Computer Code: |
LUBR |
Preferred Map Code: |
LuBr |
Status Code: |
Full |
Age range: |
Triassic Period (T)
— Triassic Period (T) |
Lithological Description: |
Breccia, sandy breccia, pebbly sandstone and sandstone, reddish brown, commonly calcareous; calcite-veined in places, and locally well-cemented-clasts in breccias; mainly angular platy slate, shale, sandstone and quartz. Thin unit of conglomerate with rounded boulders of Devonian sandstone. Near base, reddish brown, weakly cemented, silty, fine- to medium-grained sandstone unit, up to 70m. |
Definition of Lower Boundary: |
Unconformable: rests on Hangman Sandstone (Eifelian). |
Definition of Upper Boundary: |
Probably unconformable: overlain with probable angular discordance by Mercia Mudstone Group (Triassic). |
Thickness: |
Up to 650 m. estimated. |
Geographical Limits: |
Porlock Basin, west Somerset. Sheet 278 (Minehead). |
Parent Unit: |
Not Applicable (-)
|
Previous Name(s): |
Luccombe Breccia Series [Obsolete Name and Code: Use LUBR]
(-1671)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Area |
Village of Luccombe (SS 911 445), west Somerset. No suitable type section. Small quarries between Luccombe and Tivington. |
Type Area |
Village of Luccombe. |
Type Area |
Village of Luccombe. |
Type Area |
Village of Luccombe. |
Type Area |
Village of Luccombe. |
Reference Section |
Basal sandstone in stream section. |
Reference Section |
Conglomerate in lane section in Huish Ball Steep. |
Reference(s): |
Thomas, A N. 1940. The Triassic Rocks of North-west Somerset. Proceedings of the Geologists' Association, Vol.51, 1-43. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |