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The early-middle Eocene (ca. 56-41 Ma) is recorded in the pelagic Scaglia Rossa and Variegata Formations of the Umbria-Marche Basin (central Italy). Geochemical and magnetostratigraphic alignment between the Bottaccione section (Gubbio, central Italy) and the Smirra core (Cagli, central Italy) allows us to generate a continuous and wellpreserved new record that, combined with previously published data from the same area, creates a continuous high-resolution record from the Paleocene-Eocene thermal maximum (ca. 56 Ma) to the lower part of chron C21n. Comparison with carbon isotope records from Ocean Drilling Program Sites 1258 and 1263 reveals a satisfactory match, providing further evidence of the global significance of the long-term trend and superposed perturbations captured by the δ13C records. The identification of astronomically forced geochemical cycles allows us to develop a 405 k.y. tuned age model, thereby extending the astrochronology from ca. 56.0 to ca. 47.5 Ma. Marine magnetic anomaly profiles from major oceanic basins characterized by high seafloor spreading rates were used to independently test the astronomical polarity time scale associated with our tuning, as well as other polarity time scales. Our age model suggests the existence of periods of relatively constant seafloor spreading rates separated by rapid changes, while the other time scales generate more gradual variations and also include large and short-term deviations in spreading rates that occur simultaneously in different oceanic basins, implying errors in polarity reversal ages. The Umbria- Marche age model further contributes to the closure of the middle Eocene gap in the astronomical time scale.

International audience; An integrated study of multiple geochemical proxies (δ13Ccarb, δ13Corg, TOC,HI,CaCO3, trace elements/Al ratios) ofthe late Aptian–early Albian oceanic anoxic event (OAE) 1b has been performed on the pelagic sedimentarysequence of Poggio le Guaine (Umbria–Marche Basin, central Italy). A comparison of the newly collected stableisotope carbon curve with the records from the Vocontian Basin (SE France), DSDP Site 545 and Hole 1049Cprovided a reliable and precise identification of the four main prominent black shale levels (113/Jacob, Kilian,Urbino/Paquier and Leenhardt) that characterize the OAE 1b. The studied record shows an increase in the marineorganic carbon accumulation rate, in particular in the 113/Jacob and Urbino/Paquier levels. In the other blackshales, TOC values are b1%, with evidence of degraded marine organic matter. Completely anoxic conditionswere never established during the sediment deposition, although evidence of oxygen depletion at the bottomof the basin is clearly documented by the distribution pattern of redox-sensitive trace metals. The results suggestan increase in organic carbon burial rates during the OAE 1b due to the effect of enhanced surface productivity, assupported by a major increase in Ba/Al, and reduced bottom water ventilation.Notably, the Kilian and Urbino/Paquier levels fromthe PLG section are characterized by the absence of correlativeshifts in δ13Ccarb and δ13Corg. The increase in the δ13Corg values in these levels is explained by an increase in therelative contribution of 13C enriched marine planktonic archaeal biomass, while the concomitant negativeexcursions recorded in the δ13Ccarb could reflect a major contribution of isotopically light terrestrial carbonateions from increased continental runoff during documented more humid conditions.

Il Mar Mediterraneo è un bacino semichiuso caratterizzato da un'elevata pressione antropica fin dall'antichità. Sulle coste insistono centri urbani di dimensioni notevoli, i cui effetti, in termini di anomalie geochimiche e livello di inquinamento, sono ancora poco studiati. Obiettivo della Campagna Oceanografica ANOMCITY_2012 era quello di studiare gli effetti dell'inquinamento da metalli pesanti in aree marine antistanti un numero discreto di siti ad elevato impatto antropico (centri urbani e Siti di Interesse Nazionale), ovvero: Gioia Tauro, Milazzo, Augusta, Gela, Catania e Taranto (le condizioni meteo estremamente difficili non hanno permesso il campionamento dell'area antistante Brindisi), al fine di valutarne lo stato reale della contaminazione, le sua storia e possibile evoluzione. La scelta delle aree investigate è stata guidata dalla specificità della tipologia di inquinamento propria di ogni sito e soprattutto all'importanza, in termini quantitativi, di tale impatto su scala bacinale-regionale.