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a function of chemical weathering. Local varia-
tion in precipitation in the hinterland, reflecting
variation in altitude, relief and atmospheric cir-
culation pattern, may also have attributed to dif-
ferences in sediment delivery along the coastline
of the Jameson Land Basin.
Neill Klinter Group in Jameson Land Basin and
the Båt and Fangst groups on the Halten Terrace-
Trøndelag platform has been suggested by Dam &
Surlyk (1995, 1998) and Gjelberg (in Johannessen &
Nøttvedt, 2008). However, lateral facies variation,
sequence stratigraphic architecture and presence of
incised valleys in the Neill Klinter Group reveal a
more composite relationship between the two basin
areas rather than a direct correlation. The presence
of incised valleys in the Neill Klinter Group dem-
onstrates that there are basic local deviations
between the two basinal settings. Despite the differ-
ences, important similarities between the Early
Jurassic Jameson Land and Halten Terrace basins
make the Neill Klinter Group a reference object
for petroleum reservoirs on the mid-Norwegian
continental shelf. Corresponding incised valleys as
those shown to be present in the Neill Klinter
Group may also occur on the mid-Norwegian conti-
nental shelf in successions of same age. Conceptual
depositional models and qualitative and quantita-
tive data concerning dimensions, geometry, facies
variation and potential connectivity of sandstone
bodies obtained from the Neill Klinter Group can
be used to improve static and dynamic reservoir
models of tide-influenced heterolithic reservoir
sandstones on the Norwegian continental shelf and
probably also in other petroleum provinces of the
World located in other marginal marine and tide-
influenced basins similar to the Early Jurassic
Jameson Land Basin.
Neill Klinter Group as an analogue for reservoir
sandstones on the Halten Terrace
During the Early Jurassic, very similar paralic and
overall heterolithic successions were deposited
in shallow marine sag and rift basins on both sides
of the proto-Norwegian-Greenland Sea, in East
Greenland and the present mid-Norwegian conti-
nental shelf, respectively (see above). As indicated
by Dam & Surlyk (1995, 1998) and Surlyk (2003)
there are several similarities that regard stratigra-
phy and sedimentological features between the
Neill Klinter Group in the Jameson Land Basin and
the Båt Group and partly the overlying Fangst
Group (Aalenian-Callovian), on the Halten Terrace-
Trøndelag Platform.
The similarities between the Neill Klinter and
Båt groups include (1) comparable overall regional
structural setting along the same seaway on the
same lithospheric plate, in the same palaeolatitude
and climatic belt; (2) great similarity in depositional
history controlled by regional to eustatic variations
in sea-level; (3) basal paralic heterolithic and low-
gradient mixed-energy delta systems and homoge-
neous deltaic systems interfingering with offshore
fines in the middle part of both groups and (4) com-
parable style and scale of various types of deposi-
tional architectural elements and their internal
facies and heterogeneities.
The Neill Klinter and the Båt groups also reveal
several differences in setting and properties. These
differences comprise (1) structural setting as the
result of differences in local pre-rift and syn-rift
development on the two sides of the proto-Norwe-
gian-Greenland Sea, including high frequency
local base-level changes; (2) basin dimensions; the
Båt Group on the Halten Terrace covers a basin
area four times larger than that of Neill Klinter
Group; (3) localised variation in precipitation, run-
off and sediment influx between the two basin
areas; (4) magnitude and distribution of autogenic
processes (fluvial, tidal, waves) in relation to acco-
mmodation space; (5) sediment supply rates and
type of sediments.
A direct lithostratigraphic or a one-to-one
sequence stratigraphic correlation between the
CONCLUSIONS
1
In contrast to previous descriptions of the
Early Jurassic Jameson Land Basin, no eastern
basin marginal fault has been shown, nor any
intra-basinal NW-SE cross-faults that separate
the southern from the northern Jameson Land
Basin. The eastern boundary is an onlap
contact. Thickness variation within the Neill
Klinter Group is related to differential subsid-
ence subsequent to Permo-Triassic rifting.
2
The Neill Klinter Group consists of a lower
stratigraphic compartment, formed as an overall
prograding wave-influenced to tide-influenced
deltaic depositional system and an upper strati-
graphic compartment of an overall retrograding
series of stacked tide-dominated incised valley
successions and wave-dominated delta deposi-
tional systems.
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