Palaeoecology and event stratigraphy of the Wealden - Lower Greensand transition on the Isle of Wight

Event stratigraphy combines sedimentological, trace fossil and palaeoecological criteria, in identifying six fades associations in the Vectis Formation (Weald Shales) of the Isle of Wight. This sequence suggests that prior to deposition of the marine Lower Greensand (Aptian-Albian), the Vectis Formation underwent a gradual increase in marine influence. Storm/flood event beds are common, and black shales with a lack of benthos are ascribed to limited oxygenation in the Vectis Formation lagoon. As far as eustatic models are concerned it is suggested that the Upper Barremian to Aptian sea-level rise was gradual, the Perna Beds (lowest Aptian) forming at the restricted to normal marine transition during a period of base-level rise.