A first high-resolution carbon isotope stratigraphy from the Boreal (NW Germany) for the Berriasian to Coniacian interval—implications for the timing of the Aptian–Albian boundary

High-amplitude changes in sedimentary δ 13 C characterize the Cretaceous system and have been proven useful for supra-regional chemostratigraphic correlation. In Cretaceous, these perturbations indicate large shifts between global carbon reservoirs that are usually caused by volcanic activity of igneous provinces, widespread deposition thick organic carbon-rich sequences and/or orbital parameters. Here, we present an upper Berriasian to lower Coniacian (c. 142–88 Ma) composite isotope record based on 14 drill cores, 2 outcrops, almost 5,000 samples. The total comprises a thickness more than 1,500 m. All cores successions located larger Hanover area, which represents depocenter North German Lower Saxony Basin Early mid-Cretaceous times. Northern Germany, Boreal sediments predominantly represented CaCO 3 -poor mud siltstones up 2,000 m thickness, become carbonate-rich during Albian–Cenomanian transition even chalkier Cenomanian interval. reveals number key events, including Valanginian Weissert Event, Oceanic Anoxic Events (OAEs) 1a d, Kilian Event (Aptian–Albian boundary, part OAE 1b). For early Late Mid-Cenomanian (Cenomanian–Turonian Boundary Event), Navigation among others, identified. Aptian–Albian boundary has identified herein first time Europe. Based evaluation its relative position Vöhrum tuff, tentatively propose slightly older age c. 113.65 Ma instead 113.2 Ma. observed events enable detailed stratigraphic comparison with Tethyan other records associated paleoenvironmental data. Thus, this new chemostratigraphy provides unique opportunity potentially overcome many still existing Boreal–Tethyan correlation issues. presented can be considered complete, albeit 2-Myr gap Albian is likely, condensed intervals occur specifically Aptian.