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The Arda River marine succession, cropping out in western Emilia (northern Italy) represents an excellent site to study past ecosystems dynamics in the frame of Early Pleistocene climate change and tectonic activity. This one-day excursion leads the participants to discover the palaeoclimatic and palaeoenvironmental evolution of the Lower Pleistocene Arda River marine section, unraveled through an integrated use of sedimentological, palaeoecological (molluscs and trace fossils) and geochemical tools. Upsection, the succession was deposited in progressively shallower water and colder climate during phases of advance of fan deltas affected by hyperpycnal flows. It culminates at the top with clast supported alluvial conglomerates and freshwater/terrestrial biota indicating a sea level drop and the establishment of a continental environment. It is very rich in fossils: in the marine part molluscs, brachiopods, corals and echinoderms, besides well preserved trace fossils, are abundant; whereas in the continental part a mammal fauna and freshwater/terrestrial molluscs are occasionally found. Sclerochemical analyses undertaken on bivalve shells indicate that seawater temperature seasonality was the main variable of climate change within the study area during the Early Pleistocene. In particular, strong seasonality and low winter palaeotemperatures were assumed to be the main drivers for the widespread establishment of Arctica islandica populations in the palaeo-Adriatic Sea around 1.80 Ma. During the excursion not only fossils are shown, but also interesting biocalcarenitic bodies with a complex geometry cropping out in the town of Castell’Arquato. The excursion is complemented by the visit to the Giuseppe Cortesi geological and palaeontological museum, housing vertebrate and invertebrate fossil collections.

International audience; Based on mapping of laterally traceable stratigraphic discontinuities, we propose a high-resolution allostratigraphic scheme for one of the world's foremost fossil marine vertebrate Lagerstätten: the lower Miocene strata of the Chilcatay Formation exposed along the Ica River near Zamaca, southern Peru. Measured sections combined with 1:10,000 scale mapping of a 24 km 2 area provide an overview of the stratal architecture, as well as a general facies framework and interpretation of the various depositional settings. As a whole, the Chilcatay alloformation is bounded by the CE0.1 unconformity at the base and the PE0.0 unconformity at the top. An internal Chilcatay surface, termed CE0.2, splits the alloformation into two distinct allomembers (Ct1 and Ct2). The Ct1 allomember comprises three facies associations recording deposition in shoreface, offshore, and subaqueous delta settings. The Ct2 allomember comprises two facies associations, recording deposition in shoreface and offshore settings. Using these data, we place the rich marine vertebrate assemblage in a precise spatial and stratigraphic framework. The well-diversified vertebrate assemblage is dominated by cetaceans (mostly odontocetes) and sharks (mostly lamniforms and carcharhiniforms); rays, bony fish, and turtles are also present. Taxonomic novelties include the first records of baleen whales, platanistids, and eurhinodelphinids from the Chilcatay Formation. ARTICLE HISTORY

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.

The Arda River marine succession (Italy) is an excellent site to apply an integrated approach to paleoenvironmental reconstructions, combining the results of sedimentology, body fossil paleontology, and ichnology to unravel the sedimentary evolution of a complex marine setting in the frame of early Pleistocene climate change and tectonic activity. The succession represents a subaqueous extension of a fluvial system, originated during phases of advance of fan deltas affected by high-density flows triggered by river floods, and overlain by continental conglomerates, indicating a relative sea level fall and the establishment of a continental environment. An overall regressive trend is observed through the section, from prodelta to delta front and intertidal settings. The hydrodynamic energy and the sedimentation rate are not constant through the section, but they are influenced by hyperpycnal flows, whose sediments were mainly supplied by an increase in Apennine uplift and erosion, especially after 1.80 Ma. The Arda section documents the same evolutionary history of coeval successions in the Paleo-Adriatic region, as well as the climatic changes of the early Pleistocene. The different approaches used complement quite well one another, giving strength and robustness to the obtained results.

We present the geological map at 1:25,000 scale of the Plio-Quaternary Paganica-San Demetrio-Castelnuovo Basin corresponding to the epicentral area of the 6 April 2009 Mw: 6.29 L’Aquila earthquake. The map focuses on the relationships between the active tectonics and the Plio-Quaternary deposits and on the early evolution of this continental basin. Fine-scale geological field surveys, coupled with paleontological data, facies analyses, well logs and geophysical data interpretation, allowed to better understand the stratigraphy and to review the previously described stratigraphical units, resulting in the definition of eight synthems, spanning from late Piacenzian to Holocene. More precisely, the occurrence of a Caspiocypris species flock (ostracods) at the base of the sedimentary infill of the basin formed by a lacustrine system, suggests that the onset of deposition started in the late Piacenzian. The lacustrine system disappeared around the Gelasian/Calabrian transition, while the subsequent evolution of the sedimentary basin was characterized by the presence of fluvial and alluvial fan systems progressively entrenched into the lake deposits. The results of the above-mentioned activities are summarized in the attached geological map, where the Plio-Quaternary synthems and the active normal faults accountable for the significant seismicity were highlighted.

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.

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.