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There are some similarities with the scour fills that are described somewhat later this section, because
they show similar properties. The difference is the shape of the bodies. The facies in this section forms
more laterally continuous bodies, while the latter is characterised by more lateral variability.

4.3.2 Parallel laminated units

Description

Straight parallel laminated beds consisting of relatively fine grained material, which is illustrated by
figure C.1 in appendix C. Laminae thickness varies from a few to 15 centimetres. A relatively low amount
of preserved fossil content is observed within these deposits. The southwestern part of Cala Rossa shows
significant units that have parallel laminated bedding.

Interpretation

The parallel lamination can develop in two totally different types of energetic environments. On one side,
the lower flow regime beds can form parallel lamination, with the tendency to form ripples or dunes when
energy increases. On the other side, this type of lamination can be formed by a high energy upper flow
regime. In this case existing dunes will be eroded, so a flat surface will remain to accommodate other
sediment. An increase in energy would potentially become supercritical and will have the possibility to
form antidunes or a scour system.
Outcrop data reveals that stratigraphically the parallel laminated units are in proximity to other low
energetic deposits. For example, most of the outcrops near Cala Rossa show a distinct upward trend.
Starting with massive homogeneous layers, the structure changes to parallel lamination. On top of that,
dunes start to form. This might indicate that the parallel laminations are developed in a transition stage
between no visible lamination and the formation of ripples or dunes.

4.3.3 Undulated lamination and scour fills

Both the undulated lamination and the scour fill facies are described in a single section, as they are in
some cases strongly interrelated.

Description

The undulated lamination shows sinusoidal behaviour, with wavelengths of order of magnitude one to
two metres. They often erode the lower structures, creating an inter-cutting system. Two different scales
of scour fills are observed. The first type consists of very large — up to 20 metres thick — scour fills,
mainly located in the area around Scala Cavallo and further south. The second type of fill is deposited in

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