Browsing by Title
-
Amundsen, Per-Arne; Gjelland, Karl Øystein; Knudsen, Rune; DalsbØ, laina h; Lien, Cesilie; Evjen, jan knut (Research report; Forskningsrapport, 2012)[+][-]
Abstract: Pasvikvassdraget har siden 1991 vært gjenstand for omfattende økologiske studier i regi av Ferskvannsøkologisk faggruppe ved Universitetet i Tromsø. Undersøkelsene har særlig vært rettet mot å undersøke effektene av at lagesilda, en fremmed fiskeart for Nord-Norge, kom inn i vassdraget på slutten av 1980-tallet. For å få en grundig forståelse av økologien i vassdraget har studiene også omfattet andre viktige fiskearter, krepsdyrplankton og bunndyr. Samtidig har vi hatt et nært samarbeid med russiske forskere angående tungmetallforurensing fra de russiske Nikel-smelteverkene, og med finske forskere gjennom sammenlignende studier med fiskebestandene i Enaresjøen og andre innsjøer i den finske delen av vassdraget. Totalt sett har dette resultert i mye ny og interessant kunnskap om Pasvikvassdraget; kunnskap som bl.a. er dokumentert gjennom 36 internasjonale publikasjoner, 22 fagrapporter og populærvitenskapelige publikasjoner, fire doktorgradsavhandlinger og 12 masteroppgaver (se Appendiks 2 for detaljer). I perioden 2008 – 2011 har langtidsstudiene i Pasvikvassdraget vært fulgt opp gjennom et prosjekt finansiert av Norges forskningsråd (Miljø-2015 programmet; prosjektnr. 183984/S30). Denne rapporten er en populærvitenskapelig sammenfatning av kunnskapen som har fremkommet gjennom dette prosjektet, der det særlig har vært lagt vekt på de langsiktige effektene av lagesildas invasjon og viktige forvaltningsmessige implikasjoner. URI: http://hdl.handle.net/10037/4417 File(s) in this item: 1
article.pdf (1.362Mb) -
Brattli, Tore (Journal article; Tidsskriftartikkel, Aug-1995)[+][-]
Abstract: Stadig flere biblioteksdatabaser blir nå tilgjengelige på World Wide Web med de mulighetene det gir til brukervennlig litteratursøking. En av disse nye mulig¬hetene er at de litteratursøkende nå kan lage sine egne brukervennlige og skreddersydde søkeskjermer, uten at de trenger å være dataeksperter. Det er i hovedsak to typer søkeskjermer som det åpner seg muligheter for. Den første er de tradisjonelle søkeskjermene med et eller flere felt som søket kan skrives inn i. Det er nå praktisk mulig å lage sine egne varianter av denne typen søkeskjermer, både når det gjelder hvilke felt som skal være med og hvilket søkespråk som skal benyttes. Den andre typen er lenking av søk til hypertekst, eller det som også kalles predefinerte søk. Dette åpner for spennende muligheter som f.eks. søking via emneordslister eller klassifikasjonstabeller, og bibliografier der hvert dokument er lenket til sin post i databasen. URI: http://hdl.handle.net/10037/1068 File(s) in this item: 1
article.pdf (173.0Kb) -
Bakstad, Knut (Master thesis; Mastergradsoppgave, 15-May-2010)[+][-]
Abstract: Masteroppgavens problemstilling og mål er å beskrive etablering, utvikling og forvaltning av landegrensen mellom Norge og Russland frem til 2010. Oppgaven er statsvitenskapelig og har brukt kvalitativ metode med litteraturstudier som utgangspunkt. Funnene viser det var en prosess over mange hundre år som gjorde at grensen ble liggende der den er i dag. I tillegg relateres utviklingen ift hendelser ellers i Europa, og empirien viser at utviklingen i stor grad er sammenfallende. Det er brukt nyere tilgjengelig russiske forfattere og historikere for å gi et bredere bilde for å forstå også denne tenkemåten omkring grensedannelse gjennom tidene. Etter andre verdenskrig ble det laget en ny overenskomst mellom de to land. Denne er meget detaljert og har blitt fulgt nøye, og dette er trolig en av årsakene til at grensen ikke er endret siden etableringen i 1826. Det har og er et betydelig skille ved denne grensen, tidligere skille mellom Warzawapakten og NATO, nå Schengen's yttergrense. De senere år har antall mannskaper blitt redusert ved grensen, men treningsnivå og materiell utvikling er forbedret på begge sider. Den norske regjerings nordområdestrategi benyttes aktivt, det er et tettere sammarbeid i regionen enn på lenge og arbeidet med grenseboerpass kan gjøre kulturelt og næringsmessig sammarbeid enda tettere i fremtiden. URI: http://hdl.handle.net/10037/2705 File(s) in this item: 1
