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(A)
(B)
Fining upward
100
100
Top
Top
FM
90
90
FM
FM
80
80
70
70
FM
FM
FM
60
60
FM
50
50
40
40
FM
30
30
20
20
FM
FM
10
10
0 cm
Base
0 cm
Base
Fig. 16. Facies association FA8: Tidal-fluvial channel deposits. A) Basal conglomerates (channel-bottom lags) overlain by
fining-upward and cleaning-upward, cross-bedded, medium-grained to fine-grained sandstone. B) Single and compound
fluid-mud layers at the base of tidal-fluvial channel succession. Fluid-muds (FM) are commonly overlain by fining-upward,
cross-bedded, medium to fine-grained sandstone showing rip-up mud clasts. Notice the sparse bioturbation. Examples
taken from reservoir zone Tilje 5.1 (T5.1).
2009). FA8 shows dominant unidirectional current-
generated sedimentary structures produced by the
migration of dunes; this, coupled with the presence
of conglomerates and coarse-grained sandstones, is
suggestive of a high-energy depositional setting.
Locally, bipolar ripple-cross lamination and herring-
bone cross-stratification and abundant mudstones
showing thick-thin alternations are indicative of a
tidal influence. The low-diversity trace-fossil assem-
blage dominated by vertical burrows suggests a
stressed environment with brackish-water condi-
tions. All of these characteristics indicate that FA8
was deposited in a tidal-fluvial channel setting.
Given the expected downstream fining of bed mate-
rial in deltaic systems (Dalrymple & Choi, 2007),
the  local presence of conglomeratic facies suggests
that deposition occurred in a relatively proximal
location, perhaps near the limit of tidal and brackish
water influence during low river flow.
Facies association 9 (FA9): Heterolithic
tidal bars
FA9 (Fig. 17) is dominated by mixed sandstone-
mudstone heterolithics that are thin to medium
bedded. Overall, FA9 successions (up to 4 m
to  5 m thick) show an upward thinning of the
interbedded sandstone and mudstone layers.
Locally, sharp-based, stacked upward-sandier
intervals are present. Rare upward-coarsening
heterolithic successions (2 m to 3 m thick) are
visible. The base of each FA9 succession is char-
acterised by sharp-based, lenticularly-bedded,
mudstone-dominated heterolithics (F5.) and
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