Quantitative estimates of calcareous nannofossil changes across the Plenus Marls (latest Cenomanian), Dover, England: implications for the generation of the Cenomanian-Turonian Boundary Event

Quantitative data on absolute abundance and diversity of nannofossils, insoluble residues, δ13C and δ18O from the top Abbots Cliff Chalk, through the Plenus Marls and into the Melbourn Rock at Dover, England suggest, contrary to most previous interpretations, that: (1) The Cenomanian-Turonian Boundary Event was initiated by a sharp fall in sea level which produced the sub-plenus erosion surface, followed by a gradual recovery over 100 000 years...