| Computer Code: |
BLHB |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Thanetian Age (GT)
— Thanetian Age (GT) |
| Lithological Description: |
The Bullhead Bed usually comprises well-rounded flint gravel ranging in size and shape to cobbles and fine boulders of unworn nodular flint, within a dark greenish grey or black glauconitic sandy clay or clayey sand matrix. The flint nodules (the 'bullheads'), which can be up to 0.3 m in diameter, are characteristically green-coated. Fossils derived from the Chalk occur in places. |
| Definition of Lower Boundary: |
none recorded or not applicable
|
| Definition of Upper Boundary: |
none recorded or not applicable
|
| Thickness: |
The Bullhead Bed is generally up to 0.5 m thick, but in parts of North London it is up to 1.5 m thick, with an average of about 1 m (Newman, 2009, p.18). |
| Geographical Limits: |
none recorded or not applicable
|
| Parent Unit: |
Base Bed Member (BSBD)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| none recorded or not applicable |
| Reference(s): |
| Newman, T. 2009. The impact of adverse geological conditions on the design and construction of the Thames Water Ring Main in Greater London, UK. Quarterly Journal of Engineering Geology and Hydrogeology 42, 5-20. |
| Aldiss, D T. 2014. The stratigraphical framework for the Palaeogene successions of the London Basin, UK. British Geological Survey Open Report OR/14/008. 95 pp. |
| Curry, D. 1958. Part 3a XII Palaeogene. Lexique Stratigraphique International. Whittard, W F, and Simpson, S (editors). Vol. 1 Europe (Paris: Centre Nationale de la Research Scientifique.) |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E223
E241
E274
|
