3,102 research outputs found
Very high resolution seismic surveys in the lagoon and gulf of Venice shallow waters
No full textWithin the framework of the geological mapping of the Venice area (CARG Project: Map Sheet 128 “Venezia” and Map Sheet 148-149 “Chioggia-Malamocco”) a very high resolution seismic survey (VHRS) was carried out to correlate data from hundreds of cores with the main aim to map the depth of the Late Pleistocene and Holocene unconformity (Brancolini et al., 2005; Rizzetto et al., 2005; Tosi et al., 2006a,b). Due to logistic and technical limits, the acquisition of seismic survey in the Venice Lagoon was restricted to the channels with more of 5 m water depth, most of them artificial or dredged. A new survey, with the aim to extend the VHRS surveys to the shallow water, such as the tidal flats, is in progress within the Co.Ri.La. Project framework (3.16 Subproject). The Co.Ri.La 3.16 Subproject is based on an acquisition system installed on a boat with a very shallow draught. The new survey will allow the detection and mapping of many interesting geological-geomorphologic structures, i.e. paleoriver beds, ancient lagoon channels and shoreline ridges, that are like-outcropping, and that have been only partially recognized in the previous surveys.PublishedBarcelona (Spain)7A. Geofisica di esplorazioneope
Very high resolution seismic surveys in the lagoon and gulf of Venice shallow waters
No full textWithin the framework of the geological mapping of the Venice area (CARG Project: Map Sheet 128 “Venezia” and Map Sheet 148-149 “Chioggia-Malamocco”) a very high resolution seismic survey (VHRS) was carried out to correlate data from hundreds of cores with the main aim to map the depth of the Late Pleistocene and Holocene unconformity (Brancolini et al., 2005; Rizzetto et al., 2005; Tosi et al., 2006a,b). Due to logistic and technical limits, the acquisition of seismic survey in the Venice Lagoon was restricted to the channels with more of 5 m water depth, most of them artificial or dredged. A new survey, with the aim to extend the VHRS surveys to the shallow water, such as the tidal flats, is in progress within the Co.Ri.La. Project framework (3.16 Subproject). The Co.Ri.La 3.16 Subproject is based on an acquisition system installed on a boat with a very shallow draught. The new survey will allow the detection and mapping of many interesting geological-geomorphologic structures, i.e. paleoriver beds, ancient lagoon channels and shoreline ridges, that are like-outcropping, and that have been only partially recognized in the previous surveys.PublishedBarcelona (Spain)7A. Geofisica di esplorazioneope
CONTRIBUTION OF SEISMIC PROFILES, HISTORICAL MAPS, AND DIGITAL ELEVATION MODEL TO DEFINE BURIED GEOMORPHOLOGICAL FEATURES IN THE VENICE LAGOON SUBSOIL (ITALY)
No full textRecently, the integrated analysis of Very High Resolution Seismic (VHRS) profiles, satellite images, aerial photographs, maps, and topographic/bathymetric data has given an important contribution to the identification of buried geomorphological features in the Venice lagoon subsoil down to about 30 m b.s.l.. Investigations allow to attribute these features to the Late Pleistocene and the Holocene and to point out their relation with the evolution of the lagoon basin.
Results of this study are also assuming great importance in relation to coastal environmental problems. Relict sandy geomorphological features, characterized by high permeability, act as preferred pathways for groundwater flow and solute transport, enhancing saltwater intrusion in the watershed (Carbognin & Tosi, 2003; Carbognin et al., 2005; Pousa et al., 2007). Furthermore, salinization process can also trigger land subsidence induced by clayey particles rearrangement (Meade, 1964).
In addition, the different kinds of deposits that characterize geomorphological features are responsible for a differential lowering of the territory (Teatini et al., 2005).
Aerial photograph and satellite image interpretations, analysis of historical and recent maps, field surveys, and topographic/bathymetric investigations were first used to identify the main buried and surface geomorphological features. Afterwards, an important contribution to the present study was given by a single channel VHR seismic system, optimized for surveys in shallow water less than 1 m depth (Brancolini et al., 2006; Brancolini et al., 2007).
Seismic profiles were calibrated and validated using geological information obtained from existing cores.
The detailed reconstruction of the seismic-morpho-stratigraphic units present in the subsoil of the Venice Lagoon is still in progress. It is obtained integrating results of the investigations previously described with sedimentological, stratigraphic, geotechnical, mineralogical, textural, and paleoenvironmental data, and 14C dating (Serandrei Barbero et al., 2006; Tosi et al., 2007a; Tosi et al., 2007b).