thesis.pdf (4.090Mb) -
Streuff, Katharina Teresa (Master thesis; Mastergradsoppgave, 15-May-2013)[+][-]
Abstract: Swath bathymetry and chirp data have been used to investigate the submarine landform assemblages in inner Kongsfjorden, Svalbard, to reconstruct glacial dynamics during the Late Holocene. Multiple sets of landforms include two types of glacial lineations (groove-ridge features and small, drumlinoid ridges), terminal moraines and associated debris lobes, as well as small push moraines, and indicate repeated surge activity during the last 150 years for four of the five tidewater glaciers terminating in inner Kongsfjorden. Aside from confirming previously documented surges of Kronebreen in 1869, of Kongsvegen, in 1948, and of Blomstrandbreen in 1960, the local bathymetry also indicates a surge of Kongsbreen in 1897, a glacier that has so far been regarded as a non-surge type glacier. A conceptual model was developed to summarize the surge-induced landform assemblages in Kongsfjorden, and to compare them with other models from terrestrial and marine settings. Striking similarities exist between the Kongsfjorden model and landform assemblages documented for other Spitsbergen fjords. However, eskers and crevasse-fill ridges, the latter thought to be the only landform certainly indicative of glacier surges, lack in Kongsfjorden. Furthermore, the small, drumlinoid ridges inferred to be suggestive of the past ice flow direction in the study area seem to have more in common with glacial lineations generated by surging glaciers on land. The acoustic data was supplemented with two sediment cores from Kongsfjorden’s innermost basin. The reworked glacimarine deposits at the base of the more proximal core reflect proximal conditions, as they are part of a debris lobe that formed on the distal flank of the terminal moraine deposited during the 1948 surge of Kongsvegen. The stratified muds from the second core contain varying amounts of clasts and also occur on top of the debris lobe. They reveal a relatively distal glacimarine environment mainly influenced by suspension settling from turbid meltwater emanating from Kronebreen or Kongsvegen. Geochemical fluctuations indicate temporal variations in the sediment supply from the two glaciers after 1948. The few landforms in the outer parts of the study area suggest glacial activity unrelated to the glacier surges. Together with the landforms previously documented from outer Kongsfjorden and its adjacent trough (Kongsfjordrenna), the mega-scale glacial lineations in the outer part of the study area indicate part of a landform assemblage deposited from a fast-flowing ice stream during the Last Glacial Maximum. URI: http://hdl.handle.net/10037/5212 File(s) in this item: 1
thesis.pdf (8.736Mb) -
Maurer, Anina (Master thesis; Mastergradsoppgave, 03-Sep-2012)[+][-]
Abstract: This thesis assesses the obligations of landlocked states (LLSs) to protect the marine environment as a whole. In order to limit the scope, three international instruments are focussed upon: the United Nations Convention on the Law of the Sea (UNCLOS), the Convention on Biological Diversity (CBD), and the Fish Stocks Agreement (FSA). This thesis then goes one step beyond the existing regulations, and brings the obligations to protect the marine environment in conjunction with the participation in regional fisheries management organisations (RFMOs). It is examined what role RFMOs play in the protection of the marine environment and if there is a right for LLSs to accede to RFMOs with the sole interest of marine environmental protection. The focus lies again on the UNCLOS, the CBD, and the FSA. Furthermore, the extension of the powers of RFMOs from fisheries management to additional protection of the marine environment is discussed. In order to understand the role of LLSs in using and protecting the oceans, it is important to know the modalities of the right to transit and the right to access to the sea. It is therefore assessed whether landlocked states have a right to transit and a right to access to the sea, and how these rights are regulated. Throughout the whole thesis, a special emphasis is put on the case of Switzerland. All general discussions regarding rights and obligations of LLSs are adapted to Switzerland’s position as feasibly possible. URI: http://hdl.handle.net/10037/5121 File(s) in this item: 1
