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The mixed carbonate-siliciclastic ramps of the Dauphinois-Provençal domain in northwest Italy are characterized by a common development process during the Paleogene. Spectral gamma-ray (SGR) analysis indicates the concentration of potassium (K), uranium (U), and thorium (Th) in the total gamma-ray signal, permitting the identification of subtle stratigraphic compositional trends, sedimentary minerals, paleoclimatic conditions, and the individualization of lithofacies characters through the stacking pattern cycles. This study integrates known lithological and fossil content analysis of the section with new independent data from the spectral gamma-ray (SGR) to explore the paleoclimate and stacking patterns for defining large-scale depositional cycles along a Paleogene succession in the southwestern Alps. The differences between the outcropping Microcodium Formation and the Capo Mortola Calcarenite Formation are indicated by the SGR, conventionally shown on a linear scale as American Petroleum Institute (API) units, i.e., Th/U, and Th/K ratios. Our data indicate lithofacies associated with normal marine to continental conditions and the presence of abundant smectite, rather than kaolinite, suggesting that the prevailing climate was characterized by prolonged dry periods. Furthermore, the SGR (API) reconstruction of the overall short cycles reflects a progradational and/or retrogradational stacking geometry that accumulated throughout the whole succession. However, the use of the derivative trend analysis (DTA) of the SGR indicates the establishment of long cycles in both formations. The short cycles observed in the Capo Mortola Calcarenite Formation are of particular importance because they characterize the marine transgression of the middle-upper Eocene, transgressive upon the Upper Cretaceous beds, and permit pinpointing the onset of the drowning ramp, which can be correlated regionally with sections spanning from the French-Italian Maritime Alps to the France-Switzerland border. • Paleogene climate reconstruction using spectral gamma-ray emissions. • Th/K and Th/U ratios indicate specific sedimentary conditions. • Alternation of humid and arid climates could be detected along the section. • The process of ramp drowning is accommodated by short-cycle stacking patterns. • Derivative trend analysis (DTA) supported long cycles recognition. [ABSTRACT FROM AUTHOR]

Avian traces occurring in Pleistocene aeolianite and beach deposits are rare and relatively poorly known, despite being good paleoenvironmental indicators. Passeriform and raptorial birds are especially rare in the track fossil record. Exceptional tracksites were found in the Malhão formation, a Pleistocene coastal aeolianite unit from the SW mainland Portugal, with subunits in the interval ∼187 to ∼27 ka. Two new forms of avian traces were identified, Corvidichnus odemirensis and Buboichnus vicentinus - attributed to the locomotion of Western jackdaw and the locomotion and predation/feeding behaviour of a large Eagle-owl. The last trace fossil may correspond to the first evidence of a raptorial bird-prey interaction found in action in the fossil record. Typical shorebird tracks and trackways attributed to gulls (Laridae) and curlews, and others tentatively compared with Rallidae, such as Eurasian coot, are also discussed within the aeolianite ichnoassemblages. The tracks here described are the first avian ichnotaxa from the Pleistocene of Europe. • Two new bird tracksites are described from the Middle-to-Late Pleistocene coastal aeolianites of SW Portugal. • Corvidichnus and Buboichnus vicentinus igenn. nov. record behaviors of western jackdaw and a large eagle-owl. • Passeriform and raptorial birds are especially rare in the track fossil record. • A trace fossil of raptorial bird-prey interaction is described for the first time. • These tracks are the first avian ichnotaxa from the Pleistocene of Europe. [ABSTRACT FROM AUTHOR]