Sur les divisions du Dogger dans la vallee de la Creuse (Indre); correlation avec le sud-est du Bassin parisien
Abstract Stratigraphy of the Dogger (middle Jurassic) in the southwestern part of the Paris basin, at the north border of the Central Massif is very poorly known because facies are monotonous and outcrops and fossils are scarce. A starting point for working out the stratigraphy is provided by the Creuse river valley, from Argenton-sur-Creuse northwestward to St. Gaultier. Stratigraphic correlations with the southeastern part of the Paris basin were made from 21 good outcrops in the Creuse valley area despite the lack of characteristic ammonites. Dogger formations total more than 100 m thickness, chiefly marine neritic limestones, with intercalated marl in the upper portion. Several meters of lagoonal marl and lignite above the base of the Dogger are transitional from lower to middle Bathonian (upper Dogger). Brachiopods and corals, including reef types, are the chief means of correlation.