| Computer Code: |
MIDA |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Tournaisian Age (CT)
— Tournaisian Age (CT) |
| Lithological Description: |
Bedded and nodular anhydrite interbedded with dark grey mudstone and thin beds of dolostone. A thin grey-green and red sandstone marks the base of the formation, with dark grey dolostone and thin dolomitic mudstone beds dominant in the lower part of the unit. |
| Definition of Lower Boundary: |
Unconformable, with grey-green and red sandstone of the Middleton Dale Anhydrite Formation overlying grey and purple mudstone of Ordovician age. |
| Definition of Upper Boundary: |
Sharply unconformable, and defined as the base of the lowermost thick, dark grey dolostone bed of the Woo Dale limestone Formation, overlying anhydrite of the Middleton Dale Anhydrite Formation. |
| Thickness: |
Measured as 73.6 m thick in the Eyam Borehole. |
| Geographical Limits: |
Proved in the subsurface only, in the northern part of the Peak District [SK27]. |
| Parent Unit: |
Not Applicable (-)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
The Eyam borehole (SK27NW), located within the Furness Quarry, Middleton Dale, about 1.3 km SSW of Eyam, from a depth of 1803.25 to 1729.64 m. Dunham, 1973. |
| Reference(s): |
| Waters, C N, Smith, K, Hopson, P M, Wilson, D, Bridge, D M, Carney, J N, Cooper, A H, Crofts, R G, Ellison, R A, Mathers, S J, Moorlock, B S P, Scrivener, R C, McMillan, A A, Ambrose, K, Barclay, W J, and Barron, A J M. 2007. Stratigraphical Chart of the United Kingdom: Southern Britain. British Geological Survey, 1 poster. |
| Dunham, K C. 1973. A recent deep borehole near Eyam, Derbyshire. Nature Physical Science, Vol. 241, 84-85. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E099
|
