The BGS Lexicon of Named Rock Units — Result Details

Bembridge Marls Member

Computer Code: BMBG Preferred Map Code: BM
Status Code: Full
Age range: Priabonian Age (GI) — Priabonian Age (GI)
Lithological Description: Clays and silts with occasional thin sands, lime-mudstones and limestones, contains a low diversity brackish and freshwater molluscan fauna often concentrated in seams.
Definition of Lower Boundary: Erosional interburrowed omission surface on underlying Bembridge Limestone Formation overlain by a 3m thick bed of sand packed with oysters of the Bembridge Marls Member.
Definition of Upper Boundary: Overlain by Hamstead Member of the Bouldnor Formation at an omission surface generally represented by a palaeosol, boundary is marked by a carbonaceous mud locally known as the 'Black Band' above the omission surface.
Thickness: 22 to 34m.
Geographical Limits: Isle of Wight.
Parent Unit: Bouldnor Formation (BOUL)
Previous Name(s): Bembridge Marls (-5235)
Alternative Name(s): Gurnard Member
Stratotypes:
Reference Section  Cliffs and foreshore at Hamstead, Isle of Wight. A complete succession of 21.5m of varicoloured silts and clays with shell beds can be seen at low tides. King (in press); Insole et al. (1998). 
Partial Type Section  Cliff section at Whitecliff Bay, Isle of Wight. Section shows up to 34m of varicoloured silt and clay with shell seams. The upper boundary is not visible here. White (1921). 
Reference Section  Gurnard Ledge, near Cowes (Isle of Wight) where up to 21.5m of varicoloured silts and clays with shell beds are seen. King (in press); Insole et al. (1998). 
Reference(s):
White, H J O. 1921. A short account of the geology of the Isle of Wight. Memoir of the Geological Survey of Great Britain, (1994 reprint). 
Insole, A, Daley, B, and Gale, A. 1998. The Isle of Wight. Geologists’ Association Guide. No. 60. (The Geologists’ Association.)  
King, C. In press. A correlation of Tertiary rocks in the British Isle and adjacent areas. Special Report of the Geological Society of London, No.12. 
Melville, R V and Freshney, E C. 1982. British Regional Geology: the Hampshire Basin and adjoining areas (4th Edition).(London ,HMSO for Institute of Geological Sciences). 
Curry, D, Adams, C G Boulter, M C, Dilley, F C, Eames, F E, Funnell, B M and Wells, M K. 1978. A Correlation of Tertiary rocks in the British Isles. Geological Society of London Special Publication , Vol.12, 1-72. 
Daley, B. 1999. Palaeogene sections of the Isle of Wight. A revision of their description and significance in the light of research undertaken over recent decades. Tertiary Research, Vol.19, 1-69. 
Armenteros, I, Daley, B, and García, E. 1997. Lacustrine and palustrine facies in the Bembridge Limestone (late Eocene, Hampshire Basin) of the Isle of Wight, southern England. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 128, 111-132. 
Curry, D. 1958. The Tertiary. 12-15 in Geologists Association Guides No 25: The Isle of Wight. (Colchester: Benham.)  
Daley, B, and Balson, P. 1999. British Tertiary Stratigraphy. Geological Conservation Review Series Volume 15 Peterborough. (Joint Nature Conservation Committee) 
Forbes, E. 1853. On the fluvio-marine Tertiaries of the Isle of Wight. Quarterly Journal of the Geological Society of London, Vol. 9, 259-270. 
Gale, A S, Huggett, J M, Pälike, H, Laurie, E, Hailwood, E A, and Hardenbol, J. 2006. Correlation of Eocene-Oligocene marine and continental records: orbital cyclicity, magnetostratigraphy and sequence stratigraphy of the Solent Group, Isle of Wight, UK. Journal of the Geological Society of London, Vol. 163, 401-415. 
Insole, A and Daley, B. 1985. A revision of the lithostratigraphy of the Late Eocene and Early Oligocene strata of the Hampshire Basin, Southern England. Tertiary Research, Vol.7, 67-100. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E330 E331