| Computer Code: |
MKN |
Preferred Map Code: |
Mkn |
| Status Code: |
Full |
| Age range: |
Permian Period (P)
— Permian Period (P) |
| Lithological Description: |
Clayey fine-grained sandstone (locally medium- or coarse-grained); sandstone, sandy mudstone, silty mudstone, thin breccia beds. The formation passes laterally and downwards into the Heavitree Breccia. |
| Definition of Lower Boundary: |
Overlies thin sequence of Heavitree Breccia in Hill Barton [SX 956 928], Exeter, with fairly sharp upward passage from breccia into a mainly clayey sequence. Around [SX 965 940], the Monkerton Formation rests directly on Whipton Formation. |
| Definition of Upper Boundary: |
Overlain by Dawlish Sandstone: the passage from clayey silty sandstones of the Monkerton Formation takes place within about 1m of strata. |
| Thickness: |
To 40m |
| Geographical Limits: |
Small area northeast of Exeter, Devon, from Hill Barton [SX 956 928] in the west, through Monkerton [SX 965 938], to just beyond the M5 Motorway in the east [SX 974 939]. |
| Parent Unit: |
Exeter Group (EXE)
|
| Previous Name(s): |
Monkerton Member [Obsolete Name and Code: Use MKN]
(-4797)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Monkerton area of Exeter, Devon. Few exposures; outcrop mainly determined by augering. No suitable type section. Small exposures (eg SX 9538 9355, SX 9540 9353) in Hospital Lane reveal sandstone, clayey sandstone and clayey breccia. |
| Reference(s): |
| Bristow, C R, and Scrivener, R C. 1984. The stratigraphy and structure of the Lower New Red Sandstone of the Exeter district. Proceedings of the Ussher Society, Vol. 6, 68-74. |
| Bristow, C R, and Williams, B J. 1984. Geological Notes and Local Details for 1:10,000 Sheets. Sheet SX99SE (Pinhoe and Clyst St Mary, Devon). (Exeter: British Geological Survey.) |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
