The BGS Lexicon of Named Rock Units — Result Details

Seeley Formation

Computer Code: SEEL Preferred Map Code: notEntered
Status Code: Full, pending ratification
Age range: Oxfordian Age (JO) — Oxfordian Age (JO)
Lithological Description: Carbonate-cemented, fine-grained siltstone and sandstone (in two main, variably developed, upwardly coarsening siltstone-sandstone cycles). Laterally becomes more calcareous eastwards and passes into oolitic limestones of the Corallian Formation (Offshore).
Definition of Lower Boundary: The lower boundary is marked by a downward change from mudstone (Seeley Formation) to sandstone (Leckenby Formation), which is reflected in the downward decrease in gamma values and increase in velocity.
Definition of Upper Boundary: The upper boundary is marked by the downward change from grey, calcareous silty mudstones (Woodward Formation) into calcareous sandstone and siltstone (Seeley Formation) and an abrupt decrease in gamma values and increase in velocity.
Thickness: Up to 70 m on the East Midlands Shelf.
Geographical Limits: East Midlands Shelf, North Sea UK Quadrants 47, 48, 51 and 52.
Parent Unit: Humber Group (HMBG)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  North Sea well 47/14a-2 at 966-1033 m depth. Lott and Knox (1994). 
Reference Section  North Sea well 48/22-3 at 720.5-763 m depth. Lott and Knox (1994). 
Type Section  North Sea well 47/15a-3 at 1066-1134.5 m depth. Lott and Knox (1994). 
Reference Section  North Sea well 47/9a-7 at 940.5-1012 m depth. Lott and Knox (1994). 
Reference(s):
Lott, G K and Knox, R W O'B. 1994. 7. Post-Triassic of the Southern North Sea. In: Knox, R W O'B and Cordey, W G (eds.) Lithostratigraphic nomenclature of the UK North Sea. [British Geological Survey, Nottingham]. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable