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This study presents, for the first time, a detailed quantitative reconstruction of winter (January) and summer (July) palaeotemperatures from the Late Pleistocene to Holocene transition in central Italy based on ostracod assemblages in an 8.59‐m‐long sediment core retrieved in Lake Trasimeno. Of 19 ostracod species recovered, 13 were calibrated according to their living temperature ranges, enabling us to reconstruct mean January and July temperature ranges using the mutual ostracod temperature range (MOTR) method. The occurrences of Cytheromorpha fuscata and Limnocythere suessenbornensis from 44 000 to 25 500 cal. a BP showed mean January temperatures at least 7 °C colder and mean July temperature at least 1 °C cooler in some intervals compared to present‐day temperatures. Comparison of the MOTR‐derived January minima curve with a Greenland oxygen isotope record (NGRIP) shows a remarkable correlation of warmer Greenland Interstadial and the colder Greenland Stadial events with clear peaks and troughs in the MOTR signal. These correlations were tested successfully by tuning the MOTR curve to the NGRIP record, resulting in an improved age‐depth model combining radiocarbon ages with MOTR tie points. The results demonstrate that a record of rapid climate change in the North Atlantic region is archived in lacustrine ostracod assemblages in central Italy. [ABSTRACT FROM AUTHOR]

The taxonomy of some non‐marine ostracod assemblages from the Dunarobba Fossil Forest area (south Tiberino Basin, Umbria, Italy) is discussed, adding to the scientific understanding of Piacenzian–Gelasian non‐marine ostracods in central Italy and providing a palaeoenvironmental reconstruction of the shallow coastal lacustrine environments of the Palaeolake Tiberino. The ostracod assemblages include Darwinula stevensoni, Vestalenula cylindrica, Candona (Candona) improvisa, Candona (Neglecandona) neglecta, Candona (Neglecandona) angulata, Candona (Neglecandona) paludinica, Caspiocypris basilicii, Caspiocypris tiberina, Candonopsis kingsleii, Cyclocypris ovum, Ilyocypris bradyi, Ilyocypris decipiens, Cypris mandelstami, Zonocypris membranae quadricella, Potamocypris fulva, Cyprideis crotonensis, Cyprideis rectangularis and two new species: Hemicypris lomastroi sp. nov. and Paralimnocythere turgida sp. nov. In addition to widespread European species, the ostracod assemblages contain some rare species that were previously known from the Pliocene Paludinian Beds of Serbia. A cluster analysis applied to the ostracod frequency matrix has lead to the identification of four separate assemblages that can be attributed to several ecological niches, including emerged hydrosols, ephemeral coastal pools and a littoral lacustrine margin, which suggest a complex coastal environment. [ABSTRACT FROM AUTHOR]

Ostracod assemblages from Lake Trasimeno (Umbria, central Italy), the largest endorheic lake in Italy, were investigated relating their species distribution and ecology to modern physical, chemical and biological parameters. Nineteen living species were collected in the lake (Darwinula stevensoni, Candona (Candona) candida, Candona (Neglecandona) angulata, Fabaeformiscandona fabaeformis, Pseudocandona marchica, Cypria ophtalmica, Ilyocypris gibba, I. salebrosa, I. getica, Cypridopsis vidua, Eucypris virens, Trajancypris clavata, Herpetocypris helenae, Heterocypris salina, H. incongruens, Isocypris beauchampi, Cyprideis torosa, Limnocythere inopinata, and L. stationis). All the identified species belong to the fresh-water Italian ostracod fauna but Cyprideis torosa is documented in an oligohaline athalassic lacustrine environment in Italy for the first time. The occurrence of Ilyocypris salebrosa represents the southernmost record in Italy and the westernmost in Eurasia. The recovery of Limnocythere stationis represents the westernmost record in Eurasia. The distribution of the different ostracods recovered in Lake Trasimeno is linked to the dominant physical and chemical parameters for each ecological niche. Physical and chemical data along with substratum type, grain-size and presence of aquatic macrophytes have been related to different ostracods using a multivariate analyses approach (NMDS, CCA, Spearman's rank correlation test). These results allow to differentiate several ecological niches within the lake and indicate that the main parameters affecting the ostracod assemblages are the aquatic macrophyte coverage, the Total Organic Carbon (TOC) and, to a lesser extent, temperature and type of substrate. Cyprideis torosa and Candona (Neglecandona) angulata have been recovered both in the distal part of the lake and in the lakeshore area. In both cases they are associated with scarce or absent aquatic macrophytes and low amounts of TOC. The alternate dominance of these two species in the distal deeper assemblages seems to be mainly linked with the bottom oxygen availability, being C.(N.) angulata dominant in the most oxygen-depleted sediments and C. torosa dominant in higher oxygen conditions. Along the lakeshore area they are often discovered together with other prevailing species, such as Cypridopsis vidua that is common in very shallow to shallow (20-140 cm) sites with high TOC content, abundant macrophytes and algae, and Limnocythere inopinata, which dominates slightly deeper areas (around 150-210 cm) where the previous species are almost absent. The Spearman's rank correlation test showed significant positive correlation between some ostracods and macrophyte species. [ABSTRACT FROM AUTHOR]

