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Evolutionary model for glacial lake-outburst fans at the ice-sheet front: Development of meltwater outlets and origins of bedforms
(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
(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
(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
(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
(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
(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
(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 ... -
Investigating limitations of RAMMS:Debrisflow as a slushflow simulation tool: Using numerical modelling as a tool to predict slushflow runouts
(Master thesis; Mastergradsoppgave, 2024-05-30)Slushflows are defined as rapid mass movement and occur when water-saturated snow (slush), rapidly moves downslope as a flowlike process. The high-water content of the flow results in high density and mobility flow that poses a significant danger to everything in its path. To predict how slushflows navigates the terrain, numerical modelling is a valuable tool. The output of the simulations would ... -
Geomorphological study of unstable rock slope deformation on Stáluvárri, Kåfjorden, Troms
(Mastergradsoppgave; Master thesis, 2024-05-15)Unstable rock slope failures are catastrophic hazards with a long history in Norway. A large portion of these have been detected within Troms County, with a high percentage of them the Lyngenfjorden fault zone. Stáluvárri, a mountain in Kåfjord commune, is such a slope with detected bodies undergoing slow displacement rates. Bedrock compositions on the slope has abundant mica schists, with a thrust ... -
The origin and evolution of LCT pegmatites in Helgeland, northern Norway: stable isotope evidence from tourmaline (δ11B) and garnet (δ18O, ∆’17O)
(Master thesis; Mastergradsoppgave, 2024-06-07)The processes leading to formation of rare-element enriched granitic pegmatites are controversially debated amongst petrologists and economic geologists. Two contrasting genetic models discuss the necessity of a parental granitic pluton as the magma source versus an anatectic origin via partial melting of metasedimentary rocks. Geochemical tools such as the analysis of stable isotopic compositions ... -
Fluid Flow and seafloor gas seepage studies of Tampen Spurr
(Mastergradsoppgave; Master thesis, 2024-05-16)The southern areas of the North Sea are shallow waters with a depth of roughly 50m, which includes the German section, Dutch section, Danish and the UK sector of the North Sea. The north of the North Sea is much deeper but generally less than 200m, except within the Norwegian Trough/Trench towards the northeast, the only region of deep waters. Significant oil and gas discoveries have been made within ... -
Methanotroph activity and connectivity between two seep systems north off Svalbard
(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 ... -
Snowdrift Analysis using FlowCapt FC4 and LiDAR Data at Fv. 53 Tyin-Årdal
(Mastergradsoppgave; Master thesis, 2024-05-15)The wind is essential in distribution of snow and the degree of avalanche danger. There are a lot of uncertainties regarding quantification of wind-transported snow, which is of importance for local avalanche warning and Remote Avalanche Control Systems (RACS) - which is conducted by Skred AS along Fv. 53 (County Road 53) Tyin-Årdal. A snowdrift sensor, FlowCapt 4 (FC4), is installed along this ... -
Characteristics and failure mechanisms of the Sieidi unstable rock slope
(Mastergradsoppgave; Master thesis, 2024-05-14)Seidi is an unstable rock slope at the western end of the Sørfjord in Tromsø municipality, Troms County, northern Norway. It displays clear signs of rock slope deformation: an offset at the crest, multiple scarps, talus and loose material and a bulging slope. The objective of this work is to interrogate the failure mechanics in order to determine the degree of control lithology and bedrock structure ... -
A distinctive rare earth element signature for pyrite oxidation and glacial weathering
(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 ... -
Dating and analysis of the Hinlopen Megaslide, northern Svalbard
(Mastergradsoppgave; Master thesis, 2024-05-15)During a research cruise in the summer of 2022, a number of sediment cores were collected from the main headwall scar area of the Hinlopen Megaslide, northern Svalbard. In this study two of those sediment cores have undergone 14C AMS radiocarbon dating and a multi-proxy analysis to determine an accurate age for the slide deposits in this location. The results have been calibrated using the ... -
Marine- and Lacustrine Deposition of Eskers
(Mastergradsoppgave; Master thesis, 2024-05-16)The future stability of modern marine-terminating ice sheets is of great concern as an increased rate of retreat might mark the onset of their collapse. An increased rate of retreat is accompanied by an increase in meltwater and sediment discharge at the ice margin which has prompted research to focus on the drainage system of marine-terminating ice sheets. Recent discoveries of eskers at water-terminating ... -
A sedimentary insight into the coastal and environmental evolution of Hollendarbukta, Isfjorden: Early Holocene to present
(Mastergradsoppgave; Master thesis, 2024-05-13)Dramatic physical and biological shifts are occurring in the Arctic in response to rising surface air temperatures. Sedimentary coastal environments are particularly sensitive to these changes as they form at the interface between the terrestrial and shallow marine realm. The need to investigate sedimentary archives from coastal environments is crucial, to understand how they have responded during ... -
Contrasting Methane Seepage Dynamics in the Hola Trough Offshore Norway: Insights From Two Different Summers
(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
(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.
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