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(A)
Joshua Mbr. (>30 m)
(B)
Josephine Mbr.
(20-60m)
Jonathan Mbr.
(60-250 m)
n = 2440
(C)
C1
Joanne Mbr.
(50-450 m)
Julius Mbr. (20-100 m)
n = 668
Judy Mbr.
(10-250m)
(D)
H
Bunter Fm. (10-130 m)
Smith Bank Fm.
(50-300 m)
n = 469
Marsh vegetation
Shrubland
Bioturbation
Salt crust fabrics
Calcic palaeosols
Desiccation
Zechstein halite
Anhydrite
Microbial laminites
Fig. 2. Central North Sea Triassic stratigraphy and facies architecture. (A) Schematic stratigraphic column of the
Smith Bank and Skagerrak formation section. H- Hardegsen Unconformity, C1- Early Cimmerian 1 Unconformity.
(B) Palaeocurrent rose for Skagerrak Formation fluvial cross-bedding, illustrating a wide scatter in orientations, but
with an overall southward trend. This trend can locally be differentiated into two discrete modes: a transverse mode
to the south-west (e.g. C, data from the Heron Field, UKCS) and an axial mode to the south-east (e.g. D, data from the
Skua Field, UKCS).
particularly in the Early Triassic and in deep,
high temperature parts of the basin, and the
broadly similar facies composition of many of
the sandstone and mudstone members. Regional
correlation therefore relies on support from
non-biostratigraphical techniques including use
of heavy minerals (Mange-Rajetzky, 1995), chem-
ostratigraphy, cyclostratigraphy (De Jong et  al .,
2006) and magnetostratigraphy (Turner et  al .,
1996). Correlation is also facilitated by distinct
stratigraphic markers such as well dated marine
limestone and evaporite intervals in the Southern
Permian Basin (e.g. Muschelkalk limestones and
evaporites, Röt and Keuper evaporites) which
can be traced into their northern facies equiva-
lents (Michelsen & Clausen, 2002).
Regional tectonic setting
Deposition of Triassic sediments in the north-west
European region occurred during the punctuated
rifting episodes that initiated the break-up of
Pangaea. Multiple extension directions were
involved in this process (Coward, 1995; Coward
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