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): |
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). |
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. |
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. |
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. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E330
E331
|