FN Archimer Export Format PT J TI Fluid Seepage in Relation to Seabed Deformation on the Central Nile Deep-Sea Fan, Part 1: Evidence from Sidescan Sonar Data BT AF DANO, Alexandre PRAEG, Daniel MIGEON, SEBASTIEN AUGUSTIN, Jean-Marie CERAMICOLA, Silvia KETZER, Joao Marcelo AUGUSTIN, Adolfo Herbert DUCASSOU, Emmanuelle MASCLE, Jean AS 1:1;2:2;3:1;4:3;5:2;6:4;7:4;8:5;9:6; FF 1:;2:;3:;4:PDG-IMN-NSE-AS;5:;6:;7:;8:;9:; C1 Géoazur, UMR7329, UNS-UPMC-CNRS-OCA, Rue Albert Einstein, 06560, Valbonne, France OGS (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale), Borgo Grotta Gigante 42c, 34010, Trieste, Italy IFREMER, Technopôle Brest-Iroise, Plouzané, France Center of Excellence in Research and Innovation in Petroleum, Mineral Resources and Carbon Storage (CEPAC), Pontifical University of Rio Grande do Sul (PUCRS), Av. Ipiranga 6681, Prédio 96J, CEP 90619-900, Porto Alegre, RS, Brazil Université Bordeaux 1, UMR5805 EPOC, Avenue des facultés, 33405, Talence, France Géoazur, UMR7329, UNS-UPMC-CNRS-OCA, Porte de la Darse, Villefranche-sur-Mer, France C2 UNIV NICE, FRANCE OGS, ITALY IFREMER, FRANCE CEPAC, BRAZIL UNIV BORDEAUX, FRANCE UNIV NICE, FRANCE SI BREST SE PDG-IMN-NSE-AS IN WOS Ifremer jusqu'en 2018 copubli-europe copubli-int-hors-europe copubli-sud TC 2 TU Centre national de la recherche scientifique Institut de recherche pour le développement Observatoire de la côte d'azur Université Nice - Sophia-Antipolis Université Pierre et Marie Curie UR https://archimer.ifremer.fr/doc/00226/33752/37059.pdf LA English DT Article CR APINIL APINIL LEG1 APINIL LEG2 APINIL LEG3 BO Le Suroît DE ;Fluid seepage;Sediment deformation;Backscatter;Gas flares AB The central Nile Deep-Sea Fan contains a broad area of seabed destabilisation in association with fluid seepage: slope-parallel sediment undulations are associated with multibeam high-backscatter patches (HBPs) related to authigenic carbonates. During the 2011 APINIL campaign, a deep-towed sidescan and profiling system (SAR) was used to acquire high-resolution data along three transects across water depths of 1,700-2,650 m. Three seabed domains are distinguished, all developed within stratified sediments overlying mass-transport deposits (MTDs). Upslope of the undulations (<1,950 m), sidescan HBPs record focused fluid seepage via seabed cracks. In the western area of undulations, sidescan HBPs are distinct from intermediate-backscatter patches (IBPs) that extend up to 850 m parallel to the undulations, mainly along their downslope flanks; some contain sub-circular HBPs up to 300 m wide, three associated with smaller (<10 m) hydroacoustic gas flares. Focused fluid seeps are inferred to have shifted over time to form elongate carbonate pavements, preferentially along the footwalls of faults beneath the undulations that provide pathways for fluid flow. In contrast, in the eastern area of undulations, sidescan imagery reveal only slope-transverse furrows formed by turbulent flows, interpreted to indicate that fossil carbonates sampled during submersible operations have been exhumed by erosion. PY 2014 SO Advances in Natural and Technological Hazards Research SN 1878-9897 PU Springer Int Publishing Ag VL 37 UT 000339716900012 BP 129 EP 139 DI 10.1007/978-3-319-00972-8_12 ID 33752 ER EF