Computer Code: |
HM |
Preferred Map Code: |
notEntered |
Status Code: |
Full |
Age range: |
Priabonian Age (GI)
— Rupelian Age (GR) |
Lithological Description: |
Predominantly red, green and grey clays, silts and sands with a fauna of freshwater molluscs, silty clays are locally laminated and carbonaceous. Includes thin blue and black clays with a marine influence. |
Definition of Lower Boundary: |
Marked by the base of a 0.5m thick carbonaceous black clay with rootlets, locally known as the 'Black Band'. The basal contact is an omission surface, overlying a paleosol at the top of the Bembridge Marls Member (Hooker et al., 2004). |
Definition of Upper Boundary: |
Top is a sharp but apparently conformable (King, in press) contact beneath the shelly brown clays of the Cranmore Member. |
Thickness: |
Between 58m and 69m on the eastern and western sides of the Isle of Wight respectively. King (in press) gives a total of 78m for this member in the cliffs and on the foreshore between Bouldnor and Hamstead Ledge, Isle of Wight. |
Geographical Limits: |
Isle of Wight, Hampshire, England. |
Parent Unit: |
Bouldnor Formation (BOUL)
|
Previous Name(s): |
Lower Hamstead Beds
(-5236)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Section |
Cliff section and foreshore between Hamstead and Bouldnor. White (1921). |
Reference(s): |
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. |
Hooker, J J, Collinson, M E, and Sille, N P. 2004. Eocene-Oligocene mammalian faunal turnover in the Hampshire Basin, UK: calibration to the global time scale and the major cooling event. Journal of the Geological Society, London, Vol. 161, 161-172. |
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). |
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. |
Reid, C, and Strahan, A. 1889. Geology of the Isle of Wight. Mem. Geol. Surv. G.B., (2nd edition). (Geological Survey of England and Wales.) |
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). |
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. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E330
E331
|