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Abstract: Tuscany (Central Italy) is a key area for studying the Messinian Salinity Crisis and overlying Lower Pliocene deposits due to the high number and excellence of the outcrops. Although the Miocene/Pliocene transition is well exposed and suitable for detailed analyses, a high-resolution integrated stratigraphic study of such a crucial time span for the geological history of the Mediterranean has never been attempted. In the Fine Basin (Central Tuscany), the Cava Serredi section is one of the best exposures of the upper Messinian–Lower Pliocene transition of the Northern Apennines. The Miocene/Pliocene boundary corresponds to a surface separating thinly laminated lacustrine (“Lago-Mare”) marls from homogeneous circalittoral to upper bathyal marly clays. Detailed quantitative micropalaeontological analyses have been performed on 111 samples from the 22m-thick Lower Pliocene succession. They resulted in the improvement of the biostratigraphic resolution of the basal Zanclean interval due to the recognition of several chronologically constrained bioevents typical of the Mediterranean region and based on benthic and planktonic foraminifera and calcareous nannofossils. Moreover, to unravel cyclical patterns of deposition, and given that the investigated succession shows no evident lithological pattern, micropalaeontological analyses have been coupled with calcium carbonate content variations. The latter revealed more-regular fluctuations, which are especially evident if the exclusive contribution of the planktonic foraminifer fraction (PCaCO3) is considered. Spectral analysis of the CaCO3 curve indicates that sedimentation occurred under the control of Earth''s precession. This datum is also confirmed by the cyclical patterns of Neogloboquadrina acostaensis and Sphenolithus spp. among foraminifers and nannofossils, respectively. According to the proposed cyclostratigraphic and astrochronological reconstruction, the Lower Pliocene interval of the Cava Serredi section consists of eight precession-controlled cycles ranging from the i-cycle 510 (5.33Ma) to the i-cycle 494 (5.16Ma). Finally, the comparison with other astronomically calibrated sections, including the Zanclean GSSP (Eraclea Minoa, Sicily), allowed us to prove the completeness of the basal Zanclean interval of the study section and to state that Pliocene re-flooding after the Messinian Salinity Crisis occurred synchronously with respect to other deeper sectors of the Mediterranean Basin. [Copyright &y& Elsevier]

Abstract: This study has the aim of dating the latest Miocene Hominoid Oreopithecus bambolii bearing succession of the Baccinello–Cinigiano Basin (BCB) in southern Tuscany (Italy). Since the 1960s biochronology has been the source for rough age estimations. Geochronological techniques have started to provide significant time constraints after the absolute dating obtained from a single point in the BCB, where a relatively thick and continuous lithostratigraphic record is found together with a succession of several mammal sites. Chronological control of the sedimentary succession and age range of Oreopithecus faunal assemblage has nowadays only been possible with the characterization of the magnetostratigraphy of the BCB sedimentary succession. This study demonstrates that: i) the oldest Oreopithecus bearing sediments in BCB (V1) has an age older than 8.1Ma; ii) the IGF 4883V Oreopithecus from Trasubbie creek has an age of 8.1–7.7Ma; iii) the youngest Oreopithecus remains (from the so called V2 assemblages) have an age between 7.1 and 6.7Ma; iv) the Oreopithecus chronologic range within the BCB is about 1.5Ma long bracketed between 8.3 and 6.7Ma; v) the post-Oreopithecus faunal complex V3-bearing deposits, likely to have an age between 6.7 and 6.4Ma, belonging to the very early MN13 unit (early Messinian); and finally, vi) Oreopithecus is confirmed to be the youngest dryopithecine record from Eurasia, extending his last occurrence into the early Messinian. [Copyright &y& Elsevier]

Abstract: The astronomically tuned marls of the Monte Gibliscemi section, Sicily, constitute an archive to trace the late Miocene palaeoenvironmental conditions (~9.7–7.0Ma) in North Africa. Here we have utilised carbonate content and Al-normalised geochemical proxies to trace changes in terrigenous source area and bottom-water ventilation. The terrigenous input into the section is dominated by North African river systems draining into the Eastern Mediterranean. The proxy parameters indicate that the palaeoenvironmental conditions in North Africa were humid from 9.5Ma onward with high fluvial input to the Mediterranean. Increases in the Si/Al and Mg/Al ratios occurred from 8.4 to 8.2Ma and from 8.05 to 7.75Ma, with maximum values similar to those of Messinian diatomites. These peaks indicate conditions of enhanced biosiliceous productivity and the presence of authigenic clay formation. Sluggish water circulation in the Mediterranean during those times is inferred from the Mn/Al and V/Al behaviour. Late Miocene changes of the Betic (southern Spain) and Rifian (Morocco) Mediterranean–Atlantic gateways are interpreted as the driving force for the changes in water circulation and the transgression associated with the opening of the Rifian corridor is interpreted to occur at 7.8Ma. [Copyright &y& Elsevier]

