Southern Region Chalk Group Lithostratigraphy: Sussex lithostratigraphy of Mortimore (1986a) - Haven Brow Beds

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The Haven Brow Beds, c. 34 m thick in Sussex, are marked by the Michel Dean Flint at the base and the lowest of the Buckle Marls at the top (Mortimore, 1986a). Soft, pure white flinty chalk is characteristic, some of the flints being conspicuous markers and named (in ascending order) the Baily's Hill Flint, Flat Hill Flint, Brasspoint Flint, Rough Brow Flint, Short Brow Flint and the Exceat Flint (Mortimore, 1986a). The Michel Dean Flint, Baily's Hill Flint and Flat Hill Flint form a closely spaced group near the base of the Haven Brow Beds, and are associated with acmes of the inoceramid bivalve Cladoceramus undulatoplicatus, which is locally preserved in the flints (Mortimore, 1986a)

The fauna of the Haven Brow Beds is more diverse and abundant than the underlying Cuckmere Beds. Apart from the acmes of the distinctively shaped Cladoceramus undulatoplicatus near the base, the echinoids Conulus aff. albogalerus, Micraster coranguinum and Micraster (Isomicraster) gibbus become common, and occur with local acmes of the terebratulid brachiopod Gibbithyris ellipsoidalis and the inoceramid bivalve Cordiceramus cordiformis (Mortimore, 1986a).

Macrofossil Biozonation: upper M. coranguinum Zone

Correlation: see Correlation with other Southern Region Chalk Group classifications

see Correlation with other UK Chalk Group successions

References[edit]

MORTIMORE, R N.1986a. Stratigraphy of the Upper Cretaceous White Chalk of Sussex. Proceedings of the Geologists' Association, Vol. 97(2), 97-139.

See: flint, Michel Dean Flint, Flat Hill Flint, Cladoceramus undulatoplicatus acmes