The Cenozoic development of the Norwegian margin between 60 and 64°N can be described in terms of five, unconformity-bounded, megasequences: Paleocene–lowermost Eocene (65–51 Ma), Lower Eocene–lowermost Oligocene (51–31 Ma), Lower–upper Oligocene (31–24 Ma), Miocene–Pliocene (24–1.9 Ma), and Pleistocene (1.9 Ma–present). Each sequence is constructed of systems tracts, varying in type and number between sequences. In the Møre Basin (62–64°N), lowstand wedges dominate and form an offlapping, regressive pattern. In the Northern North Sea Basin (60–62°N), lowstand, transgressive and highstand systems tracts are present, showing a more variable framework.The variability observed is interpreted to reflect the response of sediment supplied, both in time and space, into different basin physiographies related to the overall tectonic context of the two areas. The Northern North Sea Basin in the Cenozoic received sediments generated from the basin margins in periods of uplift and lowstand. Clastic systems probably prograded into a gradually-shallowing central basin area, formed as a response to decaying, post-rift subsidence, margin uplift and sediment fill. The Møre Basin, in contrast, acted as a margin to incipient and on-going North Atlantic rifting, and the basin physiography was that of a more steeply inclined slope facing the northwest. Larger water depths caused sediment wedges to be restricted to the basin margin rather than acting as fill of the central basin area such as occurs in the North Sea. The offlapping pattern probably records repeated uplift of the Norwegian mainland, shedding sediments into the basin.

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The giant OrmenLange GasFieldi ss ituated int he MøreB asin,N orwegianSea, atw aterdepths around1000 m. The reservoirintervalconsists ofalowerheterolithic unitmainly ofMaastrichtianage (Jorsalfare Formation) andanuppersandstoneunitofDanianage (Egga Member,VåleFormation),separated byawidely distributed mudstoneunit('VåleTight'),andconsistsofbothhigh andlow density turbiditesinassociation with fine-grained backgroundsediments. The reservoirintervalspans the Cretaceous-Tertiary boundary,withoutany major stratigraphic breaks. The mainarchitecturalelements ofthe reservoirare: channel-dominated deposits, channelized lobe deposits andnon-channelized frontals playo rfanfringe deposits. The spatialdistribution of thesef acieselements indicatesad ynamic systemw ithc hangingsediment supply through time.Corea ndlog studiesfrom the wells haveb eenintegrated withh igh-resolution biostratigraphyt odevelop ad ynamic depositionalmodel.Duringlatest Cretaceous andPaleocenetimes,aseriesofsubtlesub-basins developed alongthe southeastern MøreBasinmarginasaresult ofdifferentialsubsidence aboveJurassic extensionalfaults. The sub-basins created astepped slopetopographythatinfluenced the flow pattern ofturbidity currents.Inalandwardposition,east ofthe OrmenLange Field, the Cretaceous-Tertiary boundary ischaracterized bya major unconformity,i mplyinge rosion andsediment by-pass. Inearly Daniant ime, upliftandrotation ofthe provenance area to the east (Norwegianmainland)led to extensiveerosion andredistribution ofsandysediments into the MøreBasinandcaused deposition ofthe Egga Member. The turbiditesfilled the intraslopebasins initially inab asinwards-steppingsense, but laters edimentation switched landward.Onshorestructural,provenance andg eomorphologicaldata, combined withoffshorestructural,seismic and sedimentologicaldata, yielda nintegrated interpretation ofthe deep-waterdepositionals ystemint he greater OrmenLange area.Present fjordsatMøre, controlled byt he Møre-Trøndelag fault zone, werevalleys ystems thatfed sandst oapoint source updipo fthe OrmenLange area.The point source wasl ocated att he transition/relayzonebetweenanarrow shelfarea inthe southandabroad shelfarea inthe north.Inaddition to beingakeytransition zonefor bothCaledonianandJurassic structures,thiszonearea isalso the 'landing'point of the major oceanic JanMayenFractureZone.