UNDERSTANDING THE PALEOECOLOGY OF THE CENTRAL VARISCAN MOUNTAINS OF SOUTHERN FRANCE USING PALEOBOTANICAL DATA

The Permo-Carboniferous stratigraphy of Southern France lacks detailed biostratigraphic control and therefore paleoclimate reconstructions are poorly constrained. A fossil-bearing sandstone unit was identified as near the town of Requista in Southern France, and several fossil specimens were recovered. The unit comprises fossiliferous sandstone layers with thin interbedded mudstones, some mudstones were fossiliferous, which contained fossils in some localities. The fossiliferous section lies stratigraphically underneath volcaniclastic ash deposits and overlies a diamictite deposit, indicating a period of tectonic and climatic variability. Recovered specimens included both Calamites and Lepidodendron. The Lepidodendron provides a Carboniferous age for the assemblage. In addition, the fossils indicate deposition in a swamp-like environment, similar to many other Carboniferous deposits regionally, but lacking the usually observed coal like layers. Analysis of recovered fossils, including microfossils, indicate that this area represents an alpine swamp that lacks the larger coal-forming plants of the Carboniferous indicating a slightly colder climate than has been traditionally depicted in the Central Variscan Range. This supports other findings portraying the late Carboniferous to Permian as having a lower global temperature and possible glacial cycles at low latitudes.