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The 10Be/9Be ratio is commonly employed as a tool for establishing the stratigraphic position of paleomagnetic excursions and reversals whenever the traditional paleomagnetic approach fails to provide conclusive results. In particular, it is held that 10Be production rates in the atmosphere depend on the strength of the Earth’s magnetic field, and the fallout and deposition of cosmogenic beryllium at the surface happen on a very short time scale. However, investigations performed on terrestrial and marine successions demonstrate that the 10Be record and the paleomagnetic signal are often asynchronous. Mechanisms that control the conveyance and deposition of cosmogenic 10Be to the seafloor are still ambiguous and poorly documented. Here, we discuss the dynamics of 10Be in a central Mediterranean marginal marine depositional scenario characterized by a pervasive terrigenous influx. Our data show that a very close correlation exists between 10Be concentrations and the local proxy of rainfall rates and regimes (pollen), indicating that a considerable 10Be transport from the mainland may occur in response to the remobilization of terrestrial reservoirs during periods of increased runoff. Superimposed is a dynamic oceanographic setting that further controls the preservation potential of 10Be at the bottom, in terms of changing water chemistry and/or composition of the sedimentary flux to the seafloor. Results of our investigation suggest that, in particular environmental and depositional settings, the interplay between climate, terrigenous yield and oceanography may jeopardize the sedimentary depiction of the meteoric 10Be contribution, thus challenging the use of 10Be for tracking the stratigraphic position of geomagnetic reversals.

The genus Protosphyraena is known mainly from partial remains, consisting of isolated blade-like teeth, conical rostra and scythe-like pectoral fins. This paper provides a new insight into partial specimens of the genus Protosphyraena from the Cretaceous of NE Italy, housed in historical collections from local paleontological museums and previously poorly known to the international scientific community. The specimens are referred to the species Protosphyraena ferox, based on the morphology of the pectoral fin. This attribution is consistent with the paleobiogeographic distribution and stratigraphic range of this taxon. The Italian material provides new information about the distribution in time and space of Protosphyraena, which is relatively poorly known despite being an iconic taxon. The Italian remains, although fragmentary, contribute to fill a gap in the central Tethys record of the genus, whose range probably extended worldwide, considering also the genus Australopachycormus and its profound (possibly congeneric) similarities., Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy), Vol 123, No 3 (2017)

