Chronostratigraphy of the Chalk Group - Santonian Stage

From Earthwise
Jump to navigation Jump to search


The Santonian stage was first defined by Coquand (1857), and presumably named after the village of Saintes in SW France (Lamolda & Hancock, 1996).

Definition of base of stage[edit]

The lowest occurrence of the inoceramid bivalve Cladoceramus undulatoplicatus (Lamolda & Hancock, 1996).

Constituent Chalk Group lithostratigraphical units in the UK[edit]

Integrated southern England Chalk Group lithostratigraphy: Seaford Chalk Formation (pars) and Newhaven Chalk Formation (pars)

Northern England: Flamborough Chalk Formation (pars)

East Anglia: Upper Chalk (pars)

N. Ireland: Cloghfin Sponge Beds Member, Galboly Chalk Member, Cloghastucan Chalk Member

North Sea: Mackerel Formation (pars)

Constituent macrofossil biozones in the UK
SANTONIAN M.testudunarius
U.socialis
M.coranguinum (pars) Upper H.rostrata Zone
(Northern England only)

Lithostratigraphical marker-beds for the base of the stage[edit]

Southern England: Michael Dean Flint

Northern England: ? between Middleton Top Marl and the High Stacks Flint (Burnett & Whitham, 1999)

East Anglia: ? an un-named flint at 366.5 m depth in the BGS Trunch Borehole [TG 2933 3455] in north Norfolk (Wood et al., 1994); boundary poorly defined in remainder of East Anglia

N. Ireland: basal part of stage not represented by Chalk Group strata

References[edit]

BURNETT, J A & WHITHAM, F. Correlation between the nannofossil and macrofossil biostratigraphies and the lithostratigraphy of the Upper Cretaceous of NE England. Proceedings of the Yorkshire Geological Society, 52, 371-381.

COQUAND, H. 1857. Position des Ostrea columba et biauriculata dans le groupe de la craie inférieure. Bulletin de la Société géologique de France (2), 14, 745-766.

LAMOLDA, M A & HANCOCK, J M. 1996. The Santonian Stage and substages. Bulletin de l'Institut Royal des Sciences Naturelles de Belgique, 66-Supp, 95-102.

WOOD, C J, MORTER, A A & GALLOIS, R W. Appendix 1: Upper Cretaceous stratigraphy of the Trunch Borehole. In ARTHURTON, R S, BOOTH, S J, MORIGI, A N, ABBOTT, M A W & WOOD, C J. 1994. Geology of the country around Great Yarmouth. Memoir of the British Geological Survey.