|
|
|
|
|
Ratzov, Gueorgui; Cattaneo, Antonio; Babonneau, Nathalie; Deverchere, Jacques; Yelles, Karim; Bracene, Rabah; Courboulex, Francoise. |
Ongoing evidence for earthquake clustering calls for records of numerous earthquake cycles to improve seismic hazard assessment, especially where recurrence times overstep historical records. We show that most turbidites emplaced at the Africa-Eurasia plate boundary off west Algeria over the past ∼8 k.y. correlate across sites fed by independent sedimentary sources, requiring a regional trigger. Correlation with paleoseismic data inland and ground motion predictions support that M ∼7 earthquakes have triggered the turbidites. The bimodal distribution of paleo-events supports the concepts of earthquake supercycles and rupture synchronization between nearby faults: 13 paleo-earthquakes underpin clusters of 3–6 events with recurrence intervals of ∼300–600 yr,... |
Tipo: Text |
|
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00254/36558/35105.pdf |
| |
|
|
Dan, Gabriela; Sultan, Nabil; Savoye, Bruno; Deverchere, Jacques; Yelles, Karim. |
The Algerian margin is a seismically active region, where during the last century, several large magnitude earthquakes took place. This study combines geotechnical and sedimentological data with numerical modelling to quantitatively assess the present-day slope stability of the Algerian margin. Geotechnical laboratory tests, such as cyclic triaxial tests, oedometric tests and vane shear tests were carried out on sediment cores collected on the study area. The liquefaction potential of a sediment column located about 30 km from the BoumerdSs earthquake epicentre of 21st May 2003 was evaluated theoretically for an earthquake of M (w) = 6.8. We show that thin sand and silt beds such as those described on recovered sediment cores are the main cause of sediment... |
Tipo: Text |
Palavras-chave: Earthquakes; Potential of liquefaction; Slope stability; Algerian margin. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6448.pdf |
| |
|
|
Domzig, Anne; Yelles, Karim; Le Roy, Charlotte; Deverchere, Jacques; Bouillin, Jean-pierre; Bracene, Rabah; De Lepinay, Bernard Mercier; Le Roy, Pascal; Calais, Eric; Kherroubi, Abdelaziz; Gaullier, Virginie; Savoye, Bruno; Pauc, Henri. |
We present new results from the MARADJA'03 cruise depicting the geological structures offshore central and western Algeria. Using swath bathymetry and seismic reflection data, we map and discuss the offshore limits of the Internal Zones corresponding to relics of the AIKaPeCa domain that drifted and collided the African plate during the Miocene. We identify large reverse faults and folds that reactivate part of these limits and are still active today. The morphology of the westernmost NE-SW margin suggests a former strike-slip activity accommodating a westward block translation responsible for the shift of the Internal Zones towards the Moroccan Rif. |
Tipo: Text |
Palavras-chave: Sismique réflexion; Bathymétrie multifaisceau; Évolution tectonique du Bassin méditerranéen; Néotectonique; Zones Internes; Marge Algérienne; Seismic reflection; Swath bathymetry; Tectonic evolution of the Mediterranean; Internal zones neotectonics; Algerian margin. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1211.pdf |
| |
|
|
Strzerzynski, Pierre; Deverchere, Jacques; Cattaneo, Antonio; Domzig, Anne; Yelles, Karim; De Lepinay, Bernard Mercier; Babonneau, Nathalie; Boudiaf, Azzedine. |
The Algerian margin has originated from the opening of the Algerian basin about 25-30 Ma ago. The central margin provides evidence for large-scale normal faults of Oligo-Miocene age, whereas transcurrent tectonics characterizes the western margin. A set of NW-SE oriented dextral transform faults was active during basin opening and divided the 600 km long central margin into segments of similar to 120-150 km. The upper Miocene, Plio-Quaternary, and present-day tectonic setting is, however, compressional and supports the occurrence of a margin inversion, a process still poorly documented worldwide. We show that the central Algerian margin represents a rare example of inverted margin, where the process of subduction inception is particularly well expressed... |
Tipo: Text |
Palavras-chave: Messinian salinity crisis; Western mediterranean sea; Northern algeria; Intraplate deformation; Incipient subduction; Plate kinematics; Salt tectonics; Boundary; Basin; Miocene. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00008/11883/9286.pdf |
| |
|
|
Babonneau, Nathalie; Cattaneo, Antonio; Savoye, Bruno; Barjavel, Guy; Deverchere, Jacques; Yelles, Karim. |
The Kramis deep-sea fan extends over 45 km at the base of the western Algerian continental slope between 2000 and 2550 m water depth and covers an area of approximately 1200 km2. The Kramis Fan was initiated after Messinian time, evolved during the Plio-Quaternary, and, is still active, as proved by submarine cable breaks during the 1954 Orléansville earthquake. The Kramis Fan is fed by two perpendicular canyons: the Kramis Canyon and the Khadra Canyon, merging in a single E–W-oriented channel confined at the foot of the slope. It is strongly asymmetric with a super-developed levee on the right-hand side of the channel, the Kramis Ridge. Based on recent multibeam, side-scan sonar, and sediment core data (Maradja, 2003 and 2005, Prisma, 2004, and Prisme,... |
Tipo: Text |
Palavras-chave: Algerian margin; Turbidity currents; Sediment waves; Scours. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00129/24021/21978.pdf |
| |
|
|
|