Provenance conclusion of the GdA Fm.

The provenance interpretation of the Grès d'Annot Formation is ambiguous considering this study and other studies contribute with contradictory conclusions, which are based on sedimentological features, petrographical analysis or geochemical data. Mostly, when applying an individual method for the provenance interpretation, it provides convincing provenance evidences. However, if conclusions of all methods are assembled to provide an overall interpretation of provenance, they oppose and enable uncertainty. Nevertheless, an approach of provenance and a determination of the source area is possible when conclusively interpreting the results of this study combined with other studies. Without doubt the paleo-current trend northwards across the entire basin (details, chapter 6.6.), whereby a rotation of the crust is unlikely, which may have rearranged the trend. The bulks of the successions apparently are similar across the basin, whereby even correlation between far distant composite logs are feasible (details, chapter 6.5. and picture 6.5). These logs also show a logical decrease of sediment coarseness when progressing northwards, which is distal. Petrographical analysis of the arkoses suggests that the primary sediment derived from acidic plutonics, lavas and gneisses, most likely an crystalline basement. The south - southeast derived paleo-current trend, together with the petrology, implies an source rock of crystalline basement akin to those who outcrop on Corsica and Sardinia (Figure 4.2a). The conglomerates though must have had an another source rock, since only exposed in the northern region. Most likely they derived as Alpine encroachment of thrust sheets closed into the basin causing layering of a tectonised sedimentary mèlange, which might have fed the deposition system with relatively, for this area, abnormal well rounded and large clasts. Furthermore, if this event also might have had an impact of the heavy-mineral composition in some areas, more than others, is like the alternative of sediment contribution of minor important source areas, uncertain. Alternatively, the differing heavy-mineral ratios might be a natural process, because individual minerals can be transported further distances than others can. However conclusively, the major composition of the arkoses, whether they are from a southern- or northern area, emphasise similar source areas.