Grey Downtonian

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Grey Downtonian
Stratigraphic range: 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.[1]

  1. ^ a b Allen, J. R. L.; Tarlo, L. B. (1963). "The Downtonian and Dittonian Facies of the Welsh Borderland". Geological Magazine. 100 (2): 129 –155. doi:10.1017/S0016756800055345. 
  2. ^ Ørvig, T. O. R. (1969). "The Vertebrate Fauna of the Primaeva Beds of the Frænkelryggen Formation of Vestspitsbergen and Its Biostrati-Graphic Significance". Lethaia. 2: 219. doi:10.1111/j.1502-3931.1969.tb01849.x. 
  3. ^ Shelford, P. H. (1961). "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. JSTOR 20494854. doi:10.2307/20494854. 
  4. ^ Phipps, C. B.; Reeve, F. A. E. (2007). "Stratigraphy and geological history of the Malvern, Abberley and Ledbury Hills". Geological Journal. 5: 339. doi:10.1002/gj.3350050209. 
  5. ^ Lang, W. H. (1937). "On the Plant-Remains from the Downtonian of England and Wales". Philosophical Transactions of the Royal Society B: Biological Sciences. 227 (544): 245–291. Bibcode:1937RSPTB.227..245L. JSTOR 92244. doi:10.1098/rstb.1937.0004.