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the Chalk Group in the Norwegian Central Graben,
while Bramwell et al . (1999) postulated that chalk
deposition occurred between the effective
wave  base and 300 m. Based on sedimentological
evidence, trace fossil assemblage and vertical
difference in the topographic relief of a moat-drift
complex, Surlyk & Lykke-Andersen (2007)
estimated an average water depth of 300 m to 400 m,
with peak of 600 m, for the chalk successions in the
Danish Basin. Surlyk et al . (2008) pointed out that
it is difficult to estimate the depth of chalk deposi-
tion, because depositional processes below wave
base are similar and practically depth-independent.
However, the postulated water depths are within
the range estimated by Viana et  al . (1998) for
mid-water (300 m to 2000 m) and shallow-water
(50 m to 300 m) bottom current systems.
The current that formed the channel in the
present case is inferred to have flowed principally
southward, similarly to the current directions
identified by Surlyk et 
Maastrichtian chalk of the German North Sea
sector. A southerly direction is also comparable to
the direction of the currents interpreted by Jarvis
(1980) and Esmerode et al . (2008) in the Santonian
and Turonian to Campanian successions of the
Paris Basin and Danish Central Graben, respec-
tively. These current directions differ markedly
from the NW direction interpreted in the Danish
Basin (Fig.  20) (Esmerode et  al ., 2007; Surlyk &
Lykke-Andersen, 2007).
The channel in the present study is thus consid-
ered to be a local feature formed within an extensive
system of currents (Fig.  20) that drove water
circulation in the Chalk Sea since the Cenomanian.
In the Norwegian North Sea, this system of bottom
current principally flowed southwards along the
Central Graben before being funnelled by sea floor
topography and forced to flow upslope along the
northern flank of the Lindesnes Ridge. The current
then passed through the Feda Graben before
reaching the Danish and German sectors of the
al . (2008) in the
N
Late Cretaceous sea
during maximum sea level
Land mass
Structural high
Normal fault
North Sea
Basin
Polish Trough
Paris
Basin
400 km
Current direction from this study
Current directions based on seismic evidence
Current directions from other published studies
Fig. 20. Palaeogeographical map showing the extent and directions of the Late Cretaceous marine circulation in NW
Europe. Simplified from Ziegler (1990), with palaeocurrent directions based on seismic data after Lykke-Andersen & Surlyk
(2004), Esmerode et al . (2007, 2008), Surlyk & Lykke-Andersen (2007), Surlyk et al . (2008) and Esmerode & Surlyk (2009)
and other interpretations from Jarvis (1980) and Hart (2007).
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