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Geology Departments, Royal School of Mines, Imperial College London, SW7 2BP, UK
Sequence stratigraphic analysis of the Aquitaine, Münster and Paris Basins has shown that many of the major discontinuities found can be traced with good biostratigraphic confidence between the basins, and through a variety of sedimentary, tectonic and palaeobiogeographic regimes. Up to five sequence boundaries appear to be synchronous between the basins when account is taken of the biostratigraphic shortcomings. An extra sequence boundary near the Lower-Middle Cenomanian boundary in the Münster Basin may be a tectonic disruption as all evidence for this relative sea-level fall is from the northern, active margin of the basin, where it is associated with mass flow deposits. Notable features are the absence of lowstand deposits in these epieric, hemipelagic settings and the expression of sequence boundaries as hardgrounds. Multiple transgressive surfaces are common in deeper water settings, and surfaces of maximum flooding are very poorly developed. However, deep water deposits do preserve more accurate evidence of sea-level change, due to increased lithological and biostratigraphical completeness and fewer controls on sedimentation.
