Eustatic sea level and depth of a Late Cretaceous epicontinental sea: an example from NW Europe

Abstract

The claim that the Late Cretaceous (and more specifically the Campanian-Maastrichtian) global sea Ievel was considerably higher than that of today is partly based on the assumption that one can recognize areas which were tectonically immobile from the Cretaceous onwards. Careful examination of some of these regions in NW Europe suggests, however, that differential (inverse) warping and tilting during and/or since the Cretaceous has invalidated their use as reliable gauges for Late Cretaceous high stands. In addition, the original depth of Late Cretaceous epicontinental seas may have been much shallower than generally assumed. In the literature it is frequently suggested that the NW European flint-bearing chalk was deposited at a depth of 100 to 300 m or more. But this study shows that, for example, the Late Campanian and Maastrichtian flint-bearing chalk in the Hautes Fagnes area of NE Belgium accumulated at a depth of less than 45 to 65 m, matching the Modern deposition of coccolith ooze in the Caribbean Belize Lagoon at depths of less than 40m at places.