The BGS Lexicon of Named Rock Units — Result Details

Shenley Limestone Member

Computer Code: SHEN Preferred Map Code: notEntered
Status Code: Full
Age range: Albian Age (KA) — Albian Age (KA)
Lithological Description: Lenticular beds of a pale brown, phosphatic limestone with scattered polished goethite ooliths (Owen 1972; Smart, 1997). It may be slightly limonitic and glauconitic. Brachiopods common.
Definition of Lower Boundary: The base is taken where a thin, gritty ironstone ("carstone") overlying silty beds at the top of the Woburn Sands Formation passes up into a sandy mudstone associated with lenticular beds of a pale brown phosphatic limestone with scattered polished goethite ooliths (Shenley Limestone Member) (Owen, 1972; Smart, 1997).
Definition of Upper Boundary: The top is taken where phosphatic limestone of the Shenley Limestone Member is overlain by a 1.2m-thick fissile, red mudstone informally called "Red Clay" or the "Cirripede Bed" of the Gault Formation.
Thickness: Up to c. 0.1m.
Geographical Limits: Restricted to the area around Leighton Buzzard. Leighton Buzzard Sheet 1:50k sheet number 220.
Parent Unit: Munday's Hill Phosphatic Sandstone Formation (MHPS)
Previous Name(s): Shenley Limestone Bed (-521)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  Bryants Lane Quarry, north of Leighton Buzzard. Shephard Thorne et al., 1994. 
Type Area  Shenley Hill [SP 93 27] near Leighton Buzzard. 
Reference Section  Munday's Hill, 420m northwest of Mile Tree Farm, Heath and Reach. Owen, 1972. 
Reference(s):
Lamplugh, G W and Walker, J F. 1903. On a fossiliferous band at the top of the Lower Greensand near Leighton Buzzard (Bedfordshire). Quarterly Journal of the Geological Society, London, Vol.59, 234-265. 
Lamplugh, G W. 1922. On the junction of the Gault and Lower Greensand near Leighton Buzzard, Bedfordshire. Quarterly Journal of the Geological Society of London, Vol.78, 1-81. 
Owen, H G. 1972. The Gault and its junction with the Woburn Sands in the Leighton Buzzard area, Bedfordshire and Buckinghamshire. Proceedings of the Geologists' Association, Vol.83, 287-312. 
Eyers, J. 1995. Correlation of the Lower Greensand Group (Woburn Sands and Carstone) of the Bedfordshire Province, England. Cretaceous Research, Vol.16, 385-413. 
Smart, P J. 1997. The basal Gault and Gault-Woburn Sands junction beds in Chamberlain's Barn Quarry, Leighton Buzzard, Bedfordshire, England. Proceedings of the Geologists' Association, Vol.108, 287-292. 
Shepard-Thorn, E R, Moorlock, B S P, Cox, B M, Allsop, J M and Wood, C J. 1994. Geology of the country around Leighton Buzzard. Memoir of the British Geological Survey, Sheet 220 (England and Wales). 
Eyers, J. 1991. The influence of tectonics on early Cretaceous sedimentation in Bedfordshire, England. Journal of the Geological Society of London, Vol. 149, 405-414. 
Casey, R, 1961. The stratigraphical palaeontology of the Lower Greensand. Palaeontology, Vol.3, 487-621. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable