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| Registros recuperados: 17 | |
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| Babonneau, Nathalie; Cattaneo, Antonio; Ratzov, Gueorgui; Deverchere, Jacques; Yelles-chaouche, Abdelkarim; Lateb, Tassadit; Bachir, Roza Si. |
| Northern Algeria is threatened by moderate to large magnitude earthquakes resulting from the slow convergence between the African and European plates. Main active faults are located offshore along the Algerian coast, as exemplified by the 2003 Mw 6.9 Boumerdès earthquake. This event triggered numerous and widespread turbidity currents over ∼ 150 km along strike in the Algerian basin (reaching 2800 m of water depth) and demonstrates the multi-source and multi-path characteristics of earthquake-triggered turbidity flows along this margin segment. We rely on the sedimentological analysis of five cores located at the toe of the Algiers margin, close to the 2003 cable break sites, to explore the potential for Holocene turbidite paleoseismology. Radiocarbon... |
| Tipo: Text |
Palavras-chave: Algerian margin; Marine paleoseismology; Turbidite; Holocene. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00356/46701/46563.pdf |
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| Tiberi, C.; Gautier, S; Ebinger, C.; Roecker, S.; Plasman, M.; Albaric, J.; Deverchere, Jacques; Peyrat, S.; Perrot, Julie; Wambura, R. Ferdinand; Msabi, M.; Muzuka, A.; Mulibo, G.; Kianji, G.. |
| We present a joint analysis of newly acquired gravity and teleseismic data in the North Tanzanian Divergence, where the lithospheric break-up is at its earliest stage. The impact of a mantle upwelling in more mature branches of the East African Rift has been extensively studied at a lithospheric scale. However, few studies have been completed that relate the deep-seated mantle anomaly detected in broad regional seismic tomography with the surface deformation observed in the thick Archaean Pan-African suture zone located in North Tanzania. Our joint inversion closes the gap between local and regional geophysical studies, providing velocity and density structures from the surface down to ca. 250 km depth with new details. Our results support the idea of a... |
| Tipo: Text |
Palavras-chave: Gravity anomalies and Earth structure; Africa; Joint inversion; Seismic tomography; Intra-plate processes. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00637/74944/76038.pdf |
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| Cattaneo, Antonio; Babonneau, Nathalie; Ratzov, G.; Dan-unterseh, G.; Yelles, K.; Bracene, R.; De Lepinay, B. Mercier; Boudiaf, A.; Deverchere, Jacques. |
| Shaking by moderate to large earthquakes in the Mediterranean Sea has proved in the past to potentially trigger catastrophic sediment collapse and flow. On 21 May 2003, a magnitude 6.8 earthquake located near BoumerdSs (central Algerian coast) triggered large turbidity currents responsible for 29 submarine cable breaks at the foot of the continental slope over similar to similar to 150 km from west to east. Seafloor bathymetry and backscatter imagery show the potential imprints of the 2003 event and of previous events. Large slope scarps resulting from active deformation may locally enhance sediment instabilities, although faults are not directly visible at the seafloor. Erosion is evident at the foot of the margin and along the paths of the numerous... |
| Tipo: Text |
Palavras-chave: Western mediterranean sea; Cascadia subduction zone; Turbidity current; Zemmouri earthquake; Sedimentary processes; Submarine landslides; Northern algeria; Margin; Gps; Boundary. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00098/20959/18571.pdf |
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| 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 |
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| Kherroubi, Abdelaziz; Deverchere, Jacques; Yelles, Abdelkarim; De Lepinay, Bernard Mercier; Domzig, Anne; Cattaneo, Antonio; Bracene, Rabah; Gaullier, Virginie; Graindorge, David. |
| We describe for the first time a set of large active thrusts and folds near the foot of the easternmost Algerian margin, Western Mediterranean, from swath bathymetry and high-resolution seismic data acquired in 2005 during the Maradja2/Samra cruise. This active system resumes a previous passive margin and creates growth strata deposition on the limbs of large folds, resulting in the development of perched basins at the foot of the margin since less than similar to 1 Ma. They form a set of overlapping fault segments verging toward the Algerian basin, in a way similar to what has been observed off eastern Algiers on the rupture zone of the 2003 Mw 6.8 Boumerdes earthquake. The horizontal shortening rate across large folds is estimated to be of the order of 1... |
| Tipo: Text |
Palavras-chave: Subduction inception; Africa Eurasia convergence; Seismic reflection; Seismic hazards; Growth strata; Folding; Active faulting; Annaba; Algerian margin. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6850.pdf |
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| Dobrynina, A. A.; Sankov, V. A.; Deverchere, Jacques; Chechelnitsky, V. V.. |
| Attenuation of seismic waves in the crust and the upper mantle has been studied in three global rift systems: the Baikal rift system (Eurasia), the North Tanzanian divergence zone (Africa) and the Basin and Range Province (North America). Using the records of direct and coda waves of regional earthquakes, the single scattering theory [Aki, Chouet, 1975], the hybrid model from [Zeng, 1991] and the approach described in [Wennerberg, 1993], we estimated the seismic quality factor (QC), frequency parameter (n), attenuation coefficient (delta), and total attenuation (QT). In addition, we evaluated the contributions of two components into total attenuation: intrinsic attenuation (Qi), and scattering attenuation (Qsc). Values of QC are strongly dependent on the... |
| Tipo: Text |
Palavras-chave: Baikal rift system; East African rift system; North American Basin and Range Province; Attenuation of seismic waves; Seismic quality factor; Seismicity; Coda waves; Intrinsic attenuation; Scattering attenuation; Heat flow. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00638/75049/75658.pdf |
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| 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 |
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| Plasman, M.; Tiberi, C.; Ebinger, C.; Gautier, S; Albaric, J.; Peyrat, S.; Deverchere, Jacques; Le Gall, B.; Tarits, Pascal; Roecker, S.; Wambura, F.; Muzuka, A.; Mulibo, G.; Mtelela, K.; Msabi, M.; Kianji, G.; Hautot, S.; Perrot, J.; Gama, R.. |
| Rifting in a cratonic lithosphere is strongly controlled by several interacting processes including crust/mantle rheology, magmatism, inherited structure and stress regime. In order to better understand how these physical parameters interact, a 2 yr long seismological experiment has been carried out in the North Tanzanian Divergence (NTD), at the southern tip of the eastern magmatic branch of the East African rift, where the southward-propagating continental rift is at its earliest stage. We analyse teleseismic data from 38 broad-band stations ca. 25 km spaced and present here results from their receiver function (RF) analysis. The crustal thickness and Vp/Vs ratio are retrieved over a ca. 200 x 200 km(2) area encompassing the South Kenya magmatic rift,... |
| Tipo: Text |
Palavras-chave: Time-series analysis; Continental tectonics: extensional; Africa; Crustal imaging. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00638/75026/75673.pdf |
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| 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 |
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| Aidi, Chafik; Beslier, Marie-odile; Yelles-chaouche, Abdel Karim; Klingelhoefer, Frauke; Bracene, Rabah; Galve, Audrey; Bounif, Abdallah; Schenini, Laure; Hamai, Lamine; Schnurle, Philippe; Djellit, Hamou; Sage, Francoise; Charvis, Philippe; Deverchere, Jacques. |
| During the Algerian-French SPIRAL survey aimed at investigating the deep structure of the Algerian margin and basin, two coincident wide-angle and reflection seismic profiles were acquired in central Algeria, offshore Greater Kabylia, together with gravimetric, bathymetric and magnetic data. This ~260 km-long offshore-onshore profile spans the Balearic basin, the central Algerian margin and the Greater Kabylia block up to the southward limit of the internal zones onshore. Results are obtained from modeling and interpretation of the combined data sets. The Algerian basin offshore Greater Kabylia is floored by a thin oceanic crust (~4 km) with P-wave velocities ranging between 5.2 and 6.8 km/s. In the northern Hannibal High region, the atypical 3-layer... |
| Tipo: Text |
Palavras-chave: Mediterranean Sea; Algerian margin; Crustal structure; Tectonic inversion; Post-accretion magmatism; Deep seismics. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00425/53677/54519.pdf |
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| Bouyahiaoui, B.; Sage, F.; Abtout, A.; Klingelhoefer, Frauke; Yelles-chaouche, K.; Schnuerle, P.; Marok, A.; Deverchere, Jacques; Arab, M.; Galve, A.; Collot, J.y.. |
