Revision of the 'Late Jurassic' stratigraphy of the Dutch Central North Sea Graben

Abstract

The 'Late Jurasic' stratigraphy of the Dutch Central North Sea Graben is revised. The sediments, ranging in age from Callovian to Ryazanian, are grouped in two lithological units: the mainly non-marine Central Graben Group (with Lower Graben Sand, Middle Graben Shale, Upper Graben Sand, Puzzle Hole, and Delfland formations) and the distinct marine Scruff Group (with Kimmeridge Clay, Scruff Greensand, and Clay Deep formations). The latter two formations are new and are introduced formally. Basic palynological and micropaleontological data are included to support age assignments of various formations. Several log correlations, range charts, distribution maps, facies maps and seismic sections are given to illustrate the stratigraphic framework. Finally, a synopsis of the geological history is presented, with special attention to sea-level changes and ensuing coastal developments, illustrating the relationships with the Danish and Norwegian sectors.