The combined interpretation of results obtained from remote sensing investigations, topographic/bathymetric measurements, VHRS surveys, and analysis of multidisciplinary geological data allowed the discovery and characterization of buried paleoriver beds, ancient tidal channels, and paleobeach ridges and pointed out the relation among geomorphological features occurring in the lagoon basin and in the watershed.
In fact, most of the features recognized in the mainland, which apparently come to an end in correspondence to the lagoon margin, continue into the lagoon basin, where their identification is made difficult by the presence of water and by depositional/erosive processes active in this kind of environment.
Data show that relict geomorphological features composed of high permeability deposits provide the hydraulic connection between freshwater aquifers and the sea. In particular, results of the present study point out that well developed paleoriver systems, intersecting the southern lagoon margin and the nearby coastline and characterized by permeable sediments, represent preferential way of communication among waters having different salinity. By contrast thick silty-clayey layers preclude the salty pollution in the aquifers from the lagoon and the sea.
As pointed out close to the lagoon margin (Rizzetto et al., 2003), the different kinds of deposits, related to the presence of distinct geomorphological features, contribute to the differential lowering of the lagoon basin (Teatini et al., 2005). In particular, organic soils correspond to highly sinking areas, whereas sandy-silty sediments, which constitute fluvial and beach ridges, are more stable.
Future investigations have to be addressed to the quantitative geomorphological analysis aimed to know the past hydrologic conditions of the drainage systems, and to analyze the formative processes that control the morphological setting and evolution of lowland fluvial river and tidal creek systems.PublishedMunich, Germany6A. Monitoraggio ambientale, sicurezza e territorioope
CONTRIBUTION OF SEISMIC PROFILES, HISTORICAL MAPS, AND DIGITAL ELEVATION MODEL TO DEFINE BURIED GEOMORPHOLOGICAL FEATURES IN THE VENICE LAGOON SUBSOIL (ITALY)
No full textRecently, the integrated analysis of Very High Resolution Seismic (VHRS) profiles, satellite images, aerial photographs, maps, and topographic/bathymetric data has given an important contribution to the identification of buried geomorphological features in the Venice lagoon subsoil down to about 30 m b.s.l.. Investigations allow to attribute these features to the Late Pleistocene and the Holocene and to point out their relation with the evolution of the lagoon basin.
Results of this study are also assuming great importance in relation to coastal environmental problems. Relict sandy geomorphological features, characterized by high permeability, act as preferred pathways for groundwater flow and solute transport, enhancing saltwater intrusion in the watershed (Carbognin & Tosi, 2003; Carbognin et al., 2005; Pousa et al., 2007). Furthermore, salinization process can also trigger land subsidence induced by clayey particles rearrangement (Meade, 1964).
In addition, the different kinds of deposits that characterize geomorphological features are responsible for a differential lowering of the territory (Teatini et al., 2005).
Aerial photograph and satellite image interpretations, analysis of historical and recent maps, field surveys, and topographic/bathymetric investigations were first used to identify the main buried and surface geomorphological features. Afterwards, an important contribution to the present study was given by a single channel VHR seismic system, optimized for surveys in shallow water less than 1 m depth (Brancolini et al., 2006; Brancolini et al., 2007).
Seismic profiles were calibrated and validated using geological information obtained from existing cores.
The detailed reconstruction of the seismic-morpho-stratigraphic units present in the subsoil of the Venice Lagoon is still in progress. It is obtained integrating results of the investigations previously described with sedimentological, stratigraphic, geotechnical, mineralogical, textural, and paleoenvironmental data, and 14C dating (Serandrei Barbero et al., 2006; Tosi et al., 2007a; Tosi et al., 2007b).
The combined interpretation of results obtained from remote sensing investigations, topographic/bathymetric measurements, VHRS surveys, and analysis of multidisciplinary geological data allowed the discovery and characterization of buried paleoriver beds, ancient tidal channels, and paleobeach ridges and pointed out the relation among geomorphological features occurring in the lagoon basin and in the watershed.
In fact, most of the features recognized in the mainland, which apparently come to an end in correspondence to the lagoon margin, continue into the lagoon basin, where their identification is made difficult by the presence of water and by depositional/erosive processes active in this kind of environment.
Data show that relict geomorphological features composed of high permeability deposits provide the hydraulic connection between freshwater aquifers and the sea. In particular, results of the present study point out that well developed paleoriver systems, intersecting the southern lagoon margin and the nearby coastline and characterized by permeable sediments, represent preferential way of communication among waters having different salinity. By contrast thick silty-clayey layers preclude the salty pollution in the aquifers from the lagoon and the sea.
As pointed out close to the lagoon margin (Rizzetto et al., 2003), the different kinds of deposits, related to the presence of distinct geomorphological features, contribute to the differential lowering of the lagoon basin (Teatini et al., 2005). In particular, organic soils correspond to highly sinking areas, whereas sandy-silty sediments, which constitute fluvial and beach ridges, are more stable.