Nel riempimento detritico di un inghiottitoio ubicato sotto Monte Castello (Croara) sono state rinvenute ossa fossili di Mammiferi (tra cui bisonte, marmotta, ermellino, capriolo e un colossale cervo, il Megacero) e pollini dell’ultimo Periodo Glaciale; il che testimonia che questi sedimenti detritici hanno un’età di 15.000 - 20.000 anni (vedi Finestra “L’inghiottitoio inattivo della ex Cava a Filo”, in questo volume). Tale età è confermata da datazioni al radiocarbonio. Alla base del riempimento detritico si trova un crostone alabastrino databile a circa 25.000 anni (Pasini, 1970). Ovviamente l’escavazione di tale inghiottitoio è più antica della deposizione del suo riempimento (il più antico datato nel Bolognese); da cui si desume che le grotte bolognesi si sono formate più di 25.000 anni fa . Fino ai primi anni novanta si riteneva che le grotte dell’Emilia-Romagna si fossero formate durante un unico ciclo carsico, sviluppatosi nelle ultime decine di migliaia di anni. Ma successivamente, in una cava di gesso vicino a Brisighella (Cava Monticino, Vena del Gesso Romagnola, circa 45 km a SE di Bologna), sono state osservate piccole cavità carsiche riempite da sedimenti contenenti vertebrati terrestri fossili (tra cui mastodonti, scimmie, rinoceronti, antilopi, iene, varani e coccodrilli) che vivevano lì durante le fasi finali del Messiniano. Da ciò si desume che localmente si è verificata un’emersione alla fine del Messiniano (da 5,6 a 5,4 milioni di anni fa: Sami 2007), durante la quale sono state escavate le cavità carsiche suddette: infatti i fenomeni carsici (doline, grotte ecc.) non si possono sviluppare in una certa zona se essa è interamente sommersa dal mare, ma solo se la zona è emersa. Quindi questo antico ciclo carsico ha un’età di circa 5,6 - 5,4 milioni di anni. Questi ed altri dati inducono alla seguente ricostruzione degli eventi geologici per la zona di Brisighella: - tra 5,96 e 5,6 milioni di anni fa ingenti volumi di gesso si depositarono sul fondo di lagune soprasalate, formando strati suborizzontali; - tra 5,6 e 5,4 milioni di anni fa si verificò una prima emersione dei gessi, i cui strati divennero moderatamente inclinati; l’area venne popolata da faune terrestri tardo-messiniane; questa emersione consentì lo sviluppo di un primo ciclo carsico, che originò le piccole cavità suddette; - tra 5,4 e 5,3 milioni di anni fa l’area venne occupata da paludi e lagune; - tra 5,3 e 0,8 milioni di anni fa l’area fu nuovamente sommersa da un mare mediamente abbastanza profondo; - negli ultimi 0,8 milioni di anni il sollevamento appenninico causò la definitiva emersione dell’area, una più elevata inclinazione degli strati gessosi, e consentì lo sviluppo di un secondo ciclo carsico, molto più accentuato del primo. Quindi nei gessi di Brisighella si sono avuti due cicli carsici: uno tardo-messiniano (circa 5,6 - 5,4 milioni di anni fa), ed uno posteriore a 800.000 anni fa. Fino a poco tempo fa il primo ciclo carsico era noto solo nel Brisighellese. Prima di proseguire è opportuno ricordare che i sedimenti deposti dalle correnti sotterranee, come pure quelli deposti dalle acque marine e lagunari, sono di regola suborizzontali. Tra il 2008 ed il 2012 è stata studiata una galleria carsica freatica - la “Galleria dei Quattro” -, intercettata casualmente da una cava di gesso presso Zola Predosa (circa 10 km ad Ovest di Bologna), in cui gli strati gessosi sono inclinati verso NE di 45°-50°. La “Galleria dei Quattro”, precedentemente sconosciuta, ha un diametro di 4-5 m ed è completamente occlusa da sedimenti stratificati. Questi sedimenti - consistenti in argille, talora litificate (cioè trasformate in roccia compatta), sabbie a costituenti gessosi e blocchi di varie rocce - sono stati depositati da grossi torrenti sotterranei. I sedimenti contengono Foraminiferi e Nannofossili (entrambi microorganismi marini) di età serravalliana (da 13,82 a 11,608 milioni di anni fa); questi microfossili sono stati “rimaneg...

Hemipelagic dark limestones within calciturbiditic deposits at Monte Solane in the western Lessini Mountains of northern Italy yield a fish fauna dominated by stomiiforms. A minor component of the fossil assemblage is represented by a macroalgal non-calcareous flora associated with rarer terrestrial components including few angiosperm leaves and seeds. Micropaleontological (foraminifera, dinoflagellate cysts), sedimentological and geochemical proxies (TEX86) indicate a deposition of the fossil-bearing bed in a hypoxic to possibly anoxic, warm, restricted basin. High-precision dating based on rich foraminiferal and calcareous nannoplankton content allows ascribing the site to the upper part of the Ypresian (Lower Eocene). The site is slightly older than the Ypresian worldwide-famous shallow-water Bolca Konservat-Lagerstatte located in the same region. Convergent paleoenvironmental clues based on both microfossils and ichthyofauna indicate that the sediments were deposited in the upper bathyal zone, probably between 300 and 600 m. Solane is therefore one of the rare and precious Eocene Lagerstdtte to have fossilized in a deep marine setting. The site contains the oldest Cenozoic record of an ichthyofauna dominated by meso-bathypelagic taxa. (C) 2014 Elsevier B.V. All rights reserved.

A high-resolution, integrated stratigraphic framework (stable isotope stratigraphy, standard calcareous nannofossil and foraminiferal biostratigraphy, magnetostratigraphy) together with geochemical and rock magnetic properties analyses of a complete and well-preserved succession at Contessa Valley (Gubbio, central Italy) have offered an excellent opportunity to identify and constrain the Palaeocene to early Eocene hyperthermals and carbon isotope excursions (CIEs). In addition, we provide the first evidence in the Tethys Ocean of CIEs, previously identified in the Pacific, Atlantic and Southern Oceans, highlighting their global significance and of some unknown CIEs. Their characteristics are compared with those reported for deep-sea cores and other land-based sections to test whether the signature associated with CIEs documented in our composite section might give evidence for tracing them over wider areas. The Contessa composite section thus represents a reference succession also for insight into the magnetobiochronostratigraphy and the magnitude of early Palaeogene hyperthermals and CIEs.

