| Computer Code: |
TNM |
Preferred Map Code: |
TNM |
| Status Code: |
Index Level |
| Age range: |
Caradoc Series (O4)
— Caradoc Series (O4) |
| Lithological Description: |
[Obsolete: use LIT, GWD, GY] Dacitic ignimbrites and lava contains three defined beds - in ascending order these are the Little Stand Tuff, Great Whinscale Dacite and the Grey Friar Tuff; in places bedded tuffs and other laterally impersistent andesitic ignimbrites separate these named beds. |
| Definition of Lower Boundary: |
Defined at base of thin-bedded tuffs underlying the nodular rhyolitic ignimbrite (Little Stand Tuff). |
| Definition of Upper Boundary: |
Top defined by overlying bedded tuffs on porphyritic andesite sheets. |
| Thickness: |
200 metres in type section; lateral variations 85-200m; absent north of Hard Knott-Stonesty Gill. |
| Geographical Limits: |
Not defined. |
| Parent Unit: |
none recorded or not applicable
|
| Previous Name(s): |
Great Whinscale Member [Obsolete Name And Code: See TNM]
(GWM)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Tongue House, High Close, Sheet 38 (Ambleside). |
| Reference(s): |
| Millward, D, Johnson, E W, Mathieson, N A, Branney, M, Beddoe-Stephens, B, and Allen, P M. Not yet published. A revision of the lithostratigraphy of the Borrowdale Volcanic Group in the south-western part of the English Lake District, and on 1:10,000 maps SD19NE and 19NW. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E038
|
