)The aim of this master thesis has been to interpret the Late Cenozoic paleo-environments and the sedimentary processes in the Veslemøy High area, southwestern Barents Sea. Six seismic units and eight seismic unconformities, including the seafloor, are identified in the study area and correlated with previous work in the Sørvestnaget Basin. Submarine channels with a downslope (E-W) orientation suggest ... -
Late Devonian–Carboniferous faulting and controlling structures and fabrics in NW Finnmark
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-09-10)In the SW Barents Sea, Devonian–Carboniferous collapse led to the formation of major basins and faults, e.g., the Hammerfest Basin bounded by the Troms–Finnmark Fault Complex, and rhomboid- to sigma-shaped (half-)grabens on the Finnmark Platform. High-resolution aeromagnetic and bathymetry data from the shallow shelf show that analogue fault systems are present in coastal and onshore areas of NW ... -
A Late Glacial–Early Holocene multiproxy record from the eastern Fram Strait, Polar North Atlantic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014) -
Late Holocene pteropod distribution across the base of the south-eastern Mediterranean margin: the importance of the > 63 µm fraction
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-03-17)Euthecosomata pteropods were analysed in core sediments collected in the framework of the 2016 EUROFLEETS2 SEMSEEP cruise, offshore of Israel, in the eastern Mediterranean Sea. The investigated cores were retrieved in a deep-sea coral area at 690 m depth, an actively methane-seeping pockmark area at 1038 m depth, and a deep-sea channel area at 1310 m water depth. We identified and documented the ... -
Late Miocene Ice Rafting in the Iceland Sea. Evidence from coarse fraction analysis of ODP Site 907
(Master thesis; Mastergradsoppgave, 2018-05-15)A high-resolution sedimentary record from ODP Leg 151 Hole 907A has been investigated with sedimentological and geochemical methods to study the paleoenvironmental evolution of the Iceland Sea over a 1-Myr time interval in the Late Miocene. Climate deterioration characterizes the Neogene period, culminating in a transition to bipolar glaciations in the Late Pliocene (Thiede and Myhre, 1996). Ice ... -
Late Paleoproterozoic and Mesoproterozoic magmatism of the Nico Pérez Terrane (Uruguay): Tightening up correlations in southwestern Gondwana
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-04-04)New geochronological, isotopic and geochemical data were obtained from the late Paleoproterozoic and Mesoproterozoic magmatic units of the Nico Pérez Terrane (Uruguay). A U-Pb LA-ICP-MS zircon age of 1768 ± 11 Ma confirms the Statherian age for the Illescas rapakivi intrusion, being thus comparable with the age of the Campanero Unit felsic orthogneisses. Though both the Illescas and Campanero ... -
The Late Paleozoic development of the Ottar basin from seismic 3D interpretation
(Master thesis; Mastergradsoppgave, 2018-05-15)The Late Paleozoic sedimentary environments of the Ottar basin in the SW Barents Sea was studied using five 3D seismic surveys. By the use of seismic stratigraphic analysis and correlation to wells located in close proximity to the study area, the Paleozoic succession has been subdivided into 4 main units: Billefjorden Group (Late Devonian – Mid Carboniferous), Gipsdalen Group (Mid Carboniferous – ... -
Late Paleozoic-Cenozoic fault correlation and characterization of fault rocks in western Troms, North Norway
(Master thesis; Mastergradsoppgave, 2013-05-29)The present work focuses on the mapping and description of onshore brittle fault zones on the SW Barents Sea Margin, within gneisses and granitic intrusions belonging to the West Troms Basement Complex. The description of the brittle structures includes the geometry, kinematics and fault rock characteristics, using DEM satellite imaging, structural field work and a microstructural analysis of the ... -
Late Pliocene–early Pleistocene deep-sea basin sedimentation at high-latitudes: mega-scale submarine slides of the north-western Barents Sea margin prior to the shelf-edge glaciations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-01)At high‐latitude continental margins, large‐scale submarine sliding has been an important process for deep‐sea sediment transfer during glacial and interglacial periods. Little is, however, known about the importance of this process prior to the arrival of the ice sheet on the continental shelf. Based on new two‐dimensional seismic data from the NW Barents Sea continental margin, this study documents ... -
Late Quaternary depositional and glacial history of the Arliss Plateau off the East Siberian margin in the western Arctic Ocean
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-12-19)Sedimentary stratigraphy and facies analysis along with seismostratigraphic and multibeam bathymetrydata are used to reconstruct the last glacial impact on the Arliss Plateau (AP) and attendant sedimen-tation in the adjacent Chukchi Basin (CB) in the western Arctic Ocean off the East Siberian margin.Sediment core ARA02B/16B-GC from the AP lower slope captures glacier-related depositional historyduring ... -
Late Quaternary glacier and sea-ice history of northern Wijdefjorden, Svalbard
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-10)The deglaciation history and Holocene environmental evolution of northern Wijdefjorden, Svalbard, are reconstructed using sediment cores and acoustic data (multibeam swath bathymetry and sub‐bottom profiler data). Results reveal that the fjord mouth was deglaciated prior to 14.5±0.3 cal. ka BP and deglaciation occurred stepwise. Biomarker analyses show rapid variations in water temperature and sea ... -
Late Quaternary paleoceanography of Vestnesa Ridge, Fram Strait: Ostracode species as a potential indicator of cold seep activity
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-02)Past intensity of methane release from deep-ocean methane hydrates continues to be challenging to reconstruct reliably. Here, we used fossil ostracode fauna paired with foraminiferal δ<sup>13</sup>C values in a marine sediment core from Vestnesa Ridge, western Svalbard margin, to reconstruct methane seepage activity during the late Quaternary and to examine faunal response to deglacial climatic ... -
Late Quaternary tephra stratigraphy and paleoenvironmental reconstruction based on lake sediments from North and Northeast Iceland
(Mastergradsoppgave; Master thesis, 2020-07-12)Due to Iceland’s position in the middle of the North Atlantic, the island is highly sensitive to oceanic and atmospheric fluctuations, which lead to changes in the environment. These fluctuating environmental conditions in addition to Iceland’s high volcanic activity make it a strategic study area for paleoenvironmental and tephra studies. Lake sediments contain information about such past climate ... -
Late Quaternary terrigenous plant and coaly fragments found at Vestnesa Ridge, Fram Strait: implications for postglacial plant colonization at Svalbard
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-11-23)One of four marine cores of glacial sediments collected from a water depth of about 1200 m at Vestnesa Ridge (west of Svalbard) contained small fragments of coal, charcoal and moss. This material was restricted to a single level, and 14C dating of bivalves both above and below indicates an age of c. 18.0–15.5 kyr BP. Chemical analyses of the coal indicate that the provenance area was from the northern ...
