The BGS Lexicon of Named Rock Units — Result Details

Marsh Farm Formation

Computer Code: MARF Preferred Map Code: MrF
Status Code: Full
Age range: Lutetian Age (GL) — Lutetian Age (GL)
Lithological Description: Laminated clay; wavy to lenticular-bedded sand interbedded with clay in equal proportions; and fine- to medium-grained sparsely glauconitic sand with laminae and intercalations of clay.
Definition of Lower Boundary: Rests on Earnley Sand Formation. Boundary marked by the sharp upward change from glauconitic sands of the Earnley Sand Formation to the thinly bedded clays and silts with glauconitic sand laminae of the Marsh Farm Formation.
Definition of Upper Boundary: Overlain by Selsey Sand Formation whose base is sharply marked by glauconitic sandy silts with a few flints on a burrowed surface.
Thickness: 12-13.5m
Geographical Limits: Eastern Hampshire Basin.
Parent Unit: Bracklesham Group (BRB)
Previous Name(s): Earnley "Division" (-2309)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Seacliffs at Whitecliff Bay, Isle of Wight. 
Reference Section  Bracklesham Bay foreshore 
Reference(s):
Edwards, R A and Freshney, E C. 1987. Lithostratigraphical classification of the Hampshire Basin Palaeogene Deposits (Reading Formation to Headon Formation) Tertiary Research, Vol.8, 43-73. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E314 E315 E331