A new fossiliferous site with marine fishes and plants was recently discovered at Monte Solane (Verona Province, Veneto region, northern Italy). At least nine previously undescribed teleost fish taxa, most of them represented by mesopelagic fishes, were found. The stomiiform Gonostomatidae gen. indet. cf. Scopeloides strongly dominates the assemblage. Based on calcareous nannoplankton and larger foraminifera content, the Monte Solane beds are ascribed to the lower Eocene (upper Ypresian). The fish-bearing sediments of Monte Solane were likely deposited in a middle-outer platform environment, close to emerged land.

Calcareous nannofossil, mineralogical and geochemical data are presented from the expanded Paleocene-Lower Eocene Forada section in the Venetian Pre-Alps. The short-lived Paleocene Eocene Thermal Maximum (PETM) is characterized by profound and temporally constrained changes among calcareous nannoplankton assemblages, triggered by global modifications of the ocean-atmosphere system. The Calcareous Nannofossil Excursion Taxa (CNET) represent transient adaptations to changes in the chemical (nutrients, CO2, pH) and temperature structure of surface waters typifying the PETM. Oligotrophic taxa, such as Sphenolithus, Zygrhablithus, Octolithus and Fasciculithus, exbihit a sharp decrease in abundance, whereas reworked forms show a sharp increase. These changes reflect a response to the modified environmental conditions, characterized by sharp increase in nutrient availability. This increase likely resulted from a huge terrigenous input, suggesting that the siliciclastic pump was intensified by enhanced weathering and runoff. The high correlations between mineralogical/geochemical data and calcareous nannofossil fluctuations is consistent with this scenario. Highly-resolved age estimations are established for several calcareous nannofossil biohorizons based on cyclostratigraphy

The central part of the Piave River valley in the Venetian pre-Alps of NE Italy exposes an expanded and continuous marine sediment succession that encompasses the Paleocene series and the Paleocene to Eocene transition. The Paleocene through lowermost Eocene succession is > 100 m thick and was deposited at middle to lower bathyal depths in a hemipelagic, near-continental setting in the central western Tethys. In the Forada section, the Paleocene succession of limestone-marl couplets is sharply interrupted by an similar to 3.30-m-thick unit of clays and marls (clay marl unit). The very base of this unit represents the biostratigraphic Paleocene-Eocene boundary, and the entire unit coincides with the main carbon isotope excursion of the Paleocene- Eocene thermal maximum event. Concentrations of hematite and biogenic carbonate, delta(13)C measurements, and abundance of radiolarians, all oscillate in a cyclical fashion and are interpreted to represent precession cycles. The main excursion interval spans five complete cycles, that is, 105 +/- 10 k.y. The overlying carbon isotope recovery interval, which is composed of six distinct limestone-marl couplets, is interpreted to represent six precessional cycles with a duration of 126 +/- 12 k.y. The entire carbon isotope excursion interval in Forada has a total duration of similar to 231 +/- 22 k.y., which is 5%-10% longer than previous estimates derived from open ocean sites (210-220 k.y.). Geochemical proxies for redox conditions indicate oxygenated conditions before, during, and after the carbon isotope excursion event. The Forada section exhibits a nonstepped sharp decrease in delta(13)C (-2.35%) at the base of the clay marl unit. The hemipelagic, near-confinental depositional setting of Forada and the sharply elevated sedimentation rates throughout the clay marl unit argue for continuous rather than interrupted deposition and show that the initial nonstepped carbon isotope shift was not caused by a hiatus. A single sample at the base of the unit lacks biogenic carbonate. Preservation of carbonate thereafter improves progressively up-section in the clay marl unit, which is consistent with a prodigiously abrupt and rapid acidification of the oceans followed by a slower, successive deepening of the carbonate compensation depth. Increased sedimentation rates through the clay marl unit (approximately the main interval of the carbon isotope excursion) are consistent with an intensified hydrological cycle driven by super-greenhouse conditions and enhanced weathering and transport of terrigenous material to this near-continental, hemipelagic environment in the central western Tethys. The sharp transition in lithology from the clay marl unit to the overlying limestone-marl couplets in the recovery interval and the coincident shift toward heavier delta(13)C values suggest that the silicate pump and continental weathering, the cause of the enhanced terrigenous flux to Forada, stopped abruptly. This implies that the source of the light CO(2) ceased to be added to the ocean-atmosphere system at the top of the clay marl unit.