(a) Photograph to the west of the sub-site R located in the Bifurcatis zone (Late Oxfordian) and its interpreted drawing (see Fig. 2 for location). (b) Stratigraphic log showing sub-vertically stacked carbonate lenses interbedded with nodules-rich marls. The basal carbonate lens displays a brecciated facies dominated by veins yielding mineralizations and displaying a jigsaw-like structure. (c) Detailed photograph to the north showing the left view of the sub-site R. The carbonate lenses are laterally passing to micritic beds of carbonates. The top of the edifice is characterized by a dm-thich oxidized crust (see Fig. 6)