The age, fauna and palaeoenvironment of the Late Triassic fissure deposits of Tytherington, South Gloucestershire, UK

摘要: Important vertebrate faunas occur in fissure deposits of Late Triassic–Jurassic age SW Britain. Although the are well described, their and palaeoenvironment remain poorly understood. One such system was documented detail during quarrying operations at Tytherington has yielded situ palynomorphs that add much information concerning its palaeoenvironment. Significantly, fauna is sauropsid type generally been dated as Norian or pre-Penarth Group transgression also regarded representing a distinct upland fauna. The palynomorphs, which include significant marine component, demonstrate Triassic fissures infilled with (Rhaetian) sediments match specific levels Westbury Formation. In addition, many solutional probably formed Rhaetian consistent fluctuating saline to freshwater environment. There no prima facie evidence formation infilling reptile-bearing before trangression. reptile fauna, includes early dinosaur Thecodontosaurus, inhabited small fire-swept limestone island sea. features herpetofauna entirely this model Quaternary analogues.