Résumé : A partir de l'étude de trois oeuvres de Daniel Maximin, Patrick Chamoiseau et Raphaël Confiant), il s'agit de s'interroger sur les rapports entre histoire et écriture. En l'occurence, les procédures de mise en texte du chronotope algérien, si elles répondent à des logiques (poétiques, critiques) et à des sensibilités différentes renvoient bien à une même problématique, celle de l'identité antillaise. Par contraste, le "Détour" par l'Algérie de la guerre d'indépendance ou des années 70 permet aux trois romancier de préciser le sens du Discours antillais (Glissant) et de dessiner les contours d'un imaginaire fertile et souvent douloureux.
Through a close reading of three works by Daniel Maximin, Patrick Chamoiseau and Raphaël Confiant, we intend to examine the relationships between history and writing. With different logics and sensibilities, the texts under study implies a common issue : West Indian identity. In contrast with the caribbean situation, the "Detour" through Algeria of Independance war and of the 70' allows the three writers to specify the meaning of the "West Indian discourse" (Glissant) and to draw the outlines of a rich and often painful imaginary.
Algérie
Martinique

Droits : Ce document est protégé par le droit d'auteur. Il ne peut en aucun cas être utilisé sans l'autorisation de l'auteur et des ayant droits
recherch:HASH0177912e8bbd0fa9b6839f44

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The ultramafic rocks of the Collo region in northeastern Algeria crop out as “stratified” masses that cut across older metamorphic formations of the Petite Kabylie basement. Based on petrological compositions and mineralogical observations, these rocks are mainly peridotites and serpentinites. The peridotites are identified as lherzolites, but dunites may occur rarely. The lherzolites are composed of olivine, orthopyroxene, clinopyroxene and chromian spinel. Their chemical composition shows high MgO (34.4–37.5 wt%), Cr (0.14–0.27 wt%), Ni (0.14–0.26 wt%) and Co (34–133 ppm) contents and low CaO and Al2O3 concentrations (0.02–2.2 wt% and 0.5 to 2.8 wt%, respectively). The chromite, which represents approximately 1–3% of the rock, is ubiquitous and shows two different generations: primary millimetric euhedral crystals and secondary fine xenomorphic grains and interstitial aggregates. The primary chromites are alumino-ferro-magnesian crystals that show high Al2O3 (25.77%–27.36%) and MgO (10.70%–13.36%). Cr# (100 × Cr/(Al + Cr)) ranges from 45 to 48, and Mg# (100 × Mg/(Mg + Fe2+)) from 49 to 59. The secondary interstitial grains are iron-rich chromites. They show low Al2O3 (4.67%–9.54%) and MgO (4.60%–4.65%). Cr# is relatively high (77–88), whereas Mg# shows relatively low values, ranging from 22 to 25. Primary chromite and whole-rock chemistry show that the Collo ultramafic rocks belong to Alpine-type peridotites that were emplaced within an orogenic setting. The oxygen isotopic composition of both peridotites and chromites is consistent with their derivation from a mantle source (δ18O ranges from +3.0 to +5.9‰). Low δ18O values (<+4.4‰) are recorded in serpentinites and are attributed to the effect of serpentinization processes through high-temperature metasomatic fluids. Magnesite-bearing serpentinites show the lowest δ18O values. These are interpreted as the result of surface water input.
ISSN: 0899-5362

hal-01468003
https://hal.archives-ouvertes.fr/hal-01468003
DOI : 10.1016/j.jafrearsci.2016.10.012