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,14C 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. [ABSTRACT FROM PUBLISHER]

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Abstract: The historical site of the Monte Mario lower Pleistocene succession (Rome, Italy) is an important marker of the Pliocene/Pleistocene boundary. Recently, the Monte Mario site was excavated and restudied. A spectacular angular unconformity characterizes the contact between the Monte Vaticano and the Monte Mario formations, which marks the Pliocene/Pleistocene boundary. Biostratigraphical analyses carried out on ostracod, foraminifer, and calcareous nannofossil assemblages indicate an Early Pliocene age (topmost Zanclean, 3.81–3.70 Ma) for the underlying Monte Vaticano Formation, whereas the Monte Mario Formation has been dated as early Pleistocene (Santernian, 1.66–1.59 Ma). Palaeomagnetic analyses point to C2Ar and C1r2r polarity chrons for the Monte Vaticano and the Monte Mario formations, respectively. The Monte Mario Formation consists of two obliquity-forced depositional sequences (MM1 and MM2) characterized by transgressive systems tracts of littoral marine environments at depths, respectively, of 40–80 m and 15–20 m. The data obtained from foraminifer and ostracod assemblages allow us to reconstruct early Pleistocene relative sea-level changes near Rome. At the Plio/Pleistocene transition, a relative sea-level drop of at least 260 m occurred, as a result of both tectonic uplift of the central Tyrrhenian margin and glacio-eustatic changes linked to early Pleistocene glaciation (Marine Isotope Stage 58). [Copyright &y& Elsevier]

Abstract: In this paper the ostracod assemblages recovered from several brackish Late Miocene Italian deposits have been analysed from a palaeobiogeographical perspective. During late Tortonian-early Messinian it is possible to recognize in Italy rich ostracod assemblages characterized by a wide contingent of taxa with central European or Mediterranean affinity, while only few brackish and freshwater ostracods show Paratethyan affinity. The recognized composition of the ostracod assemblages matches the palaeogeographic setting of the palaeo-Mediterranean/Paratethys at that moment. In fact during late Tortonian-early Messinian the palaeo-Mediterranean and Paratethysian domains were divided and, even if the connection via the present Marmara Sea-Strimon Basin was still open, the different salinity between them represented an ecological barrier, preventing faunal exchanges. Since normal aquatic migration was impossible, it must be assumed that the Paratethyan-like taxa entered the palaeo-Mediterranean area via passive dispersal by aquatic birds. On the contrary, the ostracod assemblages from the Italian Lago-Mare deposits show the absolute predominance of Paratethyan taxa, which, according to the known palaeogeographic setting during the late Messinian Lago-Mare event, could actively migrate from the Paratethys domain, colonizing the palaeo-Mediterranean, whose endemic fauna was severely impoverished by the Messinian salinity crisis and the following water dilution. [Copyright &y& Elsevier]

