Description: Astronomical tuning of sedimentary records to precise orbital solutions has led to unprecedented resolution in the geological time scale. However, the construction of a consistent astronomical time scale for the Paleocene is controversial due to uncertainties in the recognition of the exact number of 405-kyr eccentricity cycles and accurate correlation between key records. Here, we present a new Danian integrated stratigraphic framework using the land-based Zumaia and Sopelana hemipelagic sections from the Basque Basin and deep-sea records drilled during Ocean Drilling Program (ODP) Legs 198 (Shatsky Rise, North Pacific) and 208 (Walvis Ridge, South Atlantic) that solves previous discrepancies. The new coherent stratigraphy utilises composite images from ODP cores, a new whole-rock d13C isotope record at Zumaia and new magnetostratigraphic data from Sopelana. We consistently observe 11 405-kyr eccentricity cycles in all studied Danian successions. We achieve a robust correlation of bioevents and stable isotope events between all studied sections at the ~100-kyr short-eccentricity level, a prerequisite for paleoclimatic interpretations. Comparison with and subsequent tuning of the records to the latest orbital solution La2011 provides astronomically calibrated ages of 66.022 ± 0.040 Ma and 61.607 ± 0.040 Ma for the Cretaceous-Paleogene (K-Pg) and Danian-Selandian 105 (D-S) boundaries respectively. Low sedimentation rates appear common in all records in the mid-Danian interval, including conspicuous condensed intervals in the oceanic records that in the past have hampered the proper identification of cycles. The comprehensive interbasinal approach applied here reveals pitfalls in time scale construction, filtering techniques in particular, and indicates that some caution and scrutiny has to be applied when building orbital chronologies. Finally, the Zumaia section, already hosting the Selandian Global Boundary Stratotype Section and Point (GSSP), could serve as the global Danian unit stratotype in the future.

Description: Here we present calcareus nannofossil and colour datasets from the hemipelagic lower Ypresian Arnakatxa section (Basque-Cantabrian basin, western Pyrenees). The Arnakatxa coastal cliffs, which constitute the present study area, are located approximately 15 km northwest of Bilbao (43°23'34.4N, 2°59'24.2W, altitude 0 m). The expanded hemiplegic succession offered a potentially valuable orbitally paced geological record. Sampling was carried out in 2015. For the study of calcareous nannofossils 65 hand samples were collected (average spacing of about 50 cm). For colour analysis, 635 rock-powder samples were collected (average resolution of ~5 cm) using a standard cordless drill with an 8 mm bit. Slides for nannofloral analysis were prepared according to Flores and Sierro (1997), avoiding any mechanical or physical disturbance of the samples that could modify the original fossil assemblages. A Zeiss Axioplan2 petrographic microscope at 1250× magnification was used to analyze the samples. Quantitative analysis was performed by counting at least 300 specimens per sample. Additionally, three random traverses (~9 mm2) were analyzed on each slide in order to detect rare but biostratigraphically significant species. The rock powder samples were stored in transparent antiglare prismatic plastic vials (3 ml) and scanned at high-resolution (600 dpi) using a desktop office scanner in a dark room. The average colour value of a homogeneous rectangular area covering 10-20% of the scanned image of each vial was measured using ImageJ software version 1.50i. Average colour value represents to the mean pixel RGB value of the selected area, which is equivalent to the brightness value. In order to perform a cyclostratigraphic analysis, the colour data series was linearly interpolated and the LOESS regression trend subtracted. The Astrochron code commands used to perform that spectral analysis are herein available.

Description: Here we present calcareus nannofossil and colour datasets from the hemipelagic lower Ypresian Arnakatxa section (Basque-Cantabrian basin, western Pyrenees). The Arnakatxa coastal cliffs, which constitute the present study area, are located approximately 15 km northwest of Bilbao (43°23'34.4N, 2°59'24.2W, altitude 0 m). The expanded hemiplegic succession offered a potentially valuable orbitally paced geological record. Sampling was carried out in 2015. For the study of calcareous nannofossils 65 hand samples were collected (average spacing of about 50 cm). For colour analysis, 635 rock-powder samples were collected (average resolution of ~5 cm) using a standard cordless drill with an 8 mm bit. Slides for nannofloral analysis were prepared according to Flores and Sierro (1997), avoiding any mechanical or physical disturbance of the samples that could modify the original fossil assemblages. A Zeiss Axioplan2 petrographic microscope at 1250× magnification was used to analyze the samples. Quantitative analysis was performed by counting at least 300 specimens per sample. Additionally, three random traverses (~9 mm2) were analyzed on each slide in order to detect rare but biostratigraphically significant species. The rock powder samples were stored in transparent antiglare prismatic plastic vials (3 ml) and scanned at high-resolution (600 dpi) using a desktop office scanner in a dark room. The average colour value of a homogeneous rectangular area covering 10-20% of the scanned image of each vial was measured using ImageJ software version 1.50i. Average colour value represents to the mean pixel RGB value of the selected area, which is equivalent to the brightness value. In order to perform a cyclostratigraphic analysis, the colour data series was linearly interpolated and the LOESS regression trend subtracted. The Astrochron code commands used to perform that spectral analysis are herein available.