| Coalbrookdale Formation | |
|---|---|
| Stratigraphic range: Homerian | |
 An arthropod (reconstruction) named Offacolus kingi, the most abundant fossil of Coalbrookdale formation | |
| Type | Geological formation |
| Underlies | Buildwas Formation |
| Overlies | Much Wenlock Limestone Formation |
| Area | 10,000 km2 (3,900 sq mi) |
| Thickness | 192–265 m (630–869 ft) |
| Lithology | |
| Primary | Mudstone |
| Other | Limestone |
| Location | |
| Location | England–Wales border |
| Coordinates | 52°25′N 3°00′W / 52.417°N 3.000°W |
| Region | Powys and Herefordshire |
| Country | United Kingdom |
| Extent | 5.2 miles (8.4 km) |
| Type section | |
| Named for | Coalbrookdale |
| Coordinates | 52°25′N 3°00′W / 52.417°N 3.000°W |
| Approximate paleocoordinates | 52°25′N 3°00′W / 52.417°N 3.000°W |
Coalbrookdale Formation,[1] earlier known as Wenlock Shale or Wenlock Shale Formation[2][3] and also referred to as Herefordshire Lagerstätte in palaeontology,[4] is a fossil-rich deposit (Konservat-Lagerstätte) in Powys and Herefordshire at the England–Wales border in UK. It belongs to the Wenlock Series of the Silurian Period within the Homerian Age (about 430 million years ago). It is known for its well-preserved fossils of various invertebrate animals many of which are in their three-dimensional structures. Some of the fossils are regarded as earliest evidences and evolutionary origin of some of the major groups of modern animals.[5]
Roderick Murchison first described the geological setting of Coalbrookdale Formation by which he gave the name Silurian in 1935, referring to the Silures, a Celtic tribe of Wales. It is assigned to the Wenlock Group in 1978 based on the age of crustacean fossils found around the region. Robert J. King of the University of Leicester discovered the first unique fossil in 1990. The fossil, an arthropod was reported in 1996 and described in 2000 as Offacolus kingi. Since then, over 30 species of arthropods, polychaete worms, sponges, mollusks, echinoderms, and lobopods have been described; with about 30 species in store yet to be identified.
- ^ Cite error: The named reference
:2was invoked but never defined (see the help page). - ^ Davis, James Edward (1850). "On the Age and Position of the Limestone of Nash, near Presteign, South Wales". Quarterly Journal of the Geological Society. 6 (1–2): 432–439. doi:10.1144/GSL.JGS.1850.006.01-02.48. ISSN 0370-291X. S2CID 129638356.
- ^ "Coalbrookdale Formation". British Geological Survey. Archived from the original on 11 January 2022.
- ^ Siveter, David (2008). "The Silurian Herefordshire Konservat-Lagerstätte: a unique window on the evolution of life" (PDF). Proceedings of the Shropshire Geological Society. 13: 83–88.
- ^ Siveter, Derek J.; Briggs, Derek E. G.; Siveter, David J.; Sutton, Mark D. (2020). "The Herefordshire Lagerstätte: fleshing out Silurian marine life". Journal of the Geological Society. 177 (1): 1–13. Bibcode:2020JGSoc.177....1S. doi:10.1144/jgs2019-110. ISSN 0016-7649. S2CID 202180857.