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

From Earthwise
Jump to navigation Jump to search

The Castle Hill Beds, c. 12 m thick locally in Sussex, are marked by the upper Castle Hill Marl at the base, and the Lancing Flint at the top (Mortimore, 1986a). The succession comprises very soft, pure white chalk, with 11 to 13 conspicuous, large, nodular flints (Mortimore, 1986a). Marls locally occur at the base of the succession in Wiltshire, and are named the Pepperbox Marls (Mortimore, 1986a &b).

The fauna of the Castle Hill Beds is dominated by echinoids, particularly the large Echinocorys morphotype of Gaster (1924) and Hagenowia blackmorei in the lower part, and the small Echinocorys morphotype of Gaster (1924) in the higher part (Mortimore, 1986a). In Wiltshire, the belemnite Belemnitella locally occurs in this interval (Bailey et al., 1983).

Macrofossil Biozonation: lower G. quadrata Zone, Hagenowia Horizon & basal A. cretaceus Subzone

Correlation: see Correlation with other Southern Region Chalk Group classifications

see Correlation with other UK Chalk Group successions

References[edit]

BAILEY, H W, GALE, A S, MORTIMORE, R N, SWIECICKI, A & WOOD, C J. 1983. The Coniacian-Maastrichtian stages of the United Kingdom, with particular reference to southern England. Newsletters on stratigraphy, Vol. 12, 29-42

GASTER, C T A. 1924. The Chalk of the Worthing District, Sussex. Proceedings of the Geologists' Association, Vol. 35, p. 89-110.

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

MORTIMORE, R N. 1986b. Controls on Upper Cretaceous sedimentation in the South Downs, with particular reference to flint distribution, in SIEVEKING, G de C & HART, M B. The scientific study of flint and chert. (London: Cambs. Univ. Press.)

See: flint, marl