The Great Oolite Group is a Middle Jurassic stratigraphic unit that outcrops in southern England. It consists of a complex set of marine deposits primarily mudstone and bioclastic ooidal and fine grained limestone, deposited in nearshore to shelf settings. It is exposed at the surface as a variably thick belt extending roughly NE-SW from the coast of Dorset up to the Humber. It is also present at depth in the Weald and Wessex Basins, as well as offshore. Several of the constituent formations, notably the Taynton Limestone Formation and the Forest Marble Formation are notable for their fossil content, including those of dinosaurs and pterosaurs and some of the earliest mammals.

Paleofauna