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in this basin (Kürschner & Herngreen, 2010) record
an Early Triassic period dominated by opportunist
vegetation populating dry, well drained floodplain
environments, with a possible increase in humidity
during the latter part of the Early Triassic that may
correspond to the Smithian humid phase recorded
on the Tethyan margin (Stefani, 2010). Sporomorph
assemblages indicate generally dry to arid condi-
tions through the Anisian (van der Zwan & Spaak,
1992; Kürschner & Herngreen, 2010), with the
Early Ladinian (upper Muschelkalk) characterised
by more semi-arid conditions, again broadly fol-
lowing a similar pattern to that seen to the south
(Fig. 18). More humid conditions returned during
the Late Ladinian, with a peak in palynomorph
diversity recording the widespread expansion of
wetland floras. This Late Ladinian event is also
well expressed in the Norwegian-Danish Basin
(Lindström et  al ., 2009) and central North Sea
(Goldsmith et al ., 1995). The Early Carnian was
marked by a return to aridity, although a second
peak in species diversity occurred during the
Middle Carnian pluvial event when conditions
became wetter across the entire north-west European
region (Simms & Ruffell, 1989, 1990). During the
Late Carnian and Norian palynofloral abundance
declined as conditions returned to aridity. Local
recovery within the Stubensandstein Formation
(Hornung & Aigner, 2002) is indicative of generally
arid conditions, with minor humidification in the
Late Norian (Fig. 18). This event may also equate
to enhanced clastic transport and wetter condi-
tions across the margins of the Tethyan carbonate
shelf (Berra et  al ., 2010) and, although poorly
dated, to deposition of the Josephine Sandstone
Member in the central North Sea. The transition
into the Rhaetian was marked by widespread
humidification across the region (Ahlberg et  al .,
2002) in response to the marine inundation of the
interior of Pangaea.
The climate records from the Tethyan margin
(Stefani, 2010) and Southern Permian Basin (van
der Zwan & Spaak, 1992; Kürschner & Herngreen,
2010) appear broadly similar (Fig.  18), although
there are differences in detail and resolution due
to the variety of approaches used. The entire
region to the south of the central North Sea appears
to have been subject to widespread increases in
rainfall and fluvial runoff in the Smithian, Late
Ladinian and Middle Carnian and sustained
drought during the Spathian, Anisian and Norian.
These fluctuations were not necessarily global in
extent - palynological data from the Barents Sea
region (Hochuli & Vigran, 2010) record a different
climatic pattern of warm temperatures and minimal
seasonality, with only the Spathian and Late Anisian
drying events, together with the mid-Anisian ten-
dency towards wetter conditions being expressed
this far north. The Late Ladinian pluvial phase is
absent and the Carnian increase in humidity was
sustained through the Late Triassic rather than
reverting back to drier conditions. This partially
similar record may indicate a combination of
global temperature changes impacting all lati-
tudes (Galfetti et al ., 2007a) and more regional (i.e.
Tethyan) climate changes (Hornung et  al ., 2007);
or possibly latitudinal differences in atmospheric
response to global change as the migration range
of the inter-tropical convergence zone varied and
the scale of Hadley cells expanded and contracted
(cf. Perlmutter & Matthews, 1990). It is also possible
that Triassic atmospheric circulation patterns were
dissimilar to the present, with a breakdown of
Hadley circulation into numerous small cells, or
collapse of the Polar cell and development of a
two cell system leading to humidity at the poles
(Parrish, 1993; Kidder & Worsley, 2004). These
would give a less predictable response than migra-
tion of a simple latitudinal zonation. However,
Olsen & Kent (2000) note that Late Triassic facies
distributions do appear to follow latitudinal cli-
mate zones suggesting, at least for this period, that
Hadley circulation was in operation.
Comparison of the Tethyan and Southern
Permian Basin climatic records with the Triassic
succession in the central North Sea indicate a broad
correspondence between wetter climatic phases
and the basinward expansion of the Skagerrak
Formation fluvial systems (Fig. 18). In this frame-
work the Judy and Joanne Sandstone members
(and possibly the Josephine Sandstone Member)
appear to have extended basinwards during epi-
sodes of more frequent humidification across
the region, with the Skagerrak Formation shale
members representing terminal fluvial contraction
during aridification. This would be in keeping
with the evidence of salt crust fabrics and micro-
bial mats within the shale-prone members and
well developed soil profiles and bioturbation
within the sand-prone members. This scenario
contradicts the climatic model suggested by
Goldsmith et  al . (2003), who used palynological
indications of marsh and lacustrine conditions in
the Julius Mudstone Member, together with var-
iations in shale colour, as a guide to water table
conditions and to infer a wetter climate during
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