The Late Devonian envelops one of Earth's big five mass extinction events at the Frasnian-Famennian boundary, corresponding to the lower and upper Kellwasser black shales. The data of Magnetic susceptibility, Carbon isotopes and LogTi are used to build a cyclostratigraphic time scale. Logarithmic Titanium values were measured using a Bruker M4 Tornado (Vrije Universiteit, Brussels, Belgium), used for the μXRF measurements and operated under near-vacuum conditions (20 mbar). The conditions used were: a 30 W Rh anode metal-ceramic X-ray tube and a 30 mm2 SSD with a resolution of 145 eV (Mn–Ka). The X-ray beam was focused by a poly-capillary lens on a spot with a diameter of 25 mm (Mo–Ka). An integration time of 60 s per point was chosen, satisfying the conditions for reaching the Time of Stable Accuracy and Time of Stable Reproducibility and providing the ideal compromise between high analytical accuracy and precision and high sample throughput.The carbon (δ13C) stable isotope ratios of bulk powered carbonate material were also determined at the Vrije Universiteit Brussel, using a NuPerspective isotope ratio mass spectrometer (IRMS) interfaced with a NuCarb automated carbonate device. Acidification of the samples took place at a temperature of 70 °C. All values are expressed relative to the Vienna Pee Dee Belemnite (‰VPDB) standard. Calibration was carried out using an in-house Marbella limestone (MAR) standard (+ 3.41 ‰VPDB) calibrated against the international NBS-19 standard30. On the basis of replicated measurements of the MAR standard, reproducibility errors on δ13C are < 0.05 ‰ (1 σ).Magnetic susceptibility was measured 3 times on each sample, witha KLY-3 AGICO Kappabridge device from Liege University (Belgium), averaged and weighted to produce mass-specific (m3/kg) data.