Seventeen layers characterized by soft-sediment deformation structures (SSDS) were identified within the "calcari di Fiumicello", an upper Messinian (Miocene) stratigraphic unit (30 m thick), cropping out in the northern sector of the Gargano Promontory (Apulia, southern Italy). Facies analysis was performed on the whole outcrop and detailed sedimentological investigations were carried out on the deformed beds, in order to interpret the deformation mechanism, the driving mechanism and the possible trigger agent. Deformed layers occur in some thin-bedded ooidal limestones, skeletal calcarenite, as well as in some pebble-size conglomerate, alternated with marls, deposited in a protected embayment or barrier-island-lagoon system, possibly characterized by high salinity, and tidal influx. SSDS can be classified as load- and slump/slide structures. The continuous exposures allow us to follow a single deformed layer along tens of meters, hence several types of lateral variations were observed that can be summarised as follows: (1) SSDS disappear within a few meters (with a decreasing pattern of their deformation or in an abrupt way); (2) deformed layers laterally change in thickness and morphology; and (3) a single deformed bed can laterally correspond to two deformed beds. Most of the soft sediment deformation features were identified as liquefaction and/or fluidization features related to seismic shocks (seismites). Seismites are often used as an indicator of seismic events, especially along small outcrops, trench excavation and core analysis. This study highlights the value of the sedimentological analysis for paleoseismic investigations, with the aim of improving criteria for identifying seismites in the sedimentary record, and their suitability as marker of seismic events. [ABSTRACT FROM AUTHOR]

Study of the tectonically active L'Aquila Basin offers new insights into both the creation of the extensional intermontane basins of the central Apennines of Italy and their tectono-sedimentary evolution through time. The combination of large mammal remains, ostracods, molluscs, Mousterian tools, and 14C dating allows better definition of the onset and stratigraphic evolution of the L'Aquila Basin. Interpretation of a seismic reflection profile and well-log data allow evaluation of the subsurface setting of this sedimentary basin and its tectono-sedimentary evolution. The occurrence of a wedge-shaped seismic unit at the base of the basin sedimentary succession defines the first phase of basin fill during a late Piacenzian-Gelasian synrift stage. Activity along the main fault of the extensional fault system responsible for the onset and subsequent development of the western sector of the L'Aquila Basin (L'Aquila-Scoppito subbasin) migrated from southwest to northeast, reaching the presently active Mount Pettino normal fault only in the late Pleistocene-Holocene. The onset of sedimentation in the L'Aquila Basin was synchronous with the onset in the Tiberino Basin, and so the idea that these extensional intermontane basins become progressively younger from the Tyrrhenian toward the Adriatic side of the central Apennines is rejected. In the northern and central Apennines, only two major syndepositional extensional domains can be recognized: a late Miocene rifting area, which includes all the late Miocene extensional basins in Tuscany, and a late Pliocene to earliest Pleistocene rifting area, which possibly includes all the intermontane basins from the Tiberino Basin to the Sulmona Basin. The different time gaps between compressional and extensional deformation at any given locality in the central Apennines could indicate a partial decoupling of processes responsible for the migration of shortening and extension toward the foreland. Diachroneity between the eastward migration of shortening in the foreland and extension in the inner part of the orogen supports the notion that the central Apennines were created as a result of a partially decoupled collision zone. Study of the onset of the central Apennine extensional intermontane basins, together with their seismic activity, indicates that the central Apennine postorogenic extensional domain represents an archive of ~3 m.y. of continued crustal extension. These findings help to refine models of the long-term extensional rate of the central Apennines, and they provide a basis for more reliable seismotectonic models for one of the most seismically active sectors of the central Mediterranean area. [ABSTRACT FROM AUTHOR]

