Charcoalified wood from the cenomanian of gard (Southern France): An insight into early angiosperm palaeoecology

Abstract

The discovery in the Cenomanian (early Late Cretaceous) of Southern France of several localities with abundant charcoal has brought to light several angiosperm wood types. This is the oldest angiosperm wood assemblage discovered yet for Europe. Here we analyse this assemblage, with emphasis on features recognized to be of particular palaeoecological and climatic significance for the Cainozoic according to earlier studies and comparing the inferred results to those from other independent lines of evidence (sedimentology, palynology, isotopic geochemistry, etc.). Vessel diameter and distribution, perforation plates, abundance of vascular tracheids and of septate fibres, presence of diffuse axial parenchyma perhaps should not be used as palaeoecological proxies for the Cretaceous because they do not seem to clearly correlate with other lines of evidence that indicate warm tropical conditions. The abundance of fibre-tracheids fits with the other sources of data, but our results are probably biased by preservation problems. On the contrary, the occurrence of growth-rings, porosity, vessel density, occurrence of vessel groups, occurrence of vasicentric tracheids and of some paratracheal to vasicentric and banded axial parenchyma correlate well with other palaeoclimate indicators. These results show that these features can be used for palaeoclimatological inferences during the early Late Cretaceous