Fig. 10

Schematic palaeoenvironmental interpretation of the Cassina beds, deposited in a restricted basin with oxygen-depleted bottom-waters and separated from the open ocean by the shallow-water Salvatore carbonate platform. A diversified fish fauna with various feeding strategies dwelled in the surface waters whereas thin-shelled nodosariid foraminifers temporarily colonized the muddy seafloor under anoxic to suboxic conditions. Platform-related shallow-water benthic taxa were washed into the basin by storms. Plant remains document the presence of emerged areas covered with vegetation. The geometry of the basin can only roughly be inferred. Extensional tectonics has been assumed as a controlling factor for the intra-platform basin but relevant field evidences are missing in the Monte San Giorgio area, where alpine faults and discontinuity of outcrops preclude a detailed reconstruction of the basin to platform transition. Lithological patterns as in Fig. 2. Not to scale