| We determine the deep structure of the eastern Algerian basin and its southern margin in the Annaba region (easternmost Algeria), to better constrain the plate kinematic reconstruction in this region. This study is based on new geophysical data collected during the SPIRAL cruise in 2009, which included a wide-angle, 240-km-long, onshore–offshore seismic profile, multichannel seismic reflection lines and gravity and magnetic data, complemented by the available geophysical data for the study area. The analysis and modelling of the wide-angle seismic data including refracted and reflected arrival travel times, and integrated with the multichannel seismic reflection lines, reveal the detailed structure of an ocean-to-continent transition. In the deep basin,... |
| Tipo: Text |
Palavras-chave: Tomography; Composition of the oceanic crust; Continental margins; Divergent; Africa. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00269/38016/36103.pdf |
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| Deverchere, Jacques; Yelles, K; Domzig, Anne; Mercier De Lepinay, B; Bouillin, J.p.; Gaullier, V; Bracene, R; Calais, E; Savoye, Bruno; Kherroubi, A; Le Roy, P; Pauc, H; Dan, Gabriela. |
| [1] We investigate the active seismogenic fault system in the area of the 2003 Mw 6.9 Boumerdes earthquake, Algeria, from a high-resolution swath bathymetry and seismic survey. A series of 5 main fault-propagation folds similar to20-35 km long leave prominent cumulative escarpments on the steep slope and in the deep basin. Fault activity creates Plio-Quaternary growth strata within uplifted areas such as a rollover basin on the slope and piggyback basins in the deep ocean. Most thrusts turn to fault-propagation folds at the sub-surface and depict ramp-flat trajectories. We find that the two main slip patches of the 2003 Mw 6.9 Boumerdes earthquake are spatially correlated to two segmented cumulative scarps recognized on the slope and at the foot of the... |
| Tipo: Text |
Palavras-chave: Continental margin; Sismicity; Tectonophysics. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-743.pdf |
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| 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 |
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| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00254/36558/35105.pdf |
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| Deverchere, Jacques; De Lepinay, Bernard Mercier; Cattaneo, Antonio; Strzerzynski, Pierre; Calais, Eric; Domzig, Anne; Bracene, Rabah. |
| Although often difficult to characterize, the relationship between a seismic rupture, its aftershock sequence, and cumulative subsurface or surface faulting or folding is an important challenge to modern seismology and seismotectonics. Among other benefits, it helps document fault length, slip, and magnitude relationships, reconstruct the evolution of the rupture process through historical and prehistorical times and identify the complexity of the deformation in its path toward the surface. This approach is a prerequisite to any seismic hazard assessment but is particularly difficult for faults whose surface trace projects offshore. A specific effort to identify and quantify the source parameters of large earthquakes in coastal areas is therefore needed,... |
| Tipo: Text |
Palavras-chave: Boumerdès-Zemmouri earthquake; Deformation; Kinematics; Margin. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00003/11440/7994.pdf |
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| Lepretre, Angelique; Klingelhoefer, Frauke; Graindorge, David; Schnurle, Philippe; Beslier, M. O.; Yelles, K.; Deverchere, Jacques; Bracene, R.. |
| The origin of the Algerian margin remains one of the key questions still discussed in the Western Mediterranean sea, due to the imprecise nature and kinematics of the associated basin during the Neogene. For the first time, the deep structure of the Maghrebian margin was explored during the SPIRAL seismic survey. In this work, we present a N-S transect off Tipaza (west of Algiers), a place where the margin broadens due to a topographic high (Khayr-al-Din Bank). New deep penetration seismic profiles allow us to image the sedimentary sequence in the Algerian basin and the crustal structure at the continent-ocean boundary. Modeling of the wide-angle data shows thinning of the basement, from more than 15km in the continental upper margin to only 5–6km of... |
| Tipo: Text |
Palavras-chave: Algerian margin; Crustal structure; Wide-angle seismic data; Multiphased tectonic evolution; Western Mediterranean back-arc basins; Contractional reactivation. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00152/26333/24412.pdf |
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| 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 |
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| Registros recuperados: 17 | |
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