thesis.pdf (818.5Kb) -
Elvenes, Sigrid (Master thesis; Mastergradsoppgave, 12-Jun-2009)[+][-]
Abstract: Oppgaven beskriver og tolker storskalalandskap og geomorfologiske formelementer og prosesser på Vesterålsbanken, som er en del av norsk kontinentalsokkel mellom 68 og 70°N. Svært detaljerte batymetri- og backscatterdata (dybde og akustisk reflektans) er behandlet i GIS (geografiske informasjonssystemer), og resultatene blir presentert i form av kart. Vesterålsbanken er et område som er preget av glasiasjon selv om dynamikken i den lokale isen har vært begrenset i forhold til andre steder på sokkelen. Det interne forholdet mellom formelementer som glasiale lineasjoner dannet under hurtigstrømmende is, isfjellpløyespor, morenebanker og De Geer-morener danner grunnlaget for en enkel modell for isens dynamikk under maksimal glasiasjon og under den siste deglasiasjonen. Backscatterdata verifisert med videoopptak av havbunnen er utgangspunkt for et kart over sedimentfordelingen i et mindre område på Vesterålsbanken. Biologiske data fra ulike kilder er også trukket inn for å prøve å korrelere kartlagte bunntyper med forekomsten av kommersielt interessante fiskeslag, men dette har foreløpig ikke latt seg gjøre med de tilgjengelige dataene. Masteroppgaven har vært gjennomført i samarbeid med Norges geologiske undersøkelse (NGU) og MAREANO (marin arealdatabase for norske kyst- og havområder). URI: http://hdl.handle.net/10037/2474 File(s) in this item: 1
thesis.pdf (7.199Mb) -
Thorstensen, Lene (Master thesis; Mastergradsoppgave, May-2011)[+][-]
Abstract: Feltarbeid og analyser av batymetriske-, seismiske- og gravimetriske data er sammenstilt for å korrelere tektoniske elementer i ytre del av Senja og Kvaløya i Troms. Berggrunnen i kystområdene på nordøstlige Senja og Kvaløya i Troms tilhører Vest-Troms gneis region og består av neoarkeiske og paleoproterozoiske tonalittisk gneis og mafiske intrusiver (Kattfjordkomplekset), samt metasuprakrustale og metavulkanske bergarter (Torsnes- og Astridalbelte). Foliasjonen stryker NV-SØ og endrer orientering til VNV-ØSØ og er definert som F3 folder. Endring i foliasjonens fall er definert som F2 folder og kartlagt over hele studieområdet. Foldingen av de prekambriske bergartene er ansett som et resultat av polyfase folding i forbindelse med svekofennisk deformasjon. NV-SØ strykende strukturer på land definert som duktile skjærsoner og kan følges på den grunnedelen av batymetrien og er styrt av den prekambriske hovedtrenden. Det antas at også at de NV-SØ strykende forkastningene i de dypere delene også er strukturstyrte og faller sammen med Senjabruddsone. Mesozoiske sprø forkastninger og sprekker stryker NØ-SV til NNØ-SSV og er hovedsakelig foliasjons kuttende. Lokalt opptrer sprøforkastninger subparallelt til den prekambriske foliasjonen det vil si i hengselsonen til regionale F3 folder. Forkastningene på land er relatert til det NØ-SV strykende Vestfjord-Vanna forkastnings kompleks. Undersøkelser av seismiske data viser en dominerende forkastnings trend som stryker NØ-SV til NNØ-SSV og er relatert til Troms Finnmark Forkastnings Komplekset. URI: http://hdl.handle.net/10037/3416 File(s) in this item: 1
thesis.pdf (13.20Mb) -
Bektesevic, Emina (Master thesis; Mastergradsoppgave, 15-Sep-2011)[+][-]
Abstract: PROBLEMSTILLING: LASIK og overflatelaserbehandling er to operasjonsteknikker som brukes i behandling av myopi, hvorav LASIK er den mest utbredte. Denne studien ser nærmere på forutsigbarhet, stabilitet og effektivitet av LASIK over en 11- årsperiode, samt forutsigbarheten og stabiliteten av en ny overflatelaserbehandlingsteknikk – Custom transepithelial ”no-touch” (cTEN) over en ett-årsperiode. METODE: En meta-analyse av LASIK-resultater og retrospektiv analyse av 117 øyne behandlet med cTEN dannet grunnlaget for sammenligning av de to metodene. Analysedelen omhandlende behandlingsresultater av LASIK var basert på litteraturstudier, og den nødvendige