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We report 130 vertebrate fossils preserved as bony elements and the co-occurring assemblage of fish teeth and spines from the lower strata of the Pisco Formation exposed along the western side of the lower Ica Valley (East Pisco Basin, Peru). Geological mapping at 1:10,000 scale reveals that all these fossils originate from the Langhian–Serravallian P0 allomember. In the study area, P0 is up to ∼40 m thick and features a sandy lower portion, reflecting shoreface deposition, that fines upwards into a package of offshore silts. Marine vertebrates only occur in the lower sandy layers and include whales, dolphins, reptiles, birds, and bony and cartilaginous fishes. The reconstructed paleoenvironment is consistent with a warm-water, marginal-marine setting with a strong connection to the open ocean. This work helps to elucidate the rich yet still poorly understood middle Miocene portions of the Pisco Formation, and highlights the need to conserve this outstanding Fossil-Lagerstätte.

International audience; We present a geological map at 1:25,000 scale of the Plio-Quaternary L'Aquila-Scoppito intermontane basin (central Italy), which corresponds to the epicentral area of the 6th April 2009 L'Aquila earthquake (Mw: 6.29). The map is derived from geological field surveys at 1:5000 scale and takes into account previously published maps. It is supported by a fine-scale LiDAR digital elevation model, paleontological analyses, 14 C dating, well log analyses of deep boreholes, and geophysical data interpretation. By taking into account that the remarkable historical and present-day seismicity of the area is the result of its Plio-Quaternary geological evolution, the aim of this study is to produce a fine-scale geological map of the study area through a comprehensive analysis of the occurring Plio-Quaternary synthems and the tectonic processes that are taking place within it.

The lower Pliocene Belvedere Formation, cropping out in the Crotone Basin, southern Italy, exhibits a metre-scale to decametre-scale shallow-marine cyclicity that shares features of both high-frequency sequences linked to shoreline shifts and controlled by minor relative sea-level and/or sediment supply changes, and sedimentological cycles unrelated to shoreline shifts. In order to better understand the high-frequency sequence stratigraphic framework of this succession, an integration of sedimentological, micropalaeontological (micro-foraminifera assemblages) and mineralogical (heavy minerals abundance) data is used. From a sedimentological/stratigraphic point of view, wave-ravinement surfaces bounding high-frequency sequences, and associated substrate-controlled ichnofacies, are prominent in outcrop and document environmental and water-depth changes, whereas bedset boundaries separating sedimentological cycles have a more subtle field appearance and are only associated with changes of environmental energy. Moreover, condensed deposits are present only above wave-ravinement surfaces, and the high-frequency sequences bounded by these surfaces have a thickness that is an order of magnitude greater than that of the bedsets. Micro-foraminifera assemblages may change, and the content of heavy minerals usually increases, across wave-ravinement surfaces, whereas both parameters do not change significantly across bedset boundaries. The abundance of heavy minerals is systematically higher, with respect to the underlying and overlying deposits, in the condensed shell beds that overlie wave-ravinement surfaces. An integrated sedimentological, micropalaeontological and mineralogical approach represents a powerful tool to discriminate between wave-ravinement surfaces bounding high-frequency sequences and bedset boundaries, and in general to investigate at the intra high-frequency sequence scale. This integrated approach is expected to be very useful in the study of potentially all shallow-marine successions composed of small-scale cycles, in order to delineate a detailed sequence stratigraphic framework and understand the factors that controlled the cyclicity. This article is protected by copyright. All rights reserved.

During the Late Triassic the “Carnian Pluvial Event”, a global episode of climate change that involved increased rainfall and possibly global warming, a major crisis for carbonate producers is observed. In the western Tethys, the change in carbonate production led to a significant modification of depositional geometries of shallow water carbonate bodies. Sedimentary facies analysis coupled with quantitative 3D georeferenced field data acquisition of selected outcrops in the Cortina d’Ampezzo area (Dolomites, North-eastern Italy) reveal that the climatic event began before a drop of sea-level and caused the demise of km-scale microbial-dominated high-relief carbonate platforms that dominated the Dolomites region, and was followed by a period of coexistence of m-scale microbial carbonate mounds interlayered and laterally onlapped by arenaceous skeletal–oolitic grainstones. A subsequent sea-level fall brought to the definitive disappearance of microbialites, and shallow water carbonates switched to ramps dominated by oolitic–bioclastic grainstones. The crisis of high-relief shallow water carbonate platforms generated a geological surface similar to a drowning unconformity, although no transgression occurred. As the high-relief microbial-dominated carbonate platforms switched to gently inclined oolitic–skeletal–siliciclastic ramps, the neighboring basins were rapidly filled. The carbonate depositional systems turnover was associated with an increase in siliciclastic sediment input, in turn triggered by the onset of the Carnian Pluvial Event and only later to a drop of the sea-level. Results show that the evolution of the described carbonate systems of the Dolomites cannot be interpreted in the light of sea level changes only, pointing out that climate changes, and consequent ecological changes in the main carbonate producing biotas, can induce significant modifications in depositional geometries. The climatic change to more humid conditions precedes a sea-level drop in this Carnian case study.

