Eustatic, tectonic and climatic controls on an early syn-rift mixed-energy delta, Tilje Formation (Early Jurassic, Smørbukk field, offshore mid-Norway) - From Depositional Systems to Sedimentary Successions on the Norwegian Continental Margin - page 348

Table 1. ( Continued )

Sedimentary
Structures Facies Subfacies Grain size / description Thickness BI and trace fossils Interpretation

F6.3. Disturbed Hetero-
lithics

Fine to very-fine sand
grain size in mud-
dominated and or mixed
heterolithics. Trace fos-
sils cross-cut each other.
The colour of the beds
is dark grey mudstone
with light grey sand-
stone lenses. Associated
with F5.2.2 and F5.3.2
(see Table 2).

20 to 40 cm
thick

Parallel lamina-
tion, synaere-
sis cracks and
ripple cross-
lamination are
locally visible.

BI 4 to 5. Common to
abundant. High-
diversity. Proximal
expressions of the
Cruziana Ichno-
facies Planolites,
Palaeophycus,
Chondrites , Rosselia ,
Rhyzocoralium , Dip-
locraterion , Cylindrich-
nus , Teichichnus , and
rare Thalassinoides and
Phoebichnus .

In association with current gen-
erated heterolithics 5.2.1. Low
energy and relatively slow tidal
currents. Moderate intensity
trace-fossil suite, and moderate
to high diversity suggest low to
moderate energy (tidal cur-
rents) subjected to chemical and
physical variations.

F6.4. Light grey
homogenised
sandstone

Silty, Very fine to fine-
grained light grey
sandstone. Barely visible
bedding. Overlap of
trace fossils. Discontinu-
ous mudstone and sand-
stone lenses. Locally
nodular with calcite
cement.

Up to 30 cm Discontinu-

ous parallel
lamination.

BI 5 to 6. Abundant to
complete. High-diversity.
Proximal expressions of
the Cruziana Ichnofa-
cies. Small to large-scale
Planolites , Palaeo-
phycus , Cylindrichnus ,
Rosselia , Ophiomorpha
Skolithos, Thalassinoi-
des , and less common
Diplocraterion and
Rhizocorallium .

Homogenisation and destruc-
tion of the original bedding
and structures by syn- and/or
post-depositional bioturbation.
Transitions from suspended
sediment settling to shifting
substrate conditions under
moderate to higher energy.

F6.5. Rooted sandstone Very fine-grained to silty

sandstone. Barely visible
bedding and internal
lamination. Small organic
lenses locally present
toward the top of these
units. Mottled aspect.

Up to 40 cm Parallel lamina-

tion locally
visible

BI 5 to 6. Abundant to
complete. Low diver-
sity. Small plant root-
traces showing bifur-
cated endings, delicate
Skolithos and Ophio-
morpha .

Immature palaeo-soil. Low-energy
setting with salt water influence.

Facies 7 (F7):
Pinstripe-
laminated
mudstones

No subdivisions Sand : mud ratios bet-

ween 10 : 90 and 0 : 100.
Silt-clay dominated.
Sandstones are very
fine-grained, sharp based,
showing normal grading
into siltstone.

Sandstone
lenses
0.5 cm to
1.5 cm;
mudstone
layers
0.5 cm to
3 cm

Pinstripe bed-
ding. Parallel
lamination and
ripple cross-
lamination
occur locally,
showing bipo-
lar ripple cross-
lamination.

BI 0 to 2. Sparse to
uncommon. Mm-scale
burrows like Chondrites
and rare Planolites .

Low-energy conditions. Low tidal
velocities or a scarcity of sand.