GNGTS 2014 - Atti del 33° Convegno Nazionale

Conclusion. The comparison between theWS10 profiles in the west Sardinia margin and east Sardo-Provençal basin and the SF12 profiles in the south Balearic margin andAlgerian-Balearic basin let to make some consideration about the Messinian and post-Messinain geological events that characterize the west Mediterranean sea. The thickness of the Plio-Quaternary sequence highly depends on halokinetics, that produced local small basins between the diapirs and variable thinning above and around the diapirs. Regionally talking, the sequence in both the basins has generally a thickness of some hundreds of meters, locally reaching 1 s (TWT) that is to say more than 1 km. In the Sardo-Provençal basin the Plio-Quaternary thickness increases toward north-west, due to the sedimentary supply by the French rivers. The UU is thinner in the Algero-Balearic basin than in the Sardo Provençal basin testifying probable different subsidence rates. The presence of an intra UU halite layer in both the analyzed basins seems to confirm a further temporary sea level drop during the last MSC in the west Mediterranean basins, as hypothesized by Geletti et al. (2014). The halokinetic processes are distributed not homogeneously in the region and this depends on several different contributions. First of all the main element is the availability of salt: greater the amount of salt, easier will be the initiation of halokinetics. Another important element is the sedimentary load, generally increasing toward the central part of the deep basins, where we can observe the bigger diapir structures that can reach the sea bed with some thousands of meters in height. Finally, on the lower slope of the margins, in spite of thinner salt layers and sedimentary cover/load, the salt detachment produce small diapirs on the lower slope and several bigger diapirs in the deep basin, at the foot of the slope. Acknowledgments. We thank the OGS for the availability of the seismic dataset of the two projects West Sardinia and SALTFLU. The authors gratefully acknowledge Paradigm through the OGS Focus processing, Halliburton throught the University of Trieste Promax processing and Schlumberger through the University of Trieste Petrel academic grant for interpretation software. References Acosta J., Munoz A., Herranz P., Palomo C, Ballesteros M., Vaquero M. et al; 2001: Geodynamics of the Emile Baudot Escarpment and the Balearic Promontory, Western Mediterranean . Mar. Pet. Geol. 18, 349–369. doi:10.1016/ S0264-8172(01)00003-4 Camerlenghi A., Accettella D., Costa S., Lastras G., Acosta J., Canals M. and Wardell, N. ; 2009: Morphogenesis of the SW Balearic continental slope and adjacent abyssal plain, Western Mediterranean Sea . Int. J. Earth Sci., 98 , 735-750. Camerlenghi A., Wardell, N., Mocnik A., Del Ben A., Geletti R., and Urgeles, R.; 2014: Section 2 The Algero- Proven ç al Basin , in: Seismic Atlas of the Messinian Salinity Crisis markers in the Mediterranean Sea-Volume 2, Lofi J. et al., Commission for the Geological Map of the Word, submitted. Carminati E., Doglioni C. and Scrocca D.; 2004: Alps VsApennines. ����� ���� ��� ����� ���� ��� ��� ��� �� ��������� Spec. Vol. It. Geol. Soc. For the IGC 32 Florence- 2004. 141-151. CIESM; 2008: The Messinian Salinity Crisis from mega-deposits to microbiology - Aconsensus report N.33 in CIESM Workshop Monographs (F. Briand, Ed.), 168 pp, Monaco. CohenC.R.; 1980: Plate tectonicmodel for theOligo-Miocene evolution of the westernMediterranean . Tectonophysics, 68 , 283-311. Del Ben A., Mocnik A., Camerlenghi A., Geletti R. and Zgur F.; 2014: Section 9 Western Sardinia , in: Seismic Atlas of the Messinian Salinity Crisis markers in the Mediterranean Sea-Volume 2, Lofi J. et al., Commission for the Geological Map of the Word, submitted. Gelabert B., Sabat F. and Rodriguez-Perea A.; 1992: A structural outline of the Serra de Tramuntana of Mallorca (Balearic Islands) . Tectonophysics, 203 , 167-183. Geletti R., Zgur F., Del Ben A., Buriola F., Fais S., Fedi M., Forte E., Mocnik A., Paoletti V., Pipan M., Ramella R., Romeo R., and Romi A.; 2014: The Messinian Salinity Crisis: New seismic evidence in the West-Sardinian Margin and Eastern Sardo-Provençal basin (West Mediterranean Sea) . Marine Geology, 351 , 76-90. Hsü K. J., Cita M. B., and Ryan, W.B.F; 1973: The Origin of the Mediterranean Evaporites . In Ryan, W.B.F, Hsu, K. J., et al., Init. Repts. DSDP, 13, Pt. 2: Washington (U.S. Govt. Printing Office), 1203-1231. Lofi J., Déverchère J., Gaullier V., Gorini C., Guennoc P., Loncke L., Maillard A., Sage F., Thinon I.; with contr. J. 162 GNGTS 2014 S essione 1.2