The late Quaternary evolution of the Sele River coastal plain (Salerno Gulf, southern Italy) was investigated through integrated stratigraphical, chronological and palaeoecological analyses. The main environmental changes were ascribed to glacio-eustatic variations leading to rapid ingressions alternating with coastal progradations. The marked marine ingression of MIS 5.5 is testified by palaeoridges now cropping out 4 km inland at 11/13 m a.s.l. (Gromola palaeoridge). The eustatic minimum of MIS 2 is testified by lower shoreface deposits in the offshore core record and in the seismic profiles at 120/130 m below sea level. This prolonged sea-level fall was interrupted by at least three rapid sea-level rises, probably related to MIS 5.3, 5.1 and 3. The evidence of the first two sea level rises are represented by shoreface deposits in the inland S1 core (30 m thick, 3 m a.s.l., 1.5 km inland). The highstand of MIS 3 was identified by seismic profiles as onlapping marine deposits. The shore deposits at 100 m b.s.l were tentatively attributed to the lowstand of MIS 4. After the lowstand of MIS 2, the Sele Plain was newly flooded due to the rapid Post Glacial sea-level rise. This ingression caused the inland migration of a barrier-lagoon system and stopped at approximately 5.5 ky BP. From that moment the shoreline started prograding up to the present position probably due to the decrease in the sea-level rise rates and to the volcaniclastic supplies from the Neapolitan volcanoes, especially from the AD 79 Vesuvius eruption, also recorded in the subbottom chirp profiles.

The post-Miocene marine succession of the «Apricena horst» is described with the purpose to verify the chronostratigraphic constraints for the type-locality of the Pirro Nord Faunal Unit. The stratigraphic succession has been subdivided in four units bounded by ubiquitous unconformities with evidence of subaerial exposure. The two basal units (dated late Zanclean to at most early Piacenzian) are formally grouped in the Lago di Varano Fm. that on the whole consists of sediments ranging from lagoonal to circalittoral environments. Within the lowermost unit, a megabreccia is interpreted as the product of a tsunami event. The third unit, Gelasian in age, is informally cited as Calcari a Briozoi Fm. The last unit, the Early Pleistocene Serracapriola Fm., consists of siliciclastic deltaic sediments and represents the closure of the marine cycle. Conspicuous lateral facies and thickness changes, and the frequency of unconformities are the consequence of an intense synsedimentary tectonic activity developed in the frame of the southern Apulia foredeep closure. In the study area, such activity is documented by two E-W trending normal faults which, during Zanclean and at least the earliest Gelasian, controlled the Pliocene horst-graben system of the Apricena-Poggio Imperiale area.

The Plio-Pleistocene succession forming the infill of the Southern Apenninic foredeep in Molise is described, for the first time, in terms of sedimentological characteristics, and is compared with the stratigraphic framework reconstructed from adjacent areas. The vertical stacking of facies between Trigno and Fortore rivers shows an obvious “regressive” tendency from open marine to alluvial depositional systems. Specifically, offshore deposits (Montesecco Clays) display vertical transition to overlying offshore-transition (lower Serracapriola Sands) and nearshore (upper Serracapriola Sands) facies. This shallowing-upward succession is unconformably overlain by alluvial deposits (Campomarino Conglomerates). Detailed facies investigation of Serracapriola Sands enables identification of a wide spectrum of littoral deposits, forming a peculiar progradational beach sequence. This includes, from bottom to top, lower shoreface, upper shoreface and foreshore facies associations, with local development of backshore deposits. River influenced deposits are identified close to the boundary with the overlying Campomarino Conglomerates. The Plio-Pleistocene succession described in this work displays strong similarities with the stratigraphic framework traditionally reported from the northern and central sectors of the Apenninic (periadriatic) foredeep. Particularly, the stratigraphic boundary between Serracapriola Sands and Campomarino Conglomerates is interpreted to reflect the boundary between depositional cycles Qm and Qc, recognized at more northern locations. Despite lack of reliable chronological data, facies analogies with the coeval units suggest that Serracapriola Sands might represent the southern equivalent of the “yellow sand” facies cropping out extensively along the Apennines foothills, between Emilia-Romagna and Marche.

