Southern Province Chalk nomenclature - White Chalk Subgroup: Upper Campanian and Maastrichtian Chalk in the Transitional Province

These chalks do not fit within the formal framework applied to the Southern Province and no attempt has been made to correlate these informal units with the upper part of the Flamborough Chalk Formation nor the Rowe Formation of the Northern Province with which they broadly share some characteristics and age. The Upper Campanian chalks are informally designated as the ‘Norwich Chalk’ as much of the succession has been long studied in numerous pits around Norwich. Peake and Hancock (1961, 1970) split this succession into a number of named units that were tentatively delimited during the survey of the Norwich Sheet 161 and published as a diagram within the memoir (Cox et al., 1989). The Maastrichtian chalks have become known informally as the Trimmingham Chalk and are described in glacially deformed ‘erratics’ (of considerable size) on the coast between Overstrand and Trimmingham. Again a number of units were given names. Both sets of informal names were given member status in Johansen and Surlyk (1990). All of the succession was investigated in the Trunch Borehole (TG23SE 8 [TG 2933 3455]) that was published in the Great Yarmouth Memoir (Arthurton et al., 1994). No firm conclusion has been reached regarding formal nomenclature for these beds since their distribution under a thick Quaternary cover has not been determined. It is recommended that reference to these units be made informally using the Norwich and Trimmingham terms until such time as they can be formally attributed. The development of the terminology applied to this succession is given in Figure 5c.