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(A)
Møre Marginal High
Central Møre Basin
Grip High
Ormen Lange Dome
Slørebotn Subbasin
1
°
E
2
°
E
3
°
E
°
E
°
E
°
E7
°
E
64
°
N
63
°
N
50 km
Plio-Pleistocene
Eocene
Maastrichtian
San-Con-Tur
Lower Cretaceous
62
°
N
Mio-Oligocene
Palaeocene
Campanian
Cenomanian
6305/12-2
Lowermost Cretaceous
6305/12-1
6205/3-1
(B)
6305/7-1
6305/5-1
6305/8-1
10 km
10 km
10 km
(C)
Basinfloor
Ramp margin
Shelfal to Shallow marine
Exposed hinterland
Healed
base-of-
slope
Ponded
slope
Healed
slope
“Above grade”
slope
Møre
Margin
Slørebotn
Subbasin
Ormen
Lange
sub-
basin
Intra-
basinal
high
Gossen
High
Eastern
Møre
Basin
Fig. 3.
Partly conceptualised geo-section (A) and seismic lines (B) across the Ormen Lange area. The geo-section runs from
the Møre Margin (Slørebotn Subbasin) to the south-east and into the western Møre Basin to the north-west. Only the
Cretaceous, Palaeogene and Neogene stratigraphy is shown. Note variations in thickness and seismic character and facies
of the Upper Maastrichtian and Danian Ormen Lange reservoir sections from upslope minibasins to the east to the
downslope Ormen Lange subbasin to the west. For location of structural elements shown in A, reference is made to Fig. 2B
and (C) Inferred basin margin topography during the Maastrichtian and Danian.
& Ebbing, 2008), acted as the south-eastern slope-
margin to the Møre Basin during most of the Late
Cretaceous and Early Palaeogene (Brekke, 2000;
Færseth & Lien, 2002; Martinsen
et al
., 2005).
During the Late Cretaceous to Early Palaeogene
rift episode, the Møre Margin and eastern Møre
Basin was progressively rotated basinward (i.e.
tilted westward) in a stepwise manner during the
successive rift phases. The stepwise tilting of the
Møre Margin is attributed to temporal variations
in subsidence rates of the Møre Basin, as well as
uplift rates of the Norwegian hinterlands. This
was a response to the successive rift phases that
occurred along the western Møre Basin. Basinal
subsidence rates increased from the Late
Campanian onwards, as the Norwegian-Greenland
Sea rift system gradually progressed from slow to
rapid rifting rates as the rift evolved towards
break-up. Uplift of the Norwegian hinterlands was
probably already initiated in the Turonian or
Coniacian (cf. Martinsen
et al
., 1999) and proba-
bly was accentuated from the Maastrichtian
onwards in response to the transition into the
rapidly extending rift interval with increased
intensity and degree of structuring.
Reactivation of or compaction over underlying
Jurassic subbasins and highs is argued to have
progressively changed the slope profile along the
Møre Margin in the Late Cretaceous. During the
Turonian and Coniacian, the Møre Margin formed
the south-eastern, gently sloping, broad ramp
margin to the Møre Basin. In the Santonian to
Campanian, it changed to an increasingly steeper
margin with a more pronounced shelf-slope
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