Page 52 - MSc_thesis_R A Kil

4.4 Stratigraphic logs and facies distribution

The micro- and macrofacies together with stratigraphic logs have been combined and the result is shown
in figure 4.10, which represents a panel crossing through the eastern part of Favignana. A correction for
elevation is applied, making it easier to correlate various depositional environments across the logs. The
logs show primary sedimentary structures, fossil content, and an attempt to illustrate grain size variation.
These data were then used to establish a conceptual geological model by correlating the logs as the basis
for a 3D facies distribution.
A different way of visualising the fieldwork results is a map with pie charts (figure 4.11). Each pie chart
shows the relative distribution of facies at a particular pseudo-well location. In order to distinguish
larger outcrops from smaller ones, the pie charts are scaled to the thickness of the outcrop where the
measurements were taken. Unlike the detailed stratigraphic logs presented earlier, all fieldwork locations
are included (see figure D.1 in appendix D), so observations from a distance and photographs are presented
here as well. Again, the map will be useful in a later stage when the conceptual model is created.

4.5 Palaeo-transport directions

Orientations of foresets, propagating dune beds, undulations and scour geometry are all indicators of
the direction of the flow that deposited such structures. Other sedimentary structures, like as massive
beds or parallel lamination makes extracting palaeo-directions difficult. Where possible, palaeotransport
directions were obtained in the field (figure 4.12). This information can be useful when establishing a
conceptual geological model of the Favignana calcarenite.
Two main transport directions can be inferred from the data. The main system seems to build out
to the southeast, while there is a secondary main direction to the south-southeast. These directions
are good indicators when revealing the sedimentary history of the island. Moreover, the data indicate
that the eastern part of Favignana can be split up in roughly two regions with their own characteristic
palaeo-transport directions. The majority of the island — from Favignana town to Cala Azzurra — shows
a dominant direction to the southeast. A considerably smaller part, concentrated around Cala Rossa and
Bue Marino, has recorded transport to the south.
To a minor extent other transport directions are found, especially in the eastern part of the fieldwork
area. They are indicated with the smaller arrows and show transport to — on average — the north.

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