A new rodent chronology for the late Neogene of Spain

Abstract

The number of late Neogene Spanish micromammal-containing continental sections with a correlation to the Geomagnetic Time Scale is steadily growing. Nonetheless, well-calibrated sections with dense micromammal records are still rare, biostratigraphic correlations between basins are not straightforward, and ages of uncalibrated sites are poorly constrained. Here, we aim at improving the chronology of Iberian micromammal sections and sites for the interval 8.5–2 Ma by: (i) analyzing qualitative and quantitative similarities between rodent assemblages and turnover in the different basins, (ii) formulating a system of fifteen Iberian assemblage biozones, and (iii) constraining the ages of zone boundaries, assuming isochroneity across basins. Age uncertainty ranges for most known Iberian micromammal sites are obtained by combining regional biozone boundary ages with local magnetostratigraphic records, sedimentation rates and/or evolutionary rates. In addition, our results include new, integrated stratigraphic records from the Jumilla-La Celia and Teruel Basins, which are used to constrain the thus far poorly dated interval covering the latest Tortonian and earliest Messinian (8–7 Ma).