Aptian lithostratigraphy and biostratigraphy (foraminifera) of block 49 in the southern North Sea (U.K. sector)

Abstract. Strata of Aptian age in block 49 of the southern North Sea (U.K.) are reviewed in terms of lithostratigraphy, wireline log character and foraminiferal fauna. In some boreholes, the basal part of the Middle Holland Shale Member is interpreted as Late Aptian in age while the Lower Holland Marl Member is interpreted as Late to Early Aptian in age. The foraminiferal biostratigraphy of the Aptian strata in the designated reference borehole, 49/25-1, for the Dutch lithostratigraphical scheme in the U.K. southern North Sea is discussed briefly.