Abstract: Benthic foraminifera from seep carbonates and from enclosing non-seep marls present within Miocene formations in the Northern Apennines (Italy) were investigated as proxies of methane seepage in the marine environment. Negative δ13C values of benthic foraminifera from these seeps indicate unambiguously the local influence of CO2 produced by microbial anaerobic methane oxidation on the benthic ecosystem. Calcareous species living within methane seeps display δ13C values ranging from −9.04 to −25.74‰ PDB, whereas in the coeval surrounding marls the same species display δ13C values from −1.54 to 0.62‰ PDB. Different species (Cibicidoides kullenbergi, C. pachyderma, Siphonina rethiculata, Planulina wuellestorfi, Bolivina miocenica, Brizalina dilatata, Vulvulina pennatula, and Cibicides praecinctus) in different seep carbonates indicate that benthic foraminifera, independently of the taxa and of microhabitat preferences, have more negative δ13C values than those found in the enclosing marls. Therefore each species represents a potential proxy for past seafloor methane emissions. In addition to the calcareous species, the agglutinated species Vulvulina pennatula displays −27.5‰ PDB in seep carbonates against −2.69‰ PDB in the enclosing marls. This suggests that the species utilized strongly 13C depleted carbonate particles from authigenic carbonate precipitation during the mineralization of their tests. [Copyright &y& Elsevier]

Abstract: A leaf physiognomic analysis has been carried out on 980 specimens of Messinian leaves collected during the last three decades of the 20th century from the Gessoso Solfifera Formation (Messinian, Late Miocene) in NW Italy. The material is stored at the F. Eusebio Museum of Alba, and originates from a few sites located in close proximity to each other in the valley of the Tanaro River near Alba. According to recently published age models, the studied plant-bearing sites can be dated between 6.0 and 5.7 Ma. The physiognomic analysis was preceded by a taxonomic one, which allowed separation of 74 to 77 dicotyledonous taxa (morphotypes). The botanical affinity of a large proportion of the taxa is not yet defined, because they either belong to the so-called “leguminosoid” types or consist of entire-margined leaves with a coriaceous texture, whose affiliations with a known plant family are not definable solely on the basis of gross morphology. Several recently published univariate and multivariate correlations between climate and leaf physiognomy were applied to the individual floras in order to estimate selected palaeoclimatic parameters. The results obtained for the two richest assemblages, as well as the combined flora from all localities, point to warm-temperate and humid palaeoclimatic conditions, also indicated by the taxonomic composition of these floras. One other assemblage, which consists of fewer taxa, provides significantly lower temperature and precipitation estimates. However, in this case, it is rather likely that the estimates have been influenced by the low number of taxa, caused by taphonomic biases, reducing the representation of entire-margined taxa. Our results imply that at least some existing leaf physiognomic techniques can reliably be used for the reconstruction of palaeoclimatic conditions based on floras from Europe, although previous data from other European floras suggested that some of these methods may produce erroneous results. [Copyright &y& Elsevier]

Abstract: Mazza and Rustioni [Mazza, P.P.A., Rustioni, M., 2008. Processes of island colonization by Oligo-Miocene land mammals in the central Mediterranean: New data from Scontrone (Abruzzo, Central Italy) and Gargano (Apulia, Southern Italy). Palaeogeogr. Palaeoclim. Palaeoecol. 267 (3–4), 208–215.] suggest that land bridges played an important role in the colonization of the Abruzzo–Apulian bioprovince, as shown by the fossil vertebrates from Scontrone and Gargano. Would they have been able to demonstrate that land bridges indeed played a role in the dispersion of mammals, this would have implied that we had to rethink the modes of colonization for many other isles and rewrite our theories on island biogeography. Unfortunately, their evidence falls short, and even though their paper provides new insights in the history of the insular faunas of the Apulia platform, there is no reason to assume that land bridges played any role in the colonization of these islands. [Copyright &y& Elsevier]