Early Palaeogene stratigraphy of a cored borehole at Hales, Norfolk

Abstract

The Hales Borehole, located between Lowestoft and Norwich, proved adominantly argillaceous sequence of early Palaeogene strata similar to that recently reported fromt he Ormesby Borehole in the Great Yarmouth area. It demonstrates that the late Palaeocene and early Eocene mudstone facies of the southern North Sea area extend into south Norfolk, without substantial change. The absence of facies typical of the Woolwich & Reading Beds in both boreholes indicates that a substantial non-sequence is present, with early representatives of the London Clay transgression resting directly on mudstone equivalents of the Thanet Formation. Magnetostratigraphical analysis of the Hales core has provided an opportunity to corroborate the record obtained from the Ormesby Borehole. In particular, it has confirmed the presence of a normal polarity zone, ascribed to Chron C26N, within the Thanet sequence.