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Miocene (17-11 Ma) magmatic activity in the Kabylies emplaced K-rich (and minor medium-K) calc-alkaline plutonic and volcanic rocks in five zones, delineating a ∼450 km long EW trending strip located along the northern coast of Algeria, between Annaba and Algiers. Their most likely source is the Kabylian subcontinental lithospheric mantle previously metasomatized during the Paleogene subduction of the Tethys oceanic lithosphere. Our preferred tectono-magmatic model involves a Tethyan slab detachment combined with African mantle delamination and crustal stacking, leading to the superimposition of the African continental crust over the Kabylian metasomatized lithospheric mantle. At ca. 17 Ma, the asthenospheric upwelling arising from lithospheric delamination and Tethyan slab tear triggered the thermal erosion of the latter mantle, inducing its partial melting. The corresponding mafic medium-K calc-alkaline magmas interacted with the African basement units during their ascent, generating intermediate to felsic K-rich calc-alkaline melts that display a characteristic trace element and isotopic crustal signature. Later on, slab tears propagated eastward and westward, promoting slab rollback perpendicular to plate convergence and inducing the emplacement of magmatic rocks of decreasing ages from central-eastern Algeria towards Tunisia and Morocco.
ISSN: 0899-5362

hal-01467997
https://hal.archives-ouvertes.fr/hal-01467997
DOI : 10.1016/j.jafrearsci.2016.10.005

Éditeur(s) : [S.l. : s.n.]
Extrait de : La traite des nègres et la croisade africaine comprenant la lettre encyclique de Léon XIII sur l'esclavage, le discours du cardinal Lavigerie à Paris, les témoignages des grands explorateurs : Livingstone, Cameron, Stanley, des missionnaires français, etc., ainsi que l'organisation des sociétés antiesclavagistes en France et en Europe (entre p. 30 et p. 32)
Résumé : Charles-Martial Allemand-Lavigerie, né à Bayonne (Basses-Pyrénées) le 31 octobre 1825, sacré évêque de Nancy le 22 mars 1863, nommé archevêque d'Alger par décret du 12 janvier 1867, préconisé le 27 mars suivant ; archevêque de Carthage en 1884, délégué apostolique pour les Missions du Sahara, du Soudan, de l'Afrique équatoriale, de Ste Anne de Jérusalem ; crée Cardinal-prêtre du titre de Ste Agnès-hors-les-murs, dans le consistoire du 27 mars 1882.
Siècle(s) traité(s) : 19
Permalien : http://www.manioc.org/images/LAM17014-0033i1
LAM17014-0033i1

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Avec son ouverture sur le marché mondial, la ville d’Alger, ou El-Djezaïr, (capitale de l’Algérie), est devenue une destination importante pour le tourisme d’affaires. Par ailleurs, sa côte, riche en plages et en stations balnéaires, reste très convoitée par un tourisme, souvent, massif et destructeur de l’identité de son environnement. D’où l’intérêt de penser à une stratégie de développement touristique visant la protection de son littoral. L’objectif de la présente contribution est la requalification du tourisme littoral à Alger par la réinterprétation de la forme de plaisance et d’agrément qui y a existé avant 1830. Il vise, également, la mise en valeur de son patrimoine territorial : fontaine, résidences d’été, et ainsi que les chemins naturels qui ont, depuis les temps les plus reculés, relié le port de la ville à son arrière-pays.En effet, avant 1830, El-Djezaïr était dotée d’un « Fahs » : un territoire très célèbre par ses « djenanes » (une sorte de résidences d’été faisant face à la mer et dotées de fabuleux jardins). Les « djenanes », souvent, destinés à être des musées déserts, peuvent constituer un potentiel singulier pour la requalification du tourisme littoral d’Alger. L’une des alternatives possibles serait leur reconversion en structures d’accueil pour le tourisme d’affaires, culturel et d’agrément... La contribution présente le cas de la « la villa du traité », un lieu commémoratif de la capitulation de la ville d’Alger en 1830, classée monument historique en 2003. Dans le cadre de l’opération de restauration et de mise en valeur achevée en janvier 2014, la villa et son jardin, situés dans l’enceinte d’une annexe au centre hospitalier de Birtraria (Alger), ont été proposés pour abriter un centre d’éthique et un lieu de manifestations scientifiques nationale et internationale en médecine.
With its opening on the world market, the city of Algiers, or El-Djezaïr, (capital of Algeria) has become an attractive destination for business tourism. Although, its coast, rich in beaches and seaside resorts, often undergoes a massive tourism that endangers its environment identity. Hence, it would be of first interest to set-up a touristic development strategy aiming the littoral safeguard. The main scope of this paper is the littoral tourism requalification in Algiers by reinterpreting the leisure and recreation facilities that existed there before 1830. Moreover, it focus on the valuation of its territorial heritage: fountains, summer residences, and mostly the natural paths that used to connect the city port to the hinterland since the earliest times.Indeed, before 1830, El-Djezaïr had its "Fahs”, a territory famous by its "djenanes": a kind of summer residences within fabulous gardens facing the sea. Often seemed like deserted museums, the "djenanes" could constitute a key opportunity coastal tourism requalification. One of the alternatives would be their reconversion into touristic structures for scientific, business, leisure and recreational tourism. The paper presents the case of “La Villa du Traité”, a commemorative place related to the capitulation of the city of Algiers in 1830. The place is proposed to become a center of ethics where national and international scientific events in Medicine could be held.
Alger

