| Computer Code: |
UCK |
Preferred Map Code: |
UCk |
| Status Code: |
Full |
| Age range: |
Turonian Age (KT)
— Maastrichtian Age (KM) |
| Lithological Description: |
White chalks (microporous coccolithic limestone) with beds of flint, nodular chalks, hardgrounds and marl seams. Note: No type section has been established. See Chalk Rock for stratotypes of base of Upper Chalk.
Name remains in informal use but generally regarded as obsolete onshore. |
| Definition of Lower Boundary: |
At base of Chalk Rock, a hard basal unit. (Conventionally also taken at base of Holaster planus Zone). |
| Definition of Upper Boundary: |
In mainland Britain this is an unconformity overlain by post-Cretaceous formations. |
| Thickness: |
Up to 60 m preserved in the Hitchin district, more than 300 m in parts of Norfolk. |
| Geographical Limits: |
As used here: The Chilterns, extending to South Norfolk and Suffolk: i.e. area of "Anglo-Brabant Massif". Definition breaks down where Chalk Rock disappears. Approximates to the "Transitional Province" of Mortimore (1983). |
| Parent Unit: |
Chalk Group (CK)
|
| Previous Name(s): |
Chalk, Undivided, Upper (Now Upper Chalk Formation) [Obsolete Name and Code: Use UCK]
(-4948)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| none recorded or not applicable |
| Reference(s): |
| Mortimore, R N. 1983. The stratigraphy and sedimentation of the Turonian-Campanian in the Southern Province of England. Zitteliana, Vol.10, 27-41. |
| Wood, C J and Smith, E G. 1978. Lithostratigraphical classification of the Chalk in North Yorkshire, Humberside and Lincolnshire. Proceedings of the Yorkshire Geological Society, Vol. 42, 263-287. |
| Jukes-Browne, A J and Hill, W. 1904. The Cretaceous Rocks of Britain, Vol.3. The Upper Chalk of England. Memoir of the Geological Survey of Great Britain. |
| Waters, C N, Smith, K, Hopson, P M, Wilson, D, Bridge, D M, Carney, J N, Cooper, A H, Crofts, R G, Ellison, R A, Mathers, S J, Moorlock, B S P, Scrivener, R C, McMillan, A A, Ambrose, K, Barclay, W J, and Barron, A J M. 2007. Stratigraphical Chart of the United Kingdom: Southern Britain. British Geological Survey, 1 poster. |
| Jukes-Browne, A J and Hill, W. 1903 The Cretaceous Rocks of Britain, Vol.2. The Lower and Middle Chalk of England. Memoir of the Geological Survey of Great Britain. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E220
E221
E222
E204
E205
E206
E238
E239
E240
E266
E282
E284
E298
E299
E327
E314
E283
E269
E237
E064
E065
E072
E147
E161
E160
E146
E159
E162
E132
E148
E300
E175
E188
E189
E190
E207
E223
E241
E253
E254
E255
E257
E258
E259
E268
E131
E267
E270
E271
E272
E273
E274
E281
E341
E342
E343
|