Abstract: Late Miocene brackish ostracods and molluscs collected in three Italian basins show noticeable differences in their taxonomic composition, despite their capability of dispersing across wide geographic areas. In the Venetian-Friulian Basin (northern Italy), the upper Tortonian sediments contain oligotypic ostracod assemblages including Hemicyprideis dacica dacica, Hemicytheria pejinovicensis, and Loxoconcha cf. L. josephi and few gastropods referable to Planorbidae and Stenothyroides, which are typical of the central Paratethys. In central Italy, the brackish ostracods and molluscs recovered from upper Tortonian-lower Messinian deposits from four Tuscan basins (Volterra-Radicondoli, Velona, Baccinello-Cinigiano, and Valdelsa) display high affinity at a generic level but strong endemicity at a specific level. At Cessaniti (southern Italy), the upper Tortonian unit contains oligotypic brackish ostracods and molluscs: Mediocytherideis (Sylvestra) posterobursa, Cyprideis ruggierii, Loxoconcha cf. L. biformata, and Zonocypris membranae quadricella characterise the ostracod fauna, while Granulolabium bicinctum and Hydrobia frauenfeldi are the dominant molluscs. The recovered ostracods have a strong affinity with brackish species from central and eastern Palaeo-Mediterranean areas, whereas the molluscs present a Paratethyan origin. Despite the fact that the basins are all brackish and partly coeval, the systematics of these assemblages highlights the absence of common species among the three studied areas. Geochemical analyses (stable isotopes and trace elements) are performed on ostracods, and 87Sr/86Sr ratios are established in molluscs and echinoids. The results suggest brackish environments with different compositions and origins of solutes in the three different areas. The Tuscan basins are characterised by brackish waters, with NaCl-enriched waters coming from aquifers of Triassic evaporite bedrock. The brackish deposits of the Venetian-Friulian Basin and Cessaniti are true marginal marine environments, although the northern basin may have been influenced by both the Paratethyan Sava Basin and the northern portion of the Palaeo-Mediterranean water bodies. [Copyright &y& Elsevier]

Abstract: Two possible alternative interpretations of the claimed Zanclean age () of two historical lithostratigraphic units of the Northern Apennines, usually referred to as Late Messinian in age and recording the so called Lagomare final event of the Messinian salinity crisis (MSC), are here discussed. The wrong age attribution of the Colombacci and “tetto” Fms. is ruled out based on data from the Maccarone and other sections showing that the Colombacci-Argille Azzurre Fm. boundary is basin wide synchronous and coincident with the Miocene-Pliocene boundary as far as it has been formally defined in the Eraclea Minoa GSSP. Alternatively, the opportunity of emending the Zanclean GSSP to a stratigraphically lower horizon recording the first evidence of marine influences in the Mediterranean following the MSC peak, seems not suitable, as (1) the marine signature of uppermost Messinian deposits is weak and still controversial and (2) no significant bio- and magnetostratigraphic events, well chronologically defined and recognizable at a global scale appear to be available to such a purpose. [Copyright &y& Elsevier]

Abstract: The Mondragone 1 well, drilled in 1968 by Agip, for hydrocarbon exploration, cut across siliciclastic fine-to-coarse-grained upper Miocene–Quaternary deposits, for a total depth of 2002 m. Thirteen cores have been recovered from 495 down to 2002 m. This paper deals with both the results of the biostratigraphical analyses performed on a new sampling of the cores and the significance of the well stratigraphy in the context of the late Messinian Lago–Mare episode in central Mediterranean. The Lago–Mare biofacies has been characterised from 675 down to 2002 m by the ostracod assemblages that are made of species belonging to the Loxocorniculina djafarovi Zone, as defined by Carbonnel [Carbonnel, G., 1978. La zone a Loxoconcha djaffarovi Schneider (Ostracoda, Miocène supérieur) ou le Messinien de la Vallée du Rhône. Rev. Micropaleontol. 21, 106–118.] (e.g. L. djafarovi, Loxoconcha eichwaldi, Cyprideis anlavauxensis, Amnicythere palimpsesta, Zalanyiella venusta). Thus, the Lago–Mare deposits have a true thickness of about 938 m since the strata show a mean dip value of 45°. Similar thickness (530 m) has been measured in the pre-Pliocene sediments drilled at ODP Site 652, which can be correlated with Mondragone 1 by the occurrence of brackish-water forms. In both these areas syn-rift depositional processes have been suggested to explain the unusual thickness of the late Messinian sediments. Data from seismic lines have been used to reconstruct the geometry and the structural setting of the Garigliano Basin during the latest Messinian. Moreover, the analysis of the SP log integrated with the palaeoecological indications from the ostracod assemblages allows us to suggest a possible sequence stratigraphy evolution of the Garigliano Basin during the late Messinian Lago–Mare episode. Different tectonic behaviour with differences in subsidence rates between the northern and the southern Tyrrhenian Basin have been suggested since the uppermost Messinian syn-rift clastic wedges recognized in the onshore of northern Latium and Tuscany show thickness lower than that drilled at the ODP Site 652 and at the Mondragone 1 well. [Copyright &y& Elsevier]