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

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The New Pit Chalk, typically 40-50 m thick, mostly equates with the New Pit Chalk of Mortimore (1986a), comprising massively bedded, sparsely flinty chalk with regularly spaced marl seams and marl wisps. However, following the stratigraphical revisions proposed by Mortimore & Pomerol (1996), the base of the New Pit Chalk is downwardly revised to be coincident with the Gun Gardens Main Marl, and the top of the unit is revised downwards to the base of the lowest nodular chalks of the Lewes Nodular Chalk of Bristow et al. (1997). As so defined, the New Pit Chalk includes the Glynde Beds of Mortimore (1986a), which the latter author assigned to the base of the Lewes Chalk.

In the Isle of Wight and south Dorset, the equivalent of the higher part of the New Pit Chalk Member, from below the New Pit Marls to the basal Lewes Nodular Chalk Member, is condensed into the Spurious Chalk Rock (Gale, 1996). In some parts of south Dorset (eg. Weymouth district) the equivalent of the New Pit Chalk Member is hard, nodular chalk, mapped by the BGS as Holywell Nodular Chalk Member.

Macrofossil Biozonation: upper Mytiloides spp. Zone & T. lata 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.

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 & POMEROL, B.1996. A revision of Turonian litho- and biostratigraphy in the Anglo-Paris Basin. Mitteilungen aus dem Geologisch-Paläontologischen Institut der Universitat Hamburg, Vol. 77, 423-441.

See: New Pit Chalk (Mortimore, 1986a), flint, marl, Gun Gardens Main Marl, Lewes Nodular Chalk (Bristow et al., 1997), Glynde Beds, Lewes Chalk (Mortimore, 1986a), Spurious Chalk Rock.