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dc.contributor.advisorMienert, Jürgen
dc.contributor.advisorBünz, Stefan
dc.contributor.authorFrantzen, Jon Hermann Pilskog
dc.date.accessioned2009-01-26T10:55:51Z
dc.date.available2009-01-26T10:55:51Z
dc.date.issued2008-11-15
dc.description.abstractThe Vestnesa Ridge is a 100 km long and ≈3 km wide sediment drift NW of the Svalbard Margin deposited on young oceanic crust. The crest of the Vestnesa Ridge is pierced by 133 pockmarks, where the orientation and elongation is controlled mainly by processes such as positioning of faulting, creeping of sediments or similar down-slope processes. High resolution single seismic reflection data together with chirp data across these pock-marks allowed connecting the potential fluid flow pathways in the sub seabed such as acoustic chimneys and faults to the pockmarks at the seabed. The acoustic datasets encompass very high resolution swath bathymetry data gridded to 15m together with very resolution chirp data. A cross cutting BSR (bottom- simulating reflection) exists in the study area defining the base of the GHSZ (Gas hydrate stability zone), that becomes shallower towards the spreading zone due to increases in heat flow. The GHSZ overlays an approx. 150 m thick layer with en-hanced amplitude reflections suggesting considerable amounts of free gas beneath the GHSZ. Due to reduced permeability in hydrated sediments, gas apparently migrates below the GHSZ along the flanks of Vestnesa Ridge upwards towards the crest. Here the pressure builds up as it get trapped below the GHSZ. Acoustic chimneys connects to the seabed pockmarks and pierce through the GHSZ providing a pressure valve for the free gas zone directly beneath the BSR and possibly for the deep acoustic turbidity zone, where gas may accumulate. Suggested source regions of fluid flow encompass both a depth window for thermogenic gas and a shallow temperature window for biogenic gas.en
dc.format.extent9392376 bytes
dc.format.extent2078 bytes
dc.format.mimetypeapplication/pdf
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dc.identifier.urihttps://hdl.handle.net/10037/1734
dc.identifier.urnURN:NBN:no-uit_munin_1452
dc.language.isoengen
dc.publisherUniversitetet i Tromsøen
dc.publisherUniversity of Tromsøen
dc.rights.accessRightsopenAccess
dc.rights.holderCopyright 2008 The Author(s)
dc.subject.courseIDGEO-3900nor
dc.subjectVDP::Matematikk og naturvitenskap: 400::Geofag: 450::Marin geologi: 466en
dc.subjectApplied geophysicsen
dc.subjectFluid flowen
dc.subjectPockmarken
dc.subjectAcoustic chimneyen
dc.subjectVestnesa Ridgeen
dc.subjectKnipovich Ridgeen
dc.subjectMolloy Transformen
dc.subjectKongsfjorden channelen
dc.subjectMarin geologyen
dc.titleFluid-flow expressions at Vestnesa Ridge of the NW -Svalbard Marginen
dc.typeMaster thesisen
dc.typeMastergradsoppgaveen


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