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The paleobiogeography of hominoids exhibits a puzzling pattern of migrations between and within Africa and Eurasia. A precise dating of hominoid-bearing localities is therefore essential to reveal the timing, direction and possible causes of dispersals. Here, we present a bio-magnetostratigraphic analysis of the section of Engelswies (Southern Germany, Upper Freshwater Molasse, North Alpine Foreland Basin) where the oldest Eurasian hominoid was found. Our paleomagnetic results reveal a very short normal and a reverse magnetic polarity for the entire section. The polarity record is correlated to the Astronomical Tuned Neogene Time Scale using an integrated stratigraphic approach. This approach follows the chronostratigraphic framework for the Upper Freshwater Molasse, which combines magnetostratigraphy with biostratigraphic, lithostratigraphic and 40 Ar/ 39 Ar dating results. According to this outcome, the reverse polarity of the Engelswies section most likely correlates to magnetochron C5Cr. The origin of the short normal polarity remains enigmatic. The magnetostratigraphic calibration and the evolutionary level of the Engelswies small mammal fauna suggest an age of 17.1–17.0 Ma (Early Karpatian, Early Miocene) for the oldest Eurasian hominoid, and roughly confirm the estimates of Heizmann and Begun (2001) . The estimated age suggests that the first hominoids in Eurasia are contemporaneous with Afro-Arabian afropithecins, and dispersal may have been facilitated by intra-Burdigalian (∼18–17 Ma) sea-level low stands and the beginning of the Miocene Climate Optimum. The paleoclimatic and environmental reconstruction of the Engelswies locality indicates a lakeshore environment near dense subtropical rain forest vegetation, where paratropical temperatures (mean annual temperature around 20 °C) and humid conditions (mean annual precipitation > 1.100 mm) prevailed.

A detailed integrated stratigraphic study (biostratigraphy and magnetostratigraphy) was carried out on five sections from the western part of the Bavarian Upper Freshwater Molasse of the North Alpine Foreland Basin (NAFB), greatly improving the chronostratigraphy of these sediments. The sections belong to the lithostratigraphic units Limnische Untere Serie (UL) and Fluviatile Untere Serie (UF) and contain 19 (mostly new) small-mammal bearing levels, significantly refining the local biostratigraphy. Radiometric ages obtained from glass shards from tuff horizons are used together with the biostratigraphic information for constructing and confirming the magnetostratigraphic correlation of the studied sections to the Astronomical Tuned Time Scale (ANTS04; Lourens et al. in Geologic Time Scale 2004, Cambridge University Press, 2004). This correlation implies that the UL lithostratigraphic unit corresponds to the latest Ottnangian and the Early Karpatian, whereas the UF corresponds to the Karpatian and the Early Badenian. This indicates that the Brackish- to Freshwater Molasse transition already occurred during the late Ottnangian. The pre-Riesian hiatus occurred in the latest Karpatian and lower Early Badenian in Eastern Bavaria and Bohemia and in the Late Karpatian and earliest Badenian in Western Bavaria. The geochemical and Ar-Ar data of volcanic ashes suggest that highly evolved silicic magmas from a single volcano or volcanic center, characterized by a uniform Nd isotopic composition, erupted repetitively over the course of at least 1.6 Myr. Three phases of eruptive activity were identified at 16.1 ± 0.2 Ma (Zahling-2), 15.6 ± 0.4 Ma (Krumbad), and 14.5 ± 0.2 Ma (Heilsberg, Hegau). The correlation of the local biostratigraphic zonation to the ANTS04 enables further the characterization of both the Ottnangian-Karpatian and Karpatian-Badenian boundaries in the NAFB by small-mammal biostratigraphy. According to these results the Ottnangian-Karpatian boundary is contemporaneous with the first appearance datum of Megacricetodonbavaricus (in the size of the type population) and the first common occurrence of Keramidomys thaleri, whereas Ligerimys florancei, Melissiodon dominans and Prodeinotherium aff. bavaricum have been already disappeared during the late Ottnangian. The Karpatian-Badenian boundary is characterized by a significant size increase of the large Megacricetodon lineage and possibly a (re-)immigration of Prodeinotherium bavaricum.

Upper Miocene mudflat and marginal lacustrine sediments were deposited on the fringes of an alluvial-fan system in the low-gradient, endorheic southern Teruel Basin, northeast Spain. The 147-m-thick Prado succession consists of 55 meter-scale sedimentary cycles, displaying a clastic-rich and a carbonate-rich interval. The clastic-rich parts are weakly pedogenically modified, red to yellow-orange mudstones and are interpreted as deposits of a well-drained mudflat. The carbonate-rich sediments consist of calcretes, marls, and muddy limestones. The calcretes range from dispersed nodules to massive nodular and are interpreted to be of pedogenic or phreatic origin. The marls and muddy limestones are light- to dark-gray and rich in organic matter, shell fragments, and gastropods. They are interpreted as ephemeral pond to marginal lacustrine deposits. A composite sedimentary cycle model is presented summarizing the different facies and their vertical distribution throughout the Prado area. On a 10 m scale, distinct stratigraphic intervals show lithologic trends representing alternating wetter and drier paleoenvironments. Cycle characteristics are laterally consistent, whereby limestone beds pinch out towards the basin margin and thicken towards the central parts of the 10-km-wide and 20-km-long subbasin. The high-resolution magnetostratigraphy resolves four normal-polarity and four reversed-polarity intervals that are straightforwardly correlated to chron interval C5n.2n to C5Ar.1r in the ATNTS04 time scale. The resulting age control indicates a duration of 19 to 23 kyr for the meter-scale lithofacies cycles, suggesting control by precession-driven climate change. An astronomical tuning is established by correlating each cycle to the La2004 precession curve using recently recalibrated ages for the polarity reversals as a starting point. The resulting astronomical ages for the reversals in the Prado section are consistent with the astronomically calibrated magnetostratigraphy and cyclostratigraphy of the marine Monte dei Corvi section in Italy. At Prado, three intervals with thicker-than-average cycle thickness most likely reflect obliquity influence during 405 kyr eccentricity minima when precession amplitudes are low. This corroborates the orbital forcing hypothesis of the lithofacies cycles and the astronomical tuning of the Prado succession. The combined magnetostratigraphy and cyclostratigraphy method applied in this study shows the high potential of this method for detecting orbital climate forcing in continental successions.

International audience; Pollen and paleomagnetic analysis of the Rubielos de Mora-1 core (Rubielos de Mora basin, NE Spain) has been carried out with the aim of reconstructing floral, vegetational and climatic changes within an accurate time framework. Based on biostratigraphic information, the magnetostratigraphy (ATNTS04) resulting in an age of Early Miocene for the cored sedimentary sequence. The high percentages of thermophilous taxa and the diverse subarid flora in the pollen spectra points to a very dry subtropical climate with a marked seasonality, reflecting the onset of the Miocene climatic optimum. On the other hand, taxa with high water requirements (riparian) are also abundant. Alternation in pollen taxa (thermophilous vs. mesothermic–riparian), coincide with sedimentological changes, which are related to lake level fluctuations and vegetation changes. In turn, the vegetational pattern indicates cyclic changes in temperature and precipitation which is controlled by astronomically forced obliquity cycles.