Search results for "Submarine"

Integration of onshore and offshore seismic arrays to study the seismicity of the Calabrian Region: a two steps automatic procedure for the identific…

2014

Abstract. We plan to deploy in the Taranto Gulf some Ocean Bottom broadband Seismometer with Hydrophones. Our aim is to investigate the offshore seismicity of the Sibari Gulf. The seismographic network optimization consists in the identification of the optimal sites for the installation of the offshore stations, which is a crucial factor for the success of the monitoring campaign. In this paper, we propose a two steps automatic procedure for the identification of the best stations geometry. In the first step, based on the application of a set of a priori criteria, the suitable sites to host the ocean bottom seismic stations are identified. In the second step, the network improvement is eval…

The INGV's new OBS/H: Analysis of the signals recorded at the Marsili submarine volcano

2009

Abstract The ocean bottom seismometer with hydrophone deployed on the flat top of the Marsili submarine volcano (790 m deep) by the Gibilmanna OBS Lab (CNT–INGV) from 12th to 21st July, 2006, recorded more than 1000 transient seismic signals. Nineteen of these signals were associated with tectonic earthquakes: 1 teleseismic, 8 regional (located by INGV) and 10 small local seismic events (non located earthquakes). The regional events were used to determine sensor orientation. By comparing the signals recorded with typical volcanic seismic activity, we were able to group all the other signals into three categories: 817 volcano–tectonic type B (VT-B) events, 159 occurrences of high frequency t…

Analysis and assessment of trace element contamination in offshore sediments of the Augusta Bay (SE Sicily): A multivariate statistical approach base…

2014

Abstract An application of multivariate statistical methods is provided to identify anthropogenic contaminants and lithogenic elements in offshore sediments collected near the heavily industrialized Augusta Bay, Sicily. An exploratory statistical technique, based on canonical correlation analysis (CCA) and mixture density estimation approach, is used for distinguishing between natural and anthropogenic contributions of trace elements in the investigated sediments. Following the intensive industrialization of Augusta area, marine sediments reveal the severe impact of local anthropogenic activities for many elements (e.g. As, Cd, Hg, Pb, and Sb), which are considered very dangerous for the en…

NEOTECTONIC ACTIVITY AND EMISSION OF FLUIDS IN THE NORTHWEST SICILY CHANNEL

The southern Sicilian coast represents an important contribution to Italian tourism, the Sicily Channel is an important communication path because at the top of its seafloor there are many pipelines, and submarine communication cables which are laid to carry signals, and which are very important to the minor islands. In this work, we are presenting results of the detailed geomorphological and seismostratigraphic analysis based on new very high-resolution dataset (multibeam and CHIRP) acquired during the ACUSCAL 2015 Cruise. We also used low resolution bathymetric and seismic data provided from online database (ViDEPI, GEBCO, EMODnet). This study allows us to reconstruct the tectonic volcani…

PROCESSI ATTIVI NEL MARGINE CONTINENTALE DELLA SICILIA NORD-OCCIDENTALE: NEOTETTONICA, RISALITA DI FLUIDI E FENOMENI GRAVITATIVI

2014

La ricerca riguarda l’analisi degli elementi morfostrutturali, le strutture legate alle emissioni di fluidi ed i fenomeni di trasporto sia gravitativo che selettivo, in ambiente sommerso ed emerso, presenti nel settore del margine continentale nord-siciliano compreso tra i meridiani passanti per le isole Egadi e Cefalù, al fine di ottenere un modello evolutivo durante il Quaternario. In particolare sono stati studiati in dettaglio: a) gli elementi morfostrutturali, al fine di ottenere informazioni sull’evoluzione recente dell’area, concentrando l’attenzione sulle faglie recenti e attive, integrando anche le informazioni concernenti la sismicità dell’area, ricavati dai database online; b) le…

Submarine canyons of north-western Sicily(Southern Tyrrhenian Sea): Variability in morphology, sedimentary processes and evolution on a tectonically …

2014

Bathy-morphological analysis of submarine canyons across the north-western Sicily continental slope

2016

We present here the results of the morpho-bathymetric analyses of the main submarine canyons along the upper slope off the north-western Sicily. This region developed during the Neogene as the transition area between the Sicilian fold and thrust belt and the Tyrrhenian basin realm. Along the upper slope, a dense network of submarine canyon develops from 80 m water depth up to more than 2000 m, showing a large variability of sizes and morphology. In this area submarine canyons play a crucial role related to the along-slope sedimentary transport and are among the most distinctive features of the submarine seascape. This study is based on a quantitative analysis of a high resolution multibeam …

Eustatic and oceanographic control on sedimentary evolution of middle-late Quaternary shelf margin-to-upper slope deposits on the Egadi Islands offsh…

2016

During the past decades a number of sequence stratigraphy studies illustrated how, during Quaternary, interaction between sea level changes and sediment supply controlled the depositional evolution along continental margins, giving a cyclic signature to the sedimentary infilling. However, as both deposition and erosion are processes ultimately controlled by balance between environmental energy and sedimentary influx, also the oceanographic regime takes part in controlling the sedimentary growth along the continental margin. This is exactly what occurs on physiographic settings as islands offshore areas, where bottom currents can be very energetic. In the western Sicily offshore, southwards …

Development, human impact and habitat distribution in submarine canyons of the Central and Western Mediterranean

2015

We present in this paper different studies on canyon systems, adopting distinct approaches, temporal and spatial scales. Most of our study areas coincide with the NW Sicilian canyons, which present striking differences in their morphologies in response to the Plio-Quaternary tectonic evolution of the northern Sicilian margin. In the present-day, active sedimentary processes inferred from bedform analyses along some of the studied canyons could drive to enhanced biological activities along them. This is also confirmed by an on-going study of the impact of trawling fishery on the morphology and sedimentary environments of the Sicilian margin, where intense deep-sea bottom trawling activities …

Computation of run-up heights for landslide-generated tsunami. An attempt of hazard assessment in the North Sicily continental margin

2014

The North Sicily continental margin is a very active region located in a transitional area between the Sicilian- Maghrebian Chain to the south and the southern Tyrrhenian Sea to the north. Strong seismicity, active tectonics and volcanism, fluid escape, high sediment supply and widespread mass movements exposed this region to marine geohazards, with a potential for tsunami generation (e.g. Messina 1908, Stromboli 2004 events). In recent years, high resolution swath mapping and high resolution to high penetration seismic reflection profiles have been collected during several oceanographic cruises, in the frame of the MaGIC and CARG projects. Morphobatymetric and geoseismic analysis evidenced…