Major changes in watermass chemistry during the opening of the central segment of the South Atlantic, and oceanic anoxic events (OAEs 1a to 1d), represent dramatic events that affected the ocean–atmosphere system during the Early Cretaceous. This thesis addresses the chemostratigraphic correlation of Tethyan and South Atlantic sections based on carbon-, sulphur- and strontium-isotopes (δ¹³C, δ³⁴S and ⁸⁷Sr/⁸⁶Sr) integrated with other methods ...