Blackbrook Group
From Wikipedia, the free encyclopedia
- Blackbrook Reservoir Formation
- Ives Head Formation
- South Quarry Slump Breccia Member
- Lubcloud Greywackes Member
- Morley Lane Tuffs Member
| Blackbrook Group | |
|---|---|
| Stratigraphic range: Ediacaran | |
| Type | Group |
| Unit of | Charnian Supergroup |
| Sub-units | [2]
|
| Underlies | Maplewell Group[2] |
| Thickness | 1,430+ m (4,691+ ft)[2] |
| Lithology | |
| Primary | Tuff |
| Other | Pelite, Greywacke, Breccia, Sandstone, Dacite |
| Location | |
| Region | Leicestershire |
| Country | United Kingdom |
The Blackbrook Group is a geologic group in Leicestershire, and is the oldest group of the Charnian Supergroup. It preserves fossils dating back to the Ediacaran period. It mainly contains pelite, tuff and greywacke.[2]
It is made up of two formations, and is the basal-most unit of the Charnian Supergroup. Uppermost formation within the group is the Blackbrook Reservoir Formation, tuffeceous pelite, tuffs and coarse-grained tuffs.[2] This is underlain by the basal-most formation of the group and supergroup, the Ives Head Formation, which consists of slump breccia, coarse-grained tuffs and dust tuffs, with fine-grained and tuffeceous greywackes in the middle part of the formation, and nearer to its base are sandstones and dacite lavas.[2]
