Microvertebrates from a Rhaetian neptunian dyke at Holwell, Somerset: Dating the fissures

• Published in: Proceedings of the Geologists' Association Vol. 136; no. 4; p. 101112
• Main Authors: Weeks, Oliver J., Cooper, Rebecca B., Whiteside, David I., Duffin, Christopher J., Copp, Charles, Hildebrandt, Claudia, Hutchinson, Deborah, Benton, Michael J.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2025
• Subjects: Bristol; Chondrichthyes; Ichthyosauria; Osteichthyes; Penarth Group; Rhaetian; Rhaetian bone bed; Westbury Formation; Ichthyosauria; Rhaetian bone bed; Bristol; Rhaetian; Westbury Formation; Chondrichthyes; Penarth Group; Osteichthyes

Dating the Mesozoic-aged fissure deposits around Bristol and South Wales has been problematic, with ages of the older examples disputed as either Carnian or Rhaetian, a 30-million-year difference. The deposits filling fissures at Holwell, Somerset offer a chance to establish a date for at least one...