UPPERMOST WEALDEN FACIES AND LOWER GREENSAND GROUP (LOWER-CRETACEOUS) IN DORSET, SOUTHERN ENGLAND - CORRELATION AND PALEOENVIRONMENT

New sections in the historically and palaeogeographically important Lower Greensand Group of Swanage are described, and related to those in previous accounts. At the time of deposition during the Aptian and early Albian, the Swanage area lay between open-marine conditions of the Channel Basin to the east and nonmarine/estuarine conditions to the west. The discovery of ammonites at two previously undated horizons along with known ammonite occurrences, and the sampling of associated sediments for palynological investigation have allowed new integrated litho- and biostratigraphic analyses to be carried out. Precise correlation with the Aptian-Albian type section of Chale Bay on the Isle of Wight is constrained through documentation of an intermediate area, Compton Bay, in the west of the island. Depositional changes may be related to the known event stratigraphy of the Aptian-Albian of southern England. Facies and thickness changes in the Lower Greensand Group of the Dorset coast are documented, allowing correlation of these marginal marine sections.