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heterolithic, characterised by a very strong bi-
modal grain-size distribution. Sandstones in the
studied succession are quartz-dominated. The feld-
spar content is generally low, but estimated up to
about 20% in the most feldspar-rich sandstone
beds. Mica is generally abundant. Chlorite and
glauconite are also abundant at certain stratigraph-
ical levels (Fig. 6). The quartz and feldspar grains
are generally subrounded to rounded, thus indicat-
ing extensive reworking. Some of the conglomer-
atic beds include abundant angular quartz and
quartzite grains, probably delivered directly as first
generation detritus from basement rocks. Examples
of distinct fluvial sedimentary structures are sparse
due to overprinting by tidal reworking.
The genetically related lithofacies are subdi-
vided into seven facies association groups (Table 2).
These facies associations groups are the building
blocks of architectural elements (Table 3) and
genetic successions in the Neill Klinter Group. The
depositional architecture of the Neill Klinter Group
is summarised in Fig. 7 and localities in Fig. 4.
mudstones rich in macroplant fossils (Dam & Surlyk,
1992; this study) into structureless siltstones and
cross-stratified sandstones containing marine body
fossils, micro fossils and trace fossils (for example,
Diplocraterion parallelum
; Fig. 8A, i-iii). In light
of these marine indicators, the terrestrial palyno-
morph assemblage is suggested to be allochtonous
(Koppelhus & Dam, 2003). The up to 15 to 20 m thick
upward-fining sandy succession above the TS1 is
composed of lower shoreface-foreshore sandstone
facies association FA4b (Table 2) and sharply over-
lain by thinly laminated silty shales. The sandstones
of facies association FA4b are thinning northward
and are not present at localities N1 to 4, where the
corresponding stratigraphic level is an up to 25 m
thick black shale unit rich in terrestrial and brack-
ish-water palynomorphs and microfossils with
minor amounts of marine specimens (this study).
The shale unit is composed of brackish-marine
embayment facies associations (FA6a and 6c;
Table 2) and sharply overlies an up to 10 m thick
light-coloured and poorly sorted quartz-rich sand-
stone unit. The top of the shale unit is marked by a
few metres-thick upward-coarsening facies transi-
tion into sandy heterolithic strata (Fig. 8B).
Bounding surfaces, allostratigraphic units,
architectural elements
Lower stratigraphical compartment of the
Neill Klinter Group
Interpretation: Allostratigraphic unit 1
Based on the change in facies and fossil content,
the basal unconformity of allostratigraphic unit 1
is interpreted as a basinwide marine transgressive
ravinement surface, TS1, separating alluvial plain
and lacustrine strata of the Kap Stewart Group from
overlying shallow marine strata of the Neill Klinter
Group (Figs 2 and 7). Above TS1, fossiliferous
marine sandstones of the lower shoreface to fore-
shore sandstone facies association (FA4b) define the
retrogradational architectural element shoreface-
foreshore sandstone SHFS (Fig. 8A; Table 3) in the
south. In the north, the shales of brackish-marine
embayment facies associations (FA6a and 6c) consti-
tute the contemporaneous wave-influenced brack-
ish embayment architectural element, WIBE (Fig. 8B;
Table 3). The along-strike shift in facies reflects bas-
inward (south and west) increasing water depths,
while the change in palynomorph fauna suggests a
northward decrease in salinity. Combined, the
south to north transition from SHFS to WIBE archi-
tectural element is interpreted to record an overall
retrogradational depositional architecture.
The flooding surface FSa (Fig. 7) on top of the
allostratigraphic unit 1 marks the drowning of the
At all localities, the lower compartment is bounded at
its base by a transgressive surface (TS1) and topped
by a combined subaerial unconformity and trans-
gressive surface (SU1/TS3; Fig. 7). The compart-
ment is divided into i) retrogradational, ii)
progradational to aggradational and iii) retrogra-
dational to progradational architectural elements
which comprise allostratigraphic units 1 to 3.
Allostratigraphic unit 1
Description: Retrogradational architectural
elements
The base of the Neill Klinter Group was defined
by Dam & Surlyk (1998) as a thin lag conglomerate
bed with fragmented body fossils and quartzite
pebbles. In this study the same boundary is
referred to TS1, defining the base of the allostrati-
graphic unit 1.
Along the localities S1 to 8 (Fig. 7) the TS1 bound-
ary marks a lithofacies change from alternating fine-
grained to coarse-grained, wave ripple-laminated to
cross-stratified sandstones and black laminated
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