GNGTS 2014 - Atti del 33° Convegno Nazionale

active, they still offset the sediments till very recent time (a precise seismic stratigraphy of the area is not available) and must be reconsidered in the seismo-tectonic assessment of the eastern Tyrrhenian margin. In brief, during the MarBeep 2014 multichannel seismic investigations and detection of the acoustic backscatter of the water column by multibeam systems were carried out together. The results of these surveys allowed to define the depths of the free gas zones and to map their extention field. Further analyses, including seismic amplitude, will be necessary to precisely locate the seeps and define their exact geometry and to tie them to their deepest source, which indeed look to be the Messinian evaporites, as previously suggested. Acknowledgements. We warmly thank the crew of the R/V Urania and the scientific party on board the MarBeep 2014 campaign for their contribution to the success of the cruise. More information about the cruise are available in the report upon request from the corresponding author. This research was funded by the Ritmare Project (www.ritmare. it). ���������� ������ ������ ������� ������� �������� ����� ������ ���������� ����������� ������ ���������� ����� Scientific party: Marzia Rovere, Fabiano Gamberi, Elisa Leidi, Alessandra Mercorella, Andrea Gallerani, Fabio Savelli, Fabrizio Zgur, Lorenzo Sormani, Lorenzo Facchin, Gianpaolo Visnovic, Bruna Petani, Eugenio Rastelli, Andrea Fioretti, Heba Rashed, Luciano Giannini, Yuri Galletti, Fabio Canziani, Filippo Villi. References Boetius A.; 2005: Microfauna-macrofauna interaction in the seafloor: lessons from the tubeworm . PLoS Biol., 3 , 375-378. Boetius A. and Wenzhöfer F.; 2013: Seafloor oxygen consumption fuelled by methane from cold seeps . Nat. Geosci., 6 , 725–734. Cathles L.M., Su Z., and Chen D.; 2010: The physics of gas chimney and pockmark formation, with implications for assessment of seafloor hazards and gas sequestration . Mar. Pet. Geol., 27 , 82–91. Castello B., Selvaggi G., Chiarabba C. and Amato A.; 2006: CSI Catalogo della sismicità italiana 1981-2002, versione 1.1. INGV-CNT, Roma http://www.ingv.it/CSI/. Crutchley G.J., Pecher I., Gorman A.R., Henrys S., and Greinert J.; 2010: Seismic imaging of gas conduits beneath seafloor seep sites in a shallow marine gas hydrate province, Hikurangi Margin, New Zealand . Mar. Geol., 272 , 114–126. D’Agostino N., D’Anastasio E., Gervasi A., Guerra I., Nedimović M.R., Seeber L., and Steckler M.; 2011: Forearc extension and slow rollback of the Calabrian Arc from GPS measurements . Geophys. Res. Lett., 38 , L17304. Faccenna C., Molin P., Orecchio B., Olivetti V., Bellier O., Funiciello F., Minelli L., Piromallo C. and Billi A.; 2011: Topography of the Calabria subduction zone (southern Italy): Clues for the origin of Mt. Etna . Tectonics, 30 , TC1003. Gamberi F. and Rovere M., 2010. Mud diapirs, mud volcanoes and fluid flow in the rear of the Calabrian Arc Orogenic Wedge (southeastern Tyrrhenian sea) . Basin Res., 22 , 452–464. Judd A. and Hovland M.; 2007: Seabed fluid flow - the impact on Geology, Biology, and the Marine Environment . University Press, Cambridge. Klaucke I., Masson D.G., Petersen C.J., Weinrebe W., Ranero C.R.; 2008: Multifrequency geoacoustic imaging of fluid escape structures offshore Costa Rica: Implications for the quantification of seep processes . Geochemistry, Geophys. Geosystems, 9 , Q04010. Marcon Y., Ondreas H., Sahling H., Bohrmann G. and Olu K.; 2013: Fluid flow regimes and growth of a giant pockmark . Geology, 42 , 63–66. Naudts L., Greinert J., Artemov Y., Beaubien S.E. Borowski C. and De Batist M.; 2008: Anomalous sea-floor backscatter patterns in methane venting areas, Dnepr paleo-delta, NW Black Sea . Mar. Geol., 251 , 253–267. Nikolovska A., Sahling H., Bohrmann G.; 2008: Hydroacoustic methodology for detection, localization, and quantification of gas bubbles rising from the seafloor at gas seeps from the eastern Black Sea . Geochemistry, Geophys. Geosystems, 9 , Q10010. Oliver G., Rodrigues C.F. and Cunha M.R.; 2011: Chemosymbiotic bivalves from the mud volcanoes of the Gulf of Cadiz, NE Atlantic, with descriptions of new species of Solemyidae, Lucinidae and Vesicomyidae . Zookeys, 38 , 1–38. Ostanin I., Anka Z., di Primio R., BernalA.; 2013: Hydrocarbon plumbing systems above the Snøhvit gas field: Structural control and implications for thermogenic methane leakage in the Hammerfest Basin, SW Barents Sea . Mar. Pet. Geol., 43 , 127–146. Pondrelli S., Salimbeni S., Ekström G., Morelli A., Gasperini P. and Vannucci G.; 2006: The Italian CMT dataset from 1977 to the present . Phys. Earth Planet. Inter., 159 , 286–303. Römer M., Sahling H., Pape T., Bohrmann G. and Spieß V.; 2012: Quantification of gas bubble emissions from submarine hydrocarbon seeps at the Makran continental margin (offshore Pakistan) . J. Geophys. Res., 117 , C10015. 174 GNGTS 2014 S essione 1.2