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6c
Heterolithic
ripple cross-
laminated
sandstone
with wavy-
bedding
Sharply inter-laminated
mudstone and
sandstone; very-fine
to very coarse-grained;
continuous dominant
unidirectional and sub-
dominant bidirectional
ripple-laminae
draped by laminated/
structureless siltstone
and mudstones;
distinct overall
coarsening-up trend
Sandstone bed
thickness < 30 cm;
siltstone and
mudstone beds
< 5 mm, lateral
extent from 100 m
up to 3 km
Fine member:
moderate to high
intensity (3 to
6). Dominant
ichnofabrics:
Tei,
Ph, Ro, Op, Pl, Pa,
Th, Sk, Ar, ?As
.
Coarse member:
low to moderate
intensity (1 to
3). Dominant
ichnofabrics:
Ph,
Pl, Pa
.
Deposition of
sand as ripples
during repeating
current activity
and subsequent
deposition of mud
from suspension
during slack water
stage; secondary
wave modification
1A of fluvial-tidal transition
2A of tidal inclined
heterolithic strata
2B of tidal inclined
heterolithic strata
3A of tidal channel
infill
3B of tidal channel
infill
3C of tidal channel
infill
3D of tidal channel
infill
5A of mixed tide- and
wave-influenced
heterolithic delta
5C of mixed tide- and
wave-influenced
heterolithic delta
7A of wave-dominated
open-marine
7B (rare) of wave-dominated
open-marine
1B
†
of fluvial-tidal transition
1C
†
of fluvial-tidal transition
7
Hummocky
and swaley
cross-
stratified
sandstone
Clean; well sorted;
very fine-grained
to fine-grained;
low-angle curving
cross-lamination;
wavelength 10 to 20 cm
Sharp lower and upper
boundaries; bed
thickness 5 to 30 cm,
lateral extent > 100 m
Unbioturbated (0
to 1); occasional
secondary
Pl
and/or
Co
; low to
moderate intensity
(1 to 3)
Deposition by storms
in lower shoreface
and pro-delta
environment
2C of tidal inclined
heterolithic strata
4A
†
of wave-dominated
shoreface
4B
†
of wave-dominated
shoreface
5B
†
of mixed tide- and
wave-influenced
heterolithic delta
6A
†
of brackish-marine
embayment
7B
†
of wave-dominated
open-marine
(
Continued
)
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