Page 81 - MSc_thesis_R A Kil

8 Conclusions

1. The island of Favignana, located a few kilometres off the coast of western Sicily (Italy), is the island
of the Aegadian archipelago that shows the largest development of Lower Pleistocene sediments.
The mountainous structures of all three islands are the result of the Alpine orogeny and subsequent
uplift due to strike-slip movement, and consist mainly of limestone. Favignana is unique because of
its relatively low-relief eastern part, where quarrying of the calcarenite rock has been going on for
centuries.

2. The detailed sedimentological descriptions in the field and microfacies analysis of the eastern
Favignana calcarenite indicates a typical foramol grain association. These bioclastic carbonate-
rich sediments have been interpreted as generated in a high-energy dominated, open shelf, cool-
water/temperate environment.

3. Storm-related events caused the bioclastic sediment to be either 1) transported from a productive
platform; or 2) reworked and deposited at the same location. The dominance of northwestern to
northern winds in this part of the Mediterranean introduced a predominant south to southeast
transport direction in the sedimentary structures. The northeastern part of Favignana is influenced
by storms from the north, and therefore shows a system that builds out to the south, while the rest
of the complex predominantly progrades to the southeast.

4. Eastern Favignana is unique because of the progradation towards the mainland of Sicily. Comparable
deposits in the Mediterranean show calcarenites deposited on the shelf of a large landmass. The
habitat of the organisms was at the same location, and storm events caused the skeletal material to
be reworked and deposited. The eastern Favignana calcarenite is interpreted as being deposited
in a submarine environment, possibly on the shelf of an already existing channel-like depression
between the older mountainous structures of Favignana and Levanzo.

5. A wide range of sedimentary structures are observed in the field, indicating a varying supply of both
sediment and energy. Apart from the main progradation towards the southeast, a system that scours
into the earlier deposited sediments is recognised. Scours of up to 20 metres provided a highway for
sediment to be transported to the lobes of the system. Scour fills show thick homogeneous units.
Locally the amount of energy was high enough to develop critical flow conditions. As a result,

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