GNGTS 2017 - 36° Convegno Nazionale

GNGTS 2017 S essione 3.1 581 parte sommitale (Fig. 3) ed è caratterizzato da una serie di faglie normali che riflettono la tettonica estensionale avvenuta sino al Miocene. In corrispondenza dei prismi di accrezione esterni dell’Arco Calabro e della Dorsale Mediterranea si verificano fenomeni di tettonica salina, che mascherano la risposta sismica delle formazioni sepolte alla base della sequenza evaporitica. Il processo di deformazione compressiva, che rappresenta la fase tettonica più recente, è largamente acuito dalla presenza dello spessore evaporitico, a causa del basso attrito che lo caratterizza. Riconoscimenti Il profilo sismico multicanale CROP M2B è stato fornito dal Database CROP ( www.crop.cnr.it) , che si occupa del recupero, manutenzione e distribuzione di questo patrimonio. Bibliografia Ben-Avraham Z., Woodside J., Lodolo E., Gardosh M., Grasso M., Camerlenghi A., and Vai G. B.; 2006: Eastern Mediterranean basin systems . Geological Society, London, Memoirs, 32(1), 263-276. Dal Cin M., Del Ben A., Mocnik A., Accaino F., Geletti R., Wardell N., Zgur F., and Camerlenghi A.; 2016: Seismic imaging of Late Miocene (Messinian) evaporites from Western Mediterranean back-arc basins. Petroleum Geoscience,  22 (4), p. 297-308. Gutscher M. A., Kopp H., Krastel S., Bohrmann G., Garlan T., Zaragosi S., Klaucke I., Wintersteller P., Loubrieu B., Le Fau Y., San Pedro L., Dominguez S., Rovere M., Mercier de Lepinay B., Ranero C. and Sallares V. (2017). Active tectonics of the Calabrian subduction revealed by new multi-beam bathymetric data and high-resolution seismic profiles in the Ionian Sea (Central Mediterranean) . Earth and Planetary Science Letters, 461 , 61-72. Lofi J., Sage F., Déverchère J., Loncke L., Maillard A., Gaullier V., Thinon I., Gillet H., Guennoc P. and Gorini C.; 2011: Refining our knowledge of the Messinian salinity crisis records in the offshore domain through multi-site seismic analysis . Bulletin de la Société géologique de France, 182 (2), 163-180. Reston T. J., Fruehn J., von Huene R. and IMERSE Working Group; 2002: The structure and evolution of the western Mediterranean Ridge . Marine Geology, 186 (1), 83-110. Zhu, J., Lines, L. and Gray, S.; 1998: Smiles and frowns in migration/velocity analysis . Geophysics, 63 (4), p. 1200- 1209. THERMO-COMPOSITIONAL VARIABILITY OF THE AUSTRALIAN PLATE FROM A JOINT ANALYSIS OF SEISMIC GRAVITY DATA M. Tesauro 1,2 , M.K. Kaban 3 , A.R.A. Aitken 4 1 Department of Mathematics and Geosciences, University Trieste, Italy 2 Department of Earth Sciences, University Utrecht, The Netherlands 3 GeoForschungsZentrum (GFZ), Potsdam, Germany 4 School of Earth Sciences, The University of Western Australia, Perth, Australia Introduction. The Australian plate has a long and complex tectonic history and its crust and upper mantle of the Australian continent has been deeply investiagted in the last two decades using a variety of geophysical methods (e.g., Kennet et al ., 2011). The Australian continental crust was accreted in three major episodes from the Archean cratons in the west to Phanerozoic provinces in the east. Different Archean crustal elements were assembled into three major cratonic zones in the Proterozoic: West Australia, the North Australian Craton, and the South Australian Craton were formed by 1830 Ma. These cratonic elements were joined to the Rodinian supercontinent by 1300–1100 Ma (Cawood and Korsch, 2008), which broke up around 800 Ma. Subsequently, the fold belt structures of the Phanerozoic Tasman Orogen of the eastern third of Australia were accreted onto the eastern margin of the Precambrian cratons in the late Palaeozoic in a series of stages (e.g. Direen and Crawford, 2003). In the Mesozoic, Australia was the continental margin of the subducting Pacific Plate and subsequently a chain of hotspot-related volcanism has developed through eastern Australia. The eastern margin of Australia has been influenced by seafloor spreading in the Tasman Sea from 80 Myr and backarc spreading in the Coral Sea. The upper mantle of the Australian plate is