Burton Formation (elevated)
(From NPD Bulletin no. 3)
Dunlin Group
Name
Named by Deegan and Scull (1977) who gave it "sub-unit" status.
Well type section
UK well 211/29-3 (Shell), from 2950.5 m to 2993 m, coord N 61°08'06", E 01°43'36.5", (Fig. 10).
Well reference section
Norwegian wells 33/9-1 (Mobil), from 2801 m to 2838 m, coord N 61°15'O7.5" E01°50'25.8" (Fig. 11).
Thickness
42.5 m in the type well and 37 m in the reference well.
Lithology
In the type well it consists of a uniform development of dark grey to reddish-grey, soft non-calcareous claystone and shale, which may be in part slightly carbonaceous.
Boundaries
The formation is normally represented on both gamma ray and sonic logs by smooth linear almost constant readings, reflecting the lithological uniformity. The upper and lower contacts are identified where this log character changes.
Distribution
Although the log character changes slightly away from the type section, the formation can be recognised over a wide area of the northern North Sea. The formation has not been identified on the Horda Platform. It represents essentially a basinal facies and passes laterally into the Amundsen Formation in marginal areas.
Occurrences of formation tops in wells
Age
Sinemurian - Pliensbachian