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.10829
http://journals.openedition.org/etudescaribeennes/10829

Éditeur(s) : Amer Geophysical Union
Résumé : 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 oceanic-type basement in the Algerian basin, and reveals a very narrow or absent transitional zone. Analysis of the deep structure of the margin indicates features inherited from its complex evolution: (1) an oceanic-type crust in the deep basin, (2) similarities with margins formed in a transform-type setting, (3) a progressive deepening of the whole sedimentary cover, and the thickening of the Plio-Quaternary sediments at the margin foot, coeval with (4) a downward flexure of the basement in the basin. These features argue for a multiphased evolution of the margin, including (1) an early stage of rifting and/or spreading, (2) a late transcurrent episode related to the westward migration of the Alboran domain, and (3) a diffuse Plio-Quaternary compressional reactivation of the margin.
Journal Of Geophysical Research-solid Earth (0148-0027) (Amer Geophysical Union), 2013-08 , Vol. 118 , N. 8 , P. 3899-3916

Droits : 2013. American Geophysical Union. All Rights Reserved.
http://archimer.ifremer.fr/doc/00152/26333/24412.pdf
DOI:10.1002/jgrb.50318
http://archimer.ifremer.fr/doc/00152/26333/

Éditeur(s) : Gravé par Lacaudrie
Extrait de : France pittoresque ou Description pittoresque, topographique et statistique des départements et colonies de la France : offrant en résumé, pour chaque département et colonie, l'histoire, les antiquités, la topographie, la météorologie, l'histoire naturelle, la division politique et administrative, la description générale et pittoresque du pays, la description particulière des villes, les bourgs, les communes et châteaux, celles des moeurs, coutumes et costumes, etc. ; avec des notes sur les langues, idiomes, et patois, sur l'instruction publique et la bibliographie locale, sur les hommes célèbres, etc. ; et des renseignements statistiques sur la population, l'industrie, le commerce, l'agriculture, la richesse territoriale, les impôts, etc., etc. ; accompagnée de la statistique générale de la France sous le rapport politique, militaire, judiciaire, financier, moral, médical, agricole, industriel et commercial. T. 3. (entre p. 260 et p. 261)
Siècle(s) traité(s) : 19
Droits : Domaine public
Permalien : http://www.manioc.org/images/SCH131900520i2
SCH131900520i2

Extrait de : Les Colonies françaises, petite encyclopédie coloniale (p. 504)
Résumé : Portrait de Georges Barthélemy Médéric Flamand (1861-1919). Géologue, professeur à l'École supérieure des sciences d'Alger, il fut directeur du Service géographique des territoires du sud de l'Algérie (en 1905.
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Communauté d'agglomération de La Rochelle. Médiathèque Michel-Crépeau
Permalien : http://www.manioc.org/images/MMC16023-1-0537i1
MMC16023-1-0537i1

