Tertiary Tectonostratigraphic Evolution of the Veslemøy High and Central Part of the Sørvestsnaget Basin
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- Studentoppgaver (TN-IER) 
Previous geologically works in Sørvestsnaget Basin and Veslemøy High region, suggest thatTertiary reservoirs in the western Barents Sea are promising, but not yet properly understoodlaterally, with the influence of regional and local tectonics. This thesis focuses on understandingthe lateral and vertical variation of the Tertiary succession, and how the tectonics influencedthe deposition of reservoirs, using 2D and 3D seismic data, together with provided well logs. A major and thick Tertiary succession is present in the western Barents Sea in areas such asSørvestsnaget Basin. The Paleocene and Eocene seismic units are influenced by normal faultingand rifting tectonics in Sørvestsnaget Basin, while the seismic units over Veslemøy High weredeposited in a less tectonic active period, especially in Paleocene, before a major uplift eventaffected this high during the Eocene. At the western margin of the Sørvestsnaget Basin, amarginal high was uplifted, probably time equivalent to the uplift of Veslemøy High duringEocene, but at a significantly smaller scale. Major depocenters were present in SørvestsnagetBasin due to salt mobilization of a major salt diapir in the south eastern margin of the basin,triggered during Eocene. Possible reactivation is suggested by depocenters. Glacial isostasyfrom the Pliocene have led to further uplift and subsequently subsidence, causing theaccumulation of a large clastic erosional glacial wedge deposited in the generatedaccommodation space, mainly Sørvestsnaget Basin. Normal faulting, together with uplift (marginal high, Veslemøy High and the salt diapir) andsubsidence events have greatly affected the Tertiary succession, and routed/deflected the postEocene (post rift) deposits and localized them into preferential areas in Sørvestsnaget Basin,situated in the western Barents Sea. Syn kinematic wedges are found to be controlled by normalfaulting in Sørvestsnaget Basin and at the bounding fault between the Sørvestsnaget Basin andthe Veslemøy High, in Paleocene to Eocene. Turbiditic flows controlled by local footwall uplift,rotation and erosion are found in hanging walls of the Paleocene seismic unit, together with thesyn kinematic wedges in the Sørvestsnaget Basin. Injectite features are found to be common inPaleocene and Eocene, probably triggered by earthquakes related to local faulting activity, aswell as differential compaction. The uplift of Stappen High have caused the deposition of alarge sand rich submarine fan in the Sørvestsnaget Basin, while at the approximately same time,salt halokinetic movements controlled the deposition of a mass transport complex in proximityof the salt diapir. Pliocene shelf margin clinoforms are found to be prograding towards the west,sourced by isostatic uplift of the Barents Sea. Within the clinoforms, a vast submarine channelbelt shows signs of erosion, transportation and deposition.