litteraturen ble funnet ved systematiske søk i Pubmed Database. Resultatene brukt i den statistiske analysen av cTEN har opphav i 117 øyne behandlet med cTEN ved Synslaser Tromsø i perioden 01.01.09 – 31.06.09. RESULTATER: Analyse av behandlingsresultatene etter LASIK viser en gradvis regresjon av sfærisk ekvivalent 11 år postoperativt, dog er denne tilstrekkelig lav til at pasientene affisert av dette, forblir lavmyope. Ved LASIK- behandling er det de moderat myope som oppnår høyest korreksjonsmengde, mens de lavmyope får lavest sfærisk ekvivalent. Pasienter behandlet med cTEN kan få en lett overkorreksjon. KONKLUSJON: Behandling med LASIK og cTEN er forutsigbare og effektive prosedyrer for behandling av myopi. Behandling med LASIK medfører en mild regresjon i refraksjon i minst 11 år postoperativt, mens behandling med cTEN kan føre til en lett overkorreksjon som vedvarer i minst ett år postoperativt. URI: http://hdl.handle.net/10037/3731 File(s) in this item: 1
thesis.pdf (157.1Kb) -
Thorbjörg Hróarsdóttir (Journal article, 2003)[+][-]
Abstract: The aim of this paper is to present diachronic changes in terms of the conditions of first language acquisition. Grammars, seen as mental organs, may change between two generations. A change is initiated when (a population of) learners converge on a grammatical system which differs in at least one parameter value from the system internalized by the speakers of the previous generation. Learnability issues then connect to both language acquisition and language change, and understanding language changes depends on understanding how children acquire their native language. Acquisition is a process in which Universal Grammar (UG) interacts with a context-specific set of Primary Linguistic Data (PLD: the linguistic input to the child-learner) and uses these PLD as the source for triggers or cues that map the innate (preexperience) knowledge to a mature grammar. If a certain phenomenon has survived through many generations, it must have been reflected clearly in the PLD. Then, if we note that it has changed, something in the language performance of the previous generation must have changed, and thereby paved the way for a new interpretation. Innovation leading to linguistic variation in the PLD and gradual changes in PLD play a central role in the explanation here: the immediate cause of a grammar change must lie in some alternation in the PLD. We will look at how the language spoken in a certain community (E-language) may gradually become different from the language that originally served as the triggering experience. These changes in the E-language also mean changes in the input available to the child-learners of the next generation and a motivation for a different parameter setting has arisen. Description: In special issue: Proceedings of SCL 19 URI: http://hdl.handle.net/10037/255 File(s) in this item: 1
article.pdf (49.27Kb) -
Figenschou-Cedewarft, Leif André (Master thesis; Mastergradsoppgave, 06-Jun-2007)[+][-]
Abstract: I hvilken grad får lang tids bruk betydning ia dganegne til marine ressurser og i allokeringen av ressurser mellom konkurrerende stater? URI: http://hdl.handle.net/10037/1017 File(s) in this item: 1
thesis.pdf (611.7Kb) -
Kube, Ralph; Garcia, Odd Erik; LaBombard, Brian; Terry, James L.; Zweben, Stewart (Conference object; Konferansebidrag, 2012)[+][-]
-
Zeigler, Harald Bergersen (Master thesis; Mastergradsoppgave, 02-Jun-2008)[+][-]
Abstract: The theme for the master thesis is simulation of homogeneous, isotropic turbulence. I have shown that the energy of the velocity field is decaying in time, but the comparison to the reference solution is however invalid, due to the fact that the reference solution may have scalings that are not obvious to the observer, and that my own simulation results seemed to behave quite strange, with a sudden fall of energy in the first time-steps, which I have no explanation for why happened. The thesis consists of a rather large theory section and a smaller discussion in the end. Chapters 3 and 4 are mainly introductory and addressing the theme and job description. They also serve as mild introductions to tuirbulence theory as well as mathematical, numerical subjects. Overall, the reader is assumed not to be very familiar with mathematical terms, applied mathematics and physics, so many terms are explained. The provided theory is designed to teach a reader totally unfamiliar with science some things, but not all. The author has not forgot about the experienced reader who may be an expert in the field, and the level of the thesis should be high enough for that person also to maintain interest while reading. URI: http://hdl.handle.net/10037/1642 File(s) in this item: 1
