14 research outputs found

    Benthic foraminifers and gastropods from the Gratteri Formation cropping out near Isnello (Madonie Mts., Sicily)

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    Nine samples were collected from a 3 m thick section of the Gratteri Formation cropping out at Casa Asciutto, near Isnello (Madonie Mts.) consisting of yellow silty marls alternating to bioclastic marly and quartzy sandstones, rich in displaced larger foraminifers such as lepidocyclinids (Nephrolepidina and Eulepidina), and nummulitids (Heterostegina and Operculina). Planktonic foraminifers are badly preserved or absent through the section because of dissolution. The pre - sence of displaced specimens of Nephrolepidina praemarginata, which was the object of a biometrical analysis for the embryonic apparatus, dates the studied section at least late Rupelian. In the silty marl layers deep water agglutinated foraminifers (DWAF) and bathyal hyaline foraminifers are frequent; 36 agglutinated and 26 hyaline species of benthic foraminifers, some of which in open nomenclature, were identified. Upsection the specific diversity tends to decrease, whereas the quartz supply increases and assemblages become exclusively constituted by agglutinated DWAF with predominant tubular suspension feeding taxa. In three samples few, badly preserved and displaced gastropods belonging to Architectonicidae, Ampullinidae, Trochidae, Cerithiopsidae, Rissoidae and Pyramidellidae were recognized. The Gratteri Formation deposited during the late Rupelian in a basin periodically affected by gravitative and turbiditic flows, which carried basinward coeval shallow-water larger foraminifers and gastropods. The dissolution of the most calcareous taxa is imputed to the fluctuations and local rise of the calcite compensation depth (CCD) or, more likely, to reducing conditions in bottom sediments

    Land mollusc palaeocommunity dynamics related to palaeoclimatic changes in the Upper Pleistocene alluvial deposits of Marche Apennines (central Italy).

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    A detailed chronological scheme based on 14C and U/Th datings of Upper Pleistocene slope and alluvial deposits in the Upper Esino River Basin (Marche, central Italy), containing archaeological remains, pollens and land molluscs, constrains the time-range deposition of cold climate slope-waste and coeval alluvial deposits between the Middle Pleniglacial and Late Glacial. Integrating molluscan analyses and stratigraphical data (sedimentary features, 14C and U/Th datings) from an Upper Pleistocene stratigraphical section of fluvial gravelly and sandy-silty sediments near Matelica (Macerata) allowed a detailed palaeoenvironmental reconstruction. Well preserved land gastropod assemblages from nine levels, typical of cold/cool climate and variable humidity of stadials and interstadials showing prevalence of open and dry environment, were analysed by quantitative methods. Palaeocommunity dynamics through the section, due to alternate cool-cold climatic conditions, proved to be consistent with sedimentary features: braid plain channel gravelly sediments of stadials yielded poor-species assemblages of very dry exposed places (steppe-like), sandy-silty sediments of interstadials recorded diversified molluscan fauna with steppe-prairie species and taxa of more or less damp conditions, suggesting more humid environment. Dominance or decrease in specimen number of one species and variation in species composition were strongly influenced by palaeoclimatic changes, highlighting detailed climatic and palaeoenvironmental variations through time

    Evolution of the Sele River coastal plain (southern Italy) during the Late Quaternary by inland and offshore stratigraphical analyses

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    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

    Earthquake and Tsunami Workflow Leveraging the Modern HPC/Cloud Environment in the LEXIS Project

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    Accurate and rapid earthquake loss assessments and tsunami early warnings are critical in modern society to allow for appropriate and timely emergency response decisions. In the LEXIS project, we seek to enhance the workflow of rapid loss assessments and emergency decision support systems by leveraging an orchestrated heterogeneous environment combining high-performance computing resources and Cloud infrastructure. The workflow consists of three main applications: firstly, after an earthquake occurs, its shaking distribution (ShakeMap) is computed based on the OpenQuake code. Secondly, if a tsunami may have been triggered by the earthquake, tsunami simulations (first a fast and coarse and later a high-resolution and computationally intensive analysis) are performed based on the TsunAWI simulation code that allows for an early warning in potentially affected areas. Finally, based on the previous results, a loss assessment based on a dynamic exposure model using open data such as OpenStreetMap is performed. To consolidate the workflow and ensure respect of the time constraints, we are developing an extension of a time-constrained dataflow model of computation, layered above and below the workflow management tools of both the high-performance computing resources and the Cloud infrastructure. This model of computation is also used to express tasks in the workflow at the right granularity to benefit from the data management optimisation facilities of the LEXIS project. This paper describes the workflow, the associated computations and the model of computation within the LEXIS platform

    Middle-to late-Holocene environmental changes in the Garigliano delta plain (Central Italy): which landscape witnessed the development of the Minturnae Roman colony?

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    Geomorphologic, stratigraphic, faunistic, palynological and 14C analyses were carried out in the area of the mouth of the Garigliano River characterized by two strand plains that are referred to the Eutyrrhenian and the Holocene, rimming two depressed zones separated by the Garigliano River channel. This study depicts the palaeoenvironmental evolution over the last 8200 years and the landscape context at the time of Minturnae Roman colony. Between 8200 and 7500 yr BP, a wet zone occurred in the northern zone, whereas in the southern part, a lagoon developed. During the final transgression stage and the beginning of the sea level still stand (7500–5500 yr BP), a freshwater marsh formed in the northern zone, and the width of the southern lagoon decreased. Between 5500 and 3000 yr BP, the coastal barrier changed into a delta cusp, a freshwater marsh also appeared in the southern part and the river wandered between the twin marshes. Because of local uplift, previously unknown in this area, part of the floor of the southern marsh emerged, and after 4000 yr BP, both marshes became coastal ponds with prevailing clastic sedimentation. A progressive increment in anthropic forcing on the land took place after 3000 yr BP. The Marica sanctuary was built (7th century BC), and the Roman colony of Minturnae was developed beginning the 3rd century BC. The shallow depth of the ponds prevented their use as harbours, and saltwork plants can be ruled out based on the faunal and palynological data. The ongoing infilling of both ponds was never completed, and their reclamation is still in progress

    Middle-to late-Holocene environmental changes in the Garigliano delta plain (Central Italy). Which landscape witnessed the development of the Minturnae Roman colony?

    No full text
    Geomorphologic, stratigraphic, faunistic, palynological and 14C analyses were carried out in the area of the mouth of the Garigliano River characterized by two strand plains that are referred to the Eutyrrhenian and the Holocene, rimming two depressed zones separated by the Garigliano River channel. This study depicts the palaeoenvironmental evolution over the last 8200 years and the landscape context at the time of Minturnae Roman colony. Between 8200 and 7500 yr BP, a wet zone occurred in the northern zone, whereas in the southern part, a lagoon developed. During the final transgression stage and the beginning of the sea level still stand (7500–5500 yr BP), a freshwater marsh formed in the northern zone, and the width of the southern lagoon decreased. Between 5500 and 3000 yr BP, the coastal barrier changed into a delta cusp, a freshwater marsh also appeared in the southern part and the river wandered between the twin marshes. Because of local uplift, previously unknown in this area, part of the floor of the southern marsh emerged, and after 4000 yr BP, both marshes became coastal ponds with prevailing clastic sedimentation. A progressive increment in anthropic forcing on the land took place after 3000 yr BP. The Marica sanctuary was built (7th century BC), and the Roman colony of Minturnae was developed beginning the 3rd century BC. The shallow depth of the ponds prevented their use as harbours, and saltwork plants can be ruled out based on the faunal and palynological data. The ongoing infilling of both ponds was never completed, and their reclamation is still in progress
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