The Gray Sandstone Group is a late Silurian lithostratigraphic group (a sequence of rock strata) in west Wales. The strata are exposed in the coast around the Milford Haven area; outcrops occur either side of Marloes Bay. Besides quartzitic sandstones and mudstones, sandy rottenstones are found at outcrop. Fossils within the rottenstone beds include brachiopods and corals.[1] The rocks of this group have also previously been known as the Gray Sandstone Series.[2]
| Gray Sandstone Group | |
|---|---|
| Stratigraphic range: Wenlockian (Silurian) | |
 Thick sandstone units of the Gray Sandstone Group outcropping on the coast, just west of Marloes Sands | |
| Type | Group |
| Underlies | Red Marls Formation |
| Overlies | Coralliferous Group |
| Thickness | circa 274 - 609m |
| Lithology | |
| Primary | quartzitic sandstones |
| Other | mudstones |
| Location | |
| Country | Wales |
| Extent | south Pembrokeshire |
References
edit- ^ Howells, M.F. 2007 British Regional Geology: Wales (Keyworth, Nottingham. British Geological Survey) pp86, 89-90
- ^ http://www.bgs.ac.uk/Lexicon/lexicon.cfm?pub=GSA (BGS on-line lexicon of rock units)