thesis.pdf (653.3Kb) -
Engelskjøn, Ragnhild (Journal article, 2003)[+][-]
-
Knutsen, Nils Magne (Chapter; Bokkapittel, 2004)[+][-]
-
Rydningen, Tom Arne; Vorren, Tore Ola (Conference object; Konferansebidrag, 2011)[+][-]
-
Sanchez Borque, Jorge (Master thesis; Mastergradsoppgave, May-2009)[+][-]
Abstract: 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 a glacimarine environment, i.e. the channels are inferred to have been formed by turbidity currents originating from glacial meltwater on the deepest reflector. On shallower reflectors, megascale glacial lineations, ridges and parts of hill-hole pairs indicate that grounded ice reached the paleo-shelf edge at least six times in the last 1.5 Ma. Moreover, two of the shallower seismic units show indications of sediment blocks that are inferred to have been subglacially eroded, transported and deposited by ice streams. The influence of the ice stream flowing from the Bjørnøyrenna in the last 330 ka is evident in the Veslemøy High; however, the origin of the ice streams is unclear on older paleo-surfaces. URI: http://hdl.handle.net/10037/1911 File(s) in this item: 1
thesis.pdf (11.38Mb) -
Sørensen, Steffen Aagaard (Doctoral thesis; Doktorgradsavhandling, 22-Mar-2011)[+][-]
Abstract: The overall objective for this PhD-study was to further advance the understanding of the oceanographic variability and development in the Nordic Seas during the Late Glacial and the Holocene and towards the present. The focus is specifically on the poleward Atlantic Water advection along the continental margins of Norway, into the SW Barents Sea and along the West Spitsbergen slope. Four high resolution sediment cores retrieved from northern continental shelve allowed examination of spatial and temporal oceanographic and environmental variability and elucidation of underlying forcing mechanisms. The sediment cores were investigated using several paleoceanographic proxies. These include planktic and benthic foraminiferal fauna distributions, measurements of stable isotopes (δ18O, δ13C) on foraminiferal tests and transfer function SST reconstructions based on planktic foraminifer species counts. Grain size analysis, IRD counts, clay mineral analysis and chemical analysis of bulk sediment carbon content were also used. Additionally the relatively new paleothermometer, the Mg/Ca-ratio, was applied on planktic and benthic foraminifera to test and examine its applicability in Subarctic and Arctic environmental settings. The Mg/Ca-ratios were used to constrain reconstructions of sea surface and bottom water temperatures. Furthermore, Mg/Ca-ratios combined with isotopic measurements performed on the same foraminiferal species were used for quantization of past oceanic salinity changes. Weak Atlantic Water influence was observed briefly at around 18,700 and after 15,000 cal yr B.P. in the SW Barents Sea indicating an early deglaciation of Ingøydjupet. Sub surface Atlantic Water inflow was observed from the beginning of the records (at 14,000 cal yr B.P.) in both the eastern Fram Strait and in Andfjorden. Atlantic Water influx was diminished during the Younger Dryas at all investigated core sites. Strong inflow of Atlantic Water resulted in emergence at the surface during the glacial – interglacial transition. The emergence had a south-north time delay of ca. 1,000 years which probably can be ascribed to increasing influence from a lingering pool of sea-ice and melt water towards the north. Reconstructed temperatures of Atlantic Water entering the Arctic Ocean through the eastern Fram Strait show a ~2°C warming during the last ca. 100 years. This warming is unprecedented over the past 2000 years and is probably linked to the Arctic amplification of global warming. Description: Papers 1, 2 and 5 are not available in Munin due to publishers' restrictions:
