This file includes new data on the carbon-isotope composition of bulk organic matter (δ¹³Corg) from the core 4530-A (Horní Beřkovice), western part of the Bohemian Cretaceous Basin. The interval covers the uppermost Cenomanian through Middle Turonian. Samples were analyzed in the Institute of Geochemistry, Mineralogy and Mineral Resources, Charles University, Prague. Stable isotopic composition of carbon was determined using a Thermo Flash 2000 elemental analyzer connected to a Thermo Delta V Advantage isotope ratio mass spectrometer in a Continuous Flow IV system. Minimal weight of samples depends on the wt.% amount of carbon element. Samples wrapped in tin capsules were combusted. Released gases (CO2) separated in a GC column was transferred to MS source through a capillary. Isotope ratios are reported as delta (δ) values and expressed relative to VPDB. Delta values are normalized to a calibration curve based on international standards IAEA-CH-6, IAEA-CH-3 and IAEA 600.

Thermo Flash 2000 elemental analyzer connected to a Thermo Delta V Advantage isotope ratio mass spectrometer in a Continuous Flow IV system. Minimal weight of samples depends on the wt.% amount of carbon element. Samples wrapped in tin capsules were combusted. Released gases (CO~2~) separated in a GC column was transferred to MS source through a capillary. International standards IAEA-CH-6, IAEA-CH-3 and IAEA 600.