Search results for "grafica"
showing 10 items of 553 documents
Triassic/Jurassic boundary in peritidal carbonates from western Tethys
2016
A carbonate platform from the western margin of the Ionian Tethys has been investigated for biotic and geochemical variations across the Triassic/Jurassic boundary (TJB). The section of Mount Sparagio (north-western Sicily) exposes a peritidal succession of Rhaetian-Hettangian age with a thickness of about 400 m. The peritidal sediments are organized in metre-scale shallowing upward cycles formed by subtidal, intertidal and supratidal facies. Along the section, the subtidal facies vary from bioturbated mud/wackestones with rare mollusc shells, to Megalodont-rich wacke/packstones to, more rarely, coral bafflestones, most likely as response to variations of the accommodation space and water e…
Benthic foraminifera as indicators of relative sea-level fluctuations: Paleoenvironmental and paleoclimatic reconstruction of a Holocene marine succe…
2017
This study presents the results of an integrated stratigraphic analysis conducted on a marine gravity core (MSK-12 C4) recovered from the outer continental shelf (82 mwater depth) of western Calabria, ~2.6 km, NE of Capo Vaticano (Eastern Tyrrhenian margin). The gravity core MSK-12 C4 recovered a stratigraphic succession of 4.18 m beneath the seafloor representing the last ~11.1 ka. Sedimentological analysis, micropaleontological quantitative analysis on benthic foraminiferal assemblages, tephrostratigraphy, sequence stratigraphic analysis of high resolution reflection seismic data recorded in the core site area and AMS 14C absolute age determinations allowed reconstructing the marine recor…
Sea-level changes during the last 41,000 years in the outer shelf of the southern Tyrrhenian Sea: Evidence from benthic foraminifera and seismostrati…
2011
Abstract An integrated high resolution study based both on a seismostratigraphic approach and on a sedimentary core (VIB 10), collected in the outer shelf (127 m depth) from the southern Tyrrhenian Sea (Gulf of Termini, Sicily), provides new data about climatic, eustatic and paleoenvironmental changes during the last ∼41,000 years. The results based on the interpretation of a seismic profile, on benthic foraminifera assemblages and on δ18O records, allowed recognition of two drastic sea-level falls during the Last Glacial Maximum (LGM) and the Younger Dryas (YD). The short deglacial event, between LGM and YD, known as Bolling/Allerod, played an important role in the sea-level rise that prod…
Growth and geomorphic evolution of the Ustica volcanic complex at the Africa-Europe plate margin (Tyrrhenian Sea)
2021
18 pages, 13 figures, 1 table
Magmatism Along Lateral Slab Edges: Insights From the Diamante-Enotrio-Ovidio Volcanic-Intrusive Complex (Southern Tyrrhenian Sea)
2019
Volcanic‐intrusive complexes often formed along lateral slab edges as a consequence of subduction‐induced mantle flow. We investigate this process in the southern Tyrrhenian Sea by integrating multibeam bathymetry, seismic‐reflection data, regional magnetic anomalies data, and seismological data. The interpretation of the data highlights the presence of magmatic intrusions that locally reach the seafloor forming volcanic edifices. Chimneys, lava flows, and laccoliths are observed beneath and surrounding the volcanoes. The emplacement and cooling of the magma occurred during the Brunhes Chron. The volcanoes are not active even if the hydrothermal activity occurs. The volcanic‐intrusive compl…
Le unità fisiografiche Paesaggistiche Costiere
2008
A facies distribution model controlled by a tectonically inherited sea bottom topography in the carbonate rimmed shelf of the Upper Tithonian–Valangi…
2016
The Upper Tithonian–Valanginian shallow-water carbonates outcropping in the Palermo Mts (NW Sicily) consist of several facies associations reflecting different depositional environments of a carbonate rimmed shelf, pertaining to the Southern Tethyan continental margin. The reconstructed depositional model, based on the sedimentological features, cyclic facies arrangement and biota distribution, shows that a wide protected lagoon, dominated by algae, molluscs and scattered patch reefs, was bordered landward by a tidal flat, where stromatolitic algal mats were cyclically subaerial exposed, and seaward by a marine sand belt and reef complex. Oolitic packstone-grainstone lithofacies, cyclically…
The geographic information in the assessment of geohazard in the marine environment
2011
Slope instability and erosion, mass transport, volcanic and tectonic activity, fast sediment accumulation fluid escape are the main processes responsible for the geohazard in marine environment. A major knowledge about the geological setting of the offshore areas and related processes can be crucial to assess and manage the potential geological risks. High resolution morphobathymetric surveys, yielded in the frame of the MaGIC project (Marine Geohazards along the Italian Coasts), integrated with previously acquired data, single-channel seismic reflection profiles, backscatter data and sediments sampling, allow to define the geomorphological, stratigraphic and structural features in the offs…
Deep controls on Foreland Basin System evolution along the Sicily Thrust Belt
2014
The palinspastic restoration of the Sicilian crustal geological cross section (Catalano et al., 2013) points out two subsequent main thrust (MT1 and MT2) active during the Neogene tectonic evolution as well as the decrease of slip and shortening rate estimated for MT2 with respect to MT1 early main thrust. During orogenic building, syn-tectonic deposits are accumulated inside wedge-top-basin that grow on top of thrust sheets. Sedimentary and stratigraphic features of wedge-top basin change trough time following fold and thrust belt evolution. Neogene-Quaternary syn- tectonic successions (terrigenous, evaporitic, hemipelagic and shallow water deposits) extensively crop-out, in more or less w…
La spettroscopia ad ablazione laser per analisi stratigrafiche: esempi di applicazioni per lo studio dei beni culturali
2011
La spettroscopia ad ablazione laser (LIBS), a differenza di altre tecniche d'indagine, permette di condurre analisi stratigrafiche anche direttamente sul campione tramite impulsi consecutivi sullo stesso punto. Le attività condotte hanno riguardato l'ottimizzazione dei parametri strumentali (laser energy, delay, exposition time) per verificare la possibilità di ottenere profili di profondità degli elementi chimici costituenti materiali di differente tipologia (bronzi archeologici, lapidei, materiali pittorici, etc.), valutando anche l'influenza delle variabili presenti (spessori, composizione, proprietà del plasma). Tale approccio metodologico, seppur micro-distruttivo, evita la necessità d…