1. S. Aagaard-Sørensen, K. Husum, M. Hald, J. Knies: 'Paleoceanographic development in the SW Barents Sea during the Late WeichselianeEarly Holocene transition',Quaternary Science Reviews 29 (2010) 3442-3456. Paper available at http://dx.doi.org/10.1016/j.quascirev.2010.08.014
2. J. Junttila, S. Aagaard-Sørensen, K. Husum and M. Hald: 'Late Glacial–Holocene clay minerals elucidating glacial history in the SW Barents Sea', Marine Geology 276 (2010) 71–85. Paper available at http://dx.doi.org/10.1016/j.margeo.2010.07.009
5. Spielhagen, R. F.,Werner, K., Aagaard-Sørensen, S., Zamelczyk, K., Kandiano,E., Budeus, G., Husum, K., Marchitto, T. and Hald, M.:'Enhanced Modern Heat Transfer to the Arctic by Warm Atlantic Water', SCIENCE(2011), 331, 450-453. Paper available at http://dx.doi.org/10.1126/science.119739URI: http://hdl.handle.net/10037/3007 File(s) in this item: 3
paper_3.pdf (1.151Mb)paper_4.pdf (2.138Mb)thesis.pdf (818.7Kb) -
Maniaol, Angelina; Elsais, Ahmed; Lorentzen, Åslaug Rudjord; Owe, Jone Furulund; Viken, Marte K; Sæther, Hanne Skarpodde; Flåm, Siri Tennebø; Bråthen, Geir; Kampman, Margitta Theodora; Midgard, Rune; Christensen, Marte; Rognerud, Anna Kaja; Kerty, Emilia; Gilhus, Nils Erik; Tallaksen, Chantal; Lie, Benedicte Alexandra; Harbo, Hanne Flinstad (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)[+][-]
Abstract: Acquired myasthenia gravis (MG) is a rare antibody-mediated autoimmune disease caused by impaired neuromuscular transmission, leading to abnormal muscle fatigability. The aetiology is complex, including genetic risk factors of the human leukocyte antigen (HLA) complex and unknown environmental factors. Although associations between the HLA complex and MG are well established, not all involved components of the HLA predisposition to this heterogeneous disease have been revealed. Well-powered and comprehensive HLA analyses of subgroups in MG are warranted, especially in late onset MG. This case-control association study is of a large population-based Norwegian cohort of 369 MG patients and 651 healthy controls. We performed comprehensive genotyping of four classical HLA loci (HLA-A, -B, -C and -DRB1) and showed that the DRB1*15:01 allele conferred the strongest risk in late onset MG (LOMG; onset ≥60years) (OR 2.38, pc7.4×10−5). DRB1*13:01 was found to be a protective allele for both early onset MG (EOMG) and LOMG (OR 0.31, pc 4.71×10−4), a finding not previously described. No significant association was found to the DRB1*07:01 allele (pnc = 0.18) in a subset of nonthymomatous anti-titin antibody positive LOMG as reported by others. HLA-B*08 was mapped to give the strongest contribution to EOMG, supporting previous studies. The results from this study provide important new information concerning the susceptibility of HLA alleles in Caucasian MG, with highlights on DRB1*15:01 as being a major risk allele in LOMG. URI: http://hdl.handle.net/10037/4906 File(s) in this item: 1
article.pdf (991.7Kb) -
Koehl, Jean-Baptiste Philippe (Master thesis; Mastergradsoppgave, 29-May-2013)[+][-]
Abstract: 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 fault rocks. As a result of the present study,two major sets of onshore brittle faults have been observed, trending NNE-SSW and ENE-WSW,and they are tentatively correlated in two, NE-SW trending fault complexes: the Rekvika and the Vestfjorden-Vanna fault complexes. These fault complexes run parallel to the Troms-Finnmark fault complex that borders major offshore sedimentary basins in the NW. On the one hand, the Vestfjorden-Vanna fault complex defines the southeastern boundary of the West Troms Basement Complex towards the Caledonian nappes, and is made of wide fault zones that have experienced major displacement (ca. 1-3km). On the other hand, the Rekvika fault complex is considered as an intra-horst fault system composed of narrow fault zones that are thought to have accommodated low amounts of displacement (> 250 m). On a local scale, the fault zones display similarities in attitude (trend and dip) with the