Future investigations have to be addressed to the quantitative geomorphological analysis aimed to know the past hydrologic conditions of the drainage systems, and to analyze the formative processes that control the morphological setting and evolution of lowland fluvial river and tidal creek systems.PublishedMunich, Germany6A. Monitoraggio ambientale, sicurezza e territorioope
Sicurezza e compatibilità geometrica della via dei tram-treno in ferrovia // Safety and geometric compatibility of the track of the tram-train in railroads
No full textUna possibile risposta alla crescente domanda di mobilità nelle aree urbane e suburbane è costituita dall’interoperabilità del trasporto pubblico locale, in particolare del trasporto a guida vincolata che, per sua natura, consente capacità di trasporto elevate e basso impatto ambientale grazie all’utilizzo di veicoli a trazione elettrica. Un tipico esempio di sistema trasporto pubblico interoperabile a guida vincolata è il così detto “tram-treno”, che realizza l’integrazione fra tranvia e ferrovia, mediante veicoli tranviari opportunamente modificati, come i tram della città tedesca di Karlsruhe, o appositamente progettati, come i veicoli RegioCitadis di Kassel, per poter circolare su entrambi i tipi di infrastruttura. In tal modo diviene possibile collegare direttamente, senza cambi della modalità di trasporto e senza investire nella realizzazione di nuove infrastrutture, il centro cittadino con l’hinterland, sfruttando la rete tranviaria cittadina e le linee ferroviarie suburbane, spesso caratterizzate da una bassa densità di traffico o, in taluni casi, addirittura dismesse. Un veicolo per poter circolare indifferentemente su tranvia e su ferrovia deve però soddisfare sia alle diverse regole di esercizio sia ai differenti requisiti imposti dai due tipi d’infrastruttura, fra i quali di fondamentale importanza risultano quelli legati alla sicurezza ed alla geometria della via. Prendendo come caso di studio la città di Roma, il presente lavoro ha inteso fornire un quadro esauriente di tutti i possibili ostacoli di natura tecnica che debbono essere superati per consentire ad un veicolo di derivazione tranviaria l’utilizzazione dell’infrastruttura ferroviaria, individuando, per ciascuno di essi, delle possibili soluzioni. In particolare, è stato elaborato lo schema di principio di un dispositivo per scartamento variabile per veicoli tranviari a pianale integralmente ribassato (carrelli a ruote indipendenti). Si è analizzato un profilo speciale di ruota per veicoli “tram-treno”, studiandone l’interazione geometrica (accoppiamento di forma) con le rotaie ferroviarie e l’influenza sul comportamento della dinamica di marcia, in piena curva, di un veicolo tranviario in ferrovia, in confronto con un profilo di ruota ferroviario standard. Infine, un possibile sviluppo dello studio consiste nell’analisi del comportamento dinamico del profilo di ruota “tram-treno” in corrispondenza dei punti singolari della via, in particolar modo dei deviatoi ferroviari, nell’affrontare i quali tale profilo, vista l’esiguità del bordino, potrebbe presentare notevoli differenze rispetto al profilo di una ruota ferroviaria. Si è quindi condotto uno studio preliminare e qualitativo del passaggio di una ruota “tram-treno” in corrispondenza delle sezioni caratteristiche di un deviatoio ferroviario, che ha permesso di individuare le sezioni critiche su cui concentrare le successive simulazioni
Sicurezza e compatibilità geometrica della via nei sistemi di trasporto urbani e suburbani
No full textAtti del XIII Seminario Scientifico SIDT, Pisa, 14 ottobre 200
Reduction Potential of Gaseous Emissions in European Ports Using Cold Ironing
No full textProviding electrical power to ships while they are docked, cold ironing allows ships to turn off their engines and reduces emissions of air pollutants and greenhouse gases. This study identifies and assesses ship and port emissions and analyzes the potential for emission reduction achievable by cold ironing in European ports. It includes (1) a review of the current state of cold ironing in European ports; (2) an analysis of the time spent in ports by ships; (3) a quantification of emissions potentially avoided by means of a larger-scale use of cold ironing in Europe; (4) an estimation of the benefits achievable and the perspective to play a role in meeting emission reduction targets, improving air quality in port cities; (5) an analysis of the challenges and limitations of larger-scale cold ironing implementation; (6) potential solutions to overcome them. The results of this study could have important implications for (a) the shipping industry, which could benefit from the need for additional standardized electrical equipment onboard; (b) port authorities, which could benefit from providing additional services to the ships; (c) policymakers working to reduce emissions and promote energy efficiency, who could better approach their local and global targets
- …
