Southern Region Chalk Group Lithostratigraphy: Bristow et al. (1997) - Studland Chalk

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The Studland Chalk (stratotype: Studland Bay [SZ 055 825 to SZ 045 824] ) was defined by Gale et al. (1987), and comprises soft, marl-free chalk with large, irregularly developed flints (Bristow et al., 1997). Up to 23 m are preserved beneath the Tertiary erosion surface in the Isle of Wight, although coeval chalk in central Dorset was included in the top of the Portsdown Chalk by Bristow et al. (1997) because no mappable feature occurs to separate the two units. In coastal sections, the base of the Studland Chalk is immediately above a bed of marly chalk with an included marl seam, marking the top of the Portsdown Chalk sensu Gale et al. (1987) (Gale, unpublished data). The Studland Chalk is characterised by pink-shelled oysters, and similarly preserved brachiopods, especially Magas chitoniformis and Cretirhynchia woodwardi (Bristow et al., 1997).

Macrofossil Biozonation: B. mucronata Zone (pars)

Correlation: see Correlation with other Southern Region successions

see Correlation with other UK successions

References[edit]

BRISTOW, C. R., MORTIMORE, R. N. & WOOD, C. J. 1997. Lithostratigraphy for mapping the Chalk of southern England. Proceedings of the Geologists' Association, Vol. 108, 293-315.

GALE, A S, WOOD, C J & BROMLEY, R G. 1987. The lithostratigraphy and marker bed correlation of the White Chalk (late Cenomanian-Campanian) in southern England. Mesozoic Research, Vol. 1, 107-118.

See: Portsdown Chalk (Bristow et al., 1997), marl, flint