| Computer Code: |
ULC |
Preferred Map Code: |
ULi |
| Status Code: |
Full |
| Age range: |
Toarcian Age (JT)
— Toarcian Age (JT) |
| Lithological Description: |
[Obsolete: use WHM] Mainly grey, silty mudstones, fossiliferous, with some siltstones. |
| Definition of Lower Boundary: |
Placed at junction of mudstones with underlying Marlstone Rock Formation. |
| Definition of Upper Boundary: |
Placed at base of overlying Inferior Oolite Group (Worcestershire) and base of Midford Sands (Bristol district) and Cotteswold Sands (Malmesbury district). |
| Thickness: |
c.120m |
| Geographical Limits: |
Gloucestershire, Avon, Worcestershire. |
| Parent Unit: |
none recorded or not applicable
|
| Previous Name(s): |
Clay in Upper Lias [Obsolete Name and Code: Use ULC]
(-3106)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| none recorded or not applicable |
| Reference(s): |
| Cave R. 1977. Geology of the Malmesbury District. Memoir of the Geological Survey of Great Britain, Sheet 251 (England and Wales). |
| Formal definition not published. |
| Donovan, D T and Kellaway, G A 1984. Geology of the Bristol district: Lower Jurassic rocks. Memoir of the British Geological Survey, Bristol Special Sheet (England and Wales). |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E216
E234
|