Caledonian and Precambrian fabrics, indicating a possible influence of pre-existing zones of weakness on brittle faulting. The dominant deformation mechanism (cataclastic flow) indicates pressure range about 0.2-0.3 GPa, i.e. 5-10 km depth for the formation of the cataclastic fault rocks, and these fault rocks contain mineral assemblages that generally indicate temperatures about 350-500ᵒC. This suggests that the West Troms Basement Complex has been largely uplifted later on, until present level. The NNE-SSW and ENE-WSW trending fracture sets are believed to have formed synchronously due to WNW-ESE extension, during an early stage of rifting in the Permian-Early Triassic. The NNE-SSW trending faults likely represent the main fault system, orthogonal to the extension direction, and the ENE-WSW trending faults may correspond to oblique transfer zones that link the NNE-SSW fault segments. An alternative model implies NW-SE trending transfer zones to link the NNE-SSW trending faults. A late stage of minor reverse reactivation of the NNE-SSW and ENE-WSW trending faults, and the development of NW-SE striking fractures are tentatively correlated to ridge-push forces during the opening of the North Atlantic in the Eocene. URI: http://hdl.handle.net/10037/5214 File(s) in this item: 1
thesis.pdf (8.426Mb) -
Baeten, Nicole Jeanne (Master thesis; Mastergradsoppgave, Nov-2007)[+][-]
Abstract: Three sediment cores, swath multibeam bathymetry data and high-resolution seismic data from Billefjorden, Svalbard have been analysed for a better understanding of the Late Weichselian and Holocene glacier activity as well as sedimentary process and glacigenic deposits in the fjord. The data reveal that glacial linear features were generated in the central part of Billefjorden while it was filled with ice draining the Svalbard-Barents Sea ice sheet during the Last Glacial. A till in the bottom of a sediment core from the central part of the fjord is inferred to have been deposited before the ice front retreated into Billefjorden around 11230 cal. years BP. An overlying glacimarine unit deposited between c. 11230 and 11200 cal. years BP indicates that the glacier retreated from central parts of the fjord to the fjord head in approximately 30 years. Annual recessional moraines deposited during this period suggest that the glacier front retreated approximately 330 m/ year at the end of the last Glacial. High concentration of shells, low amounts of IRD and XRD results indicate a Holocene climatic optimum between c. 11200 – 7930 cal. years BP in which Nordenskiöldbreen was most likely much smaller than it is at present. XRD results and comparatively high amounts of IRD point to a complex pattern of ice rafting between c. 7930 and 3230 cal. BP. IRD deposited before c. 5470 cal. years BP was most likely transported by sea ice, whereas IRD after 5470 cal. years points towards a growth of Nordenskiöldbreen. The time after c. 3230 is mainly characterised by suppressed rafting of sea ice and icebergs because of the possible presence of multi-year shorefast sea ice during the Neoglacial maximum. Glacial lineations on a bedrock terrace in the inner fjord were formed during a Neoglacial advance of Nordenskiöldbreen. Iceberg ploughmarks and recessional moraines were most likely generated during the retreat after the maximum Neoglacial extent of Nordenskiöldbreen. Mass-transport activity in Billefjorden probably occurred throughout the entire Holocene. There might haven been an increased mass-transport activity shortly after the deglaciation of the fjord, because high rates of isostatic uplift might have caused seismic activity. Other triggering mechanisms include the development of oversteepened slopes by high sediment supply and the pushing of sediments at the grounding line of the glacier. Pockmarks in the central part of the fjord were most likely generated by the seepage of thermogenic gas along the Billefjorden fault zone. URI: http://hdl.handle.net/10037/1274 File(s) in this item: 1
Thesis.pdf (42.43Mb)
Search Munin
Browse
-
All of Munin
Help
Munin is powered by DSpace 1.8.2
The University Library of Tromsø, N-9037 Tromsø
Tel: +47 77 64 40 00, E-mail: munin@ub.uit.no