Evidence for a shallowing event in the Upper Turonian (Cretaceous) Mytiloides scupini Zone of northern Germany

Abstract

Based on the evidence of a regression in the Late Turonian (Cretaceous) scupini Zone of the Münsterland Cretaceous Basin (Westphalia), the exposures Nettlingen and Gross-Flothe are investigated in order to discover whether or not a comparable event can be observed in Lower Saxony. The lithological and faunal investigation of the two localities show this to be the case. This regressive event is interpreted to be the expression of a sequence boundary, separating two 3rd order sea-level cycles. The lower sequence, the base of which is located above the main Hyphantoceras Event in the middle Late Turonian of northern Germany, is termed the "flexuosum Sequence". The sequence above the sequence boundary, which ranges into the Lower Coniacian Cremnoceramus deformis Zone, spans approximately the reported range of Didymotis costatus. It is, therefore, named the "Didymotis Sequence". It can be shown that the observed sequence boundary can also be recognized in Spain, southern England, Poland and the Czech Republic.