In the Mount Messapion area (Chalkida, Greece) a continuous and expanded section of Triassic/Jurassic (T/J) limestone is exposed. This section consists of a 710 m thick pile of shallowing-upward peritidal cycles; the persistence of the facies and the lack of paleoenvironmental changes across the T/J boundary allowed studying the distribution of shallow water microfossils. The T/J boundary is placed in the upper part of the section defined by correspondence with (i) the last occurrence of Triasina hantkeni, (ii) the abrupt disappearance of megalodontid faunas and (iii) the presence of Early Jurassic microfossil assemblages. This paleontological reorganization happens suddenly, it is not controlled by any facies change, and surprisingly, it seems to produce no evident modification in the vertical stacking pattern of the cycles. A detailed facies analysis, performed along a 290 m thick stratigraphic interval (60 m above the T/J boundary and 230 m below), allowed the recognition of peritidal cycles: five different elementary cyclothemes are described and their distribution along the section is given. This integrated stratigraphic study attempts to highlight the relationship between the changes of carbonate producers and sea level fluctuations across the T/J boundary., Rivista italiana di Paleontologia e Stratigrafia, Vol 114, No 3

Calcareous tufa deposits occurring in the Aniene and Simbrivio Valleys (Latium, Central Italy) between Vallepietra and Mandela- Vicovaro areas have been studied by means of morpho-geological mapping, mineralogical and facies analysis, malacofauna investigation, geo-archeological research and U/Th dating. The deposits of Subiaco and Mandela-Vicovaro have been studied in detail, because their formation has modified not only the geomorphic features of the two areas, but has strongly controlled and directed the human activity. A 15 m thick calcareous tufa body occurring in a bore drilled near Marano Equo, intercalated in a Paleoaniene alluvial deposits, has also been studied. After having examined the geological and structural pattern of the valley, controlled by apenninic (NW-SE) and antiapenninic (NE-SW) faults and by a complex hydrological system, that makes it one of the richest valleys in spring-waters of Latium (most of Roman aqueducts came from the Aniene Valley), the deposits of the different sectors are described. Calcareous tufa deposits, occurring in the Simbrivio Valley, connected to several cool springs issuing from the right, steep slope are described. The tufa deposits, prograding vertically and towards the valley bottom, interdigitate and often form highly vegetated terraces, on the front of which still active waterfalls, covered by moss and algae already partially calcified, occur. In the Aniene Valley, upstream of Subiaco very interesting examples of still active tufa deposits, forming fan-shaped bodies, prograding towards the river bed, occur. They are made mainly of phytomicrohermal and stromatolitic laminites, rich in leaf moulds, covered by a thick mat of algae, mosses, liverworts and other hygrophytes. Small barrage tufa deposits can also be observed. In the Subiaco area a tufa deposit, covering an area of about 1 km2, 70-80 m thick, occurs; it represents a barrage deposit, formed in the gorge at the outlet of the Subiaco basin, probably built up in correspondence to a morphological step of tectonic origin. Its basal portion is mainly made of palustrine, thinly laminated facies, rich in leaf moulds and vegetal frustules, grading upward to massive or grossly stratified, phyto- microhermal framework, containing well-developed large pools, filled with sandy-silty phytoclastic sediments of fluvio-lacustrine environment. The outer part of the deposit is partially covered by vertical hanging festoons and drapes of moss cascade lithofacies. The deposit has been terraced in three orders of terraces by the river, at present flowing in a narrow gorge in the Miocene substratum. The Ist order terrace surface is covered by a thick, pedogenized soil colluvium, rich in volcanic minerals, while the terraces of the IInd and IIIrd orders are covered by reddish-brown or brown soils, poor or devoid of volcanic minerals. In the Mandela-Vicovaro area a continuous calcareous tufa terrace extends along the Aniene gorge for about 3 km, up to 60-70 m thick. It formed as a barrage deposit near Vicovaro, where the emplacement of Middle Pleistocene volcanics, superimposed by younger, coarse alluvial sediments has produced a discontinuity in the river bed. As in the Subiaco deposit, the lower portion of the Mandela-Vicovaro one is composed of thinly stratified, laminitic and microhermal lithofacies, rich in leaf molds and vegetal frustules, of palustrine environment. They grade upward to massive phyto- microhermal litofacies, associated with large sandy-silty pools, rich in malacofauna. The surface of the terrace is covered by brown, calcareous soil. The terrace has been cut deeply as far as the Miocene substratum by the Aniene river and Licenza stream, its main right tributary. The sections of the terrace along the river are partially covered by waterfall moss lithofacies, forming vertical hanging drapes. The study of malacofauna contained in pool filling sands and silts referred the sediments to shallow freshwater, well vegetated environment, under temperate climate. Several Marano Equo, Subiaco and Mandela-Vicovaro samples have been dated by means of U/Th method which allowed the reconstruction of the chronostratigraphic evolution of the three calcareous bodies, referring the first to Late Pleistocene, the second to Upper Pleistocene-Early Holocene and the third to Late Glacial-Middle Holocene. Finally, on the basis of direct and bibliographic researches, the presence of Roman dams built up in the Subiaco area, forming upstream lacustrine basins, at present no longer existent, are discussed.