| Computer Code: |
PERG |
Preferred Map Code: |
PERG |
| Status Code: |
Full |
| Age range: |
Caradoc Series (O4)
— Caradoc Series (O4) |
| Lithological Description: |
Diverse porphyritic autobrecciated lavas, volcanic tuffs, breccias and agglomerates; hawaiite/mugearite in composition. |
| Definition of Lower Boundary: |
Presumed conformable base on Cat Cleugh Formation. |
| Definition of Upper Boundary: |
Faulted locally; otherwise top of the Bail Hill Volcanic Group, overlain conformably by Kirkcolm Formation. |
| Thickness: |
c.1000m |
| Geographical Limits: |
Bail Hill area, 4km north west of Sanquhar, Dumfries, Scotland. |
| Parent Unit: |
Bail Hill Volcanic Group (BAIL)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Exposures around Bail Hill and along Grain Burn. |
| Reference(s): |
| McMurtry, M J, 1980. The Ordovician rocks of the Bail Hill area, Sanquhar, south Scotland. Volcanism and sedimentation in the Iapetus Ocean. Unpublished PhD thesis (University of St. Andrews). |
| Floyd, J D, 1996. Lithostratigraphy of the Ordovician rocks in the Southern Uplands: Crawford Group, Moffat Shale Group, Leadhills Supergroup. Transactions of the Royal Society of Edinburgh: Earth Sciences, Vol.86, 153-165. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
S015
|
