Middle Oxfordian benthic foraminifera from the shelf to the basin in southeastern France. Distribution and environmental control

The aim of this work is to characterize the associations of benthic foraminifera from the shelf to the basin in southeastern France during Middle Oxfordian time. Seven well correlated sections allow the comparison of samples from different but perfectly isochronous environments. A detailed inventory of 94 taxa is given for the Transversarium zone and 4 associations are proposed to characterize respectively the basin, the slope, the outer shelf and the inner shelf. Agglutinated foraminifera, spirillinids and lenticulinids are the main components of the benthic microfauna. The calculation of their percentage allows to estimate the relative bathymetry. According to recent works on foraminifer ecology, the main controlling factors seem to be food supply and competition, The peculiar microfauna from Beauvoisin is explained by a localized chemosynthetic primary production. This is consistent with the previous hypothesis concerning the origin of the pseudobioherms which characterize this locality.