Grey Downtonian Explained

Period:	Lower Devonian
Age:	Mid-Downtonian (Lowermost Devonian)^[1]

The Grey Downtonian facies occurs in the Downton Castle Sandstone Group^[2] of the British Old Red Sandstone, and more or less straddles the Devonian-Silurian boundary.^[3] The Ludlow Bone Bed and Temeside Shales are sometimes also included in the Grey Downtonian, which is also referred to as the Temeside group, part of the Downton Series.^[4] It is intermediate between the marine flagstones beneath it and the terrestrial deposits above it.^[5] The beds were deposited in a marine environment, with some material being washed in from the nearby land.

Notes and References

1. Allen . J. R. L. . Tarlo . L. B. . 10.1017/S0016756800055345 . The Downtonian and Dittonian Facies of the Welsh Borderland . Geological Magazine . 100 . 2 . 129–155. 1963. 1963GeoM..100..129A .
2. Ørvig . T. O. R. . The Vertebrate Fauna of the Primaeva Beds of the Frænkelryggen Formation of Vestspitsbergen and Its Biostrati-Graphic Significance . Lethaia . 2 . 219–239 . 1969 . 3 . 10.1111/j.1502-3931.1969.tb01849.x . 1969Letha...2..219O .
3. 20494854 . Shelford . P. H. . The Structure and Relationship of the Namurian Outcrop between Duntryleague, Co. Limerick and Dromlin, Co. Tipperary . Proceedings of the Royal Irish Academy . 62 . 255–266 . 1961 .
4. Phipps . C. B. . Reeve . F. A. E. . Stratigraphy and geological history of the Malvern, Abberley and Ledbury Hills . Geological Journal . 5 . 339–368 . 2007 . 2 . 10.1002/gj.3350050209 .
5. 10.1098/rstb.1937.0004 . 92244 . Lang . W. H. . On the Plant-Remains from the Downtonian of England and Wales . Philosophical Transactions of the Royal Society B: Biological Sciences . 227 . 544 . 245–291 . 1937 . 1937RSPTB.227..245L . free .