Southern Region Chalk Group Lithostratigraphy: The North Downs (Robinson, 1986) - Ramsgate Chalk Formation: Difference between revisions
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The Ramsgate Formation (composite stratotypes: Langdon Stairs [TR 343 425], St. Margarets Bay [TR 371 446] to Kingsdown Rifle Range [TR 380 473], Pegwell [TR 368 640], Joss Bay [TR 398 702], White Ness [TR 396 710], and Foreness Point [TR 384 716]) has a minimum composite thickness of 119.3 m. Marls occur through the hard, nodular lower beds, and in the lower part of the soft, flinty, non-nodular chalk above, but are practically absent from the upper part of the formation, where flints are locally more sparse and weakly developed (Robinson, 1986). The base of the formation is the base of the Crab Bay Marl; there is no upper boundary to the formation, which is truncated by the Tertiary erosion surface (Robinson, 1986). The formation is divided into three members, in ascending order, the St Margaret's Member, the Broadstairs Member and the Margate Member (Robinson, 1986). | The Ramsgate Formation (composite stratotypes: Langdon Stairs [TR 343 425], St. Margarets Bay [TR 371 446] to Kingsdown Rifle Range [TR 380 473], Pegwell [TR 368 640], Joss Bay [TR 398 702], White Ness [TR 396 710], and Foreness Point [TR 384 716]) has a minimum composite thickness of 119.3 m. Marls occur through the hard, nodular lower beds, and in the lower part of the soft, flinty, non-nodular chalk above, but are practically absent from the upper part of the formation, where flints are locally more sparse and weakly developed (Robinson, 1986). The base of the formation is the base of the Crab Bay Marl; there is no upper boundary to the formation, which is truncated by the Tertiary erosion surface (Robinson, 1986). The formation is divided into three members, in ascending order, the St Margaret's Member, the Broadstairs Member and the Margate Member (Robinson, 1986). | ||
Latest revision as of 12:35, 7 October 2013
The Ramsgate Formation (composite stratotypes: Langdon Stairs [TR 343 425], St. Margarets Bay [TR 371 446] to Kingsdown Rifle Range [TR 380 473], Pegwell [TR 368 640], Joss Bay [TR 398 702], White Ness [TR 396 710], and Foreness Point [TR 384 716]) has a minimum composite thickness of 119.3 m. Marls occur through the hard, nodular lower beds, and in the lower part of the soft, flinty, non-nodular chalk above, but are practically absent from the upper part of the formation, where flints are locally more sparse and weakly developed (Robinson, 1986). The base of the formation is the base of the Crab Bay Marl; there is no upper boundary to the formation, which is truncated by the Tertiary erosion surface (Robinson, 1986). The formation is divided into three members, in ascending order, the St Margaret's Member, the Broadstairs Member and the Margate Member (Robinson, 1986).
Macrofossil Biozonation: T. lata Zone (pars), S. plana Zone, M. cortestudinarium Zone, M. coranguinum Zone, U. socialis Zone, M. testudinarius Zone & O. pilula Zone (Robinson, 1986)
Correlation: see Correlation with other lithostratigraphical schemes for the Southern Region
see Correlation with other UK regions
References
ROBINSON, N D.1986. Lithostratigraphy of the Chalk Group of the North Downs, southeast England. Proceedings of the Geologists' Association, Vol. 97, 141-170.
See: marl, flint, St. Margarets Member, Broadstairs Member, Margate Member