Éditeur(s) : HAL CCSD Oxford University Press (OUP): Policy B - Oxford Open Option A Oxford University Press (OUP)
Résumé : International audience
Peridotite xenoliths exhumed by Quaternary alkaline magmatism in the Tahalgha district, southern Hoggar, represent fragments of the subcontinental lithospheric mantle beneath the boundary between the two major structural domains of the Tuareg Shield: the ‘Polycyclic Central Hoggar’ to the east and the ‘Western Hoggar’, or ‘Pharusian Belt’, to the west. Samples were collected from volcanic centres located on both sides of a major lithospheric shear zone at 4°35' separating these two domains. Although showing substantial variations in their deformation microstructures, equilibrium temperatures and modal and chemical compositions, the studied samples do not display any systematic changes of these features across the 4°35' fault. The observed variations rather record small-scale heterogeneities distributed throughout the study area and reflecting the widespread occurrence of vein conduits and metasomatized wall-rocks related to trans-lithospheric melt circulation during the Cenozoic. These features include partial annealing of pre-existing deformation microstructures, post-deformation metasomatic reactions, and trace-element enrichment, coupled with heating from 750–900°C (low-temperature lherzolites) to 900–1150°C (intermediate-T lherzolites and high-T harzburgites and wehrlites). Trace-element modelling confirms that the range of rare earth element (REE) variations observed in the Tahalgha clinopyroxenes may be accounted for by reactive porous flow involving a single stage of basaltic melt infiltration into a light REE (LREE)-depleted protolith. Whole-rock compositions record the final entrapment of disequilibrium metasomatic melts upon thermal relaxation of the veins–wall-rock system. The striking correlations between equilibrium temperatures and trace-element enrichment favor a scenario in which the high-temperature peridotites record advective heat transport along melt conduits, whereas the intermediate- and low-temperature lherzolites reflect conductive heating of the host Mechanical Boundary Layer. This indicates that the lithosphere did not reach thermal equilibrium, suggesting that the inferred heating event was transient and was rapidly erased by thermal relaxation down to the relatively low-temperature present-day geotherm. The low-T (<900°C) deformed lherzolites (porphyroclastic to equigranular) are characterized by only incipient annealing and LREE-depleted clinopyroxene compositions. They were only weakly affected by the Cenozoic events and could represent relatively well-preserved samples from rejuvenated Pan-African lithosphere. Extensive lithospheric rejuvenation occurred either regionally during the Pan-African orogeny, as a result of lithospheric delamination or thermomechanical erosion after thickening, or more locally along the meridional shear zones. The low-T Tahalgha lherzolites are comparable with lherzolites from Etang de Lherz, southern France, interpreted as lithospheric mantle rejuvenated by melt-induced refertilization during a late stage of the Variscan orogeny.
ISSN: 0022-3530

hal-01107410
https://hal.archives-ouvertes.fr/hal-01107410
DOI : 10.1093/petrology/egu056

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
A laser ablation ICP-MS U-Pb age of 17.84 +/- 0.12 Ma (late Burdigalian) was obtained from monazites separated from a leucocratic diatexite collected in close proximity to a small peridotite massif incorporated into the lower crustal sequence of the Edough Massif (north-eastern Algeria), a southern segment of the peri-Mediterranean Alpine Belt. Monazites extracted from a neighbouring deformed leucogranite intruding early Paleozoic phyllites yield a consistent age of 17.4 +/- 1.3 Ma. Zircons occurring in the same leucogranite, with magmatic characteristics, have an age of 308 +/- 7 Ma interpreted as dating magmatic crystallisation of the leucogranite and reflecting partial melting during the Hercynian orogeny. Low Th/U domains (Th/U<0.10) from the same grains substantiate recrystallisation during a younger metamorphic event whose upper age limit is 286 +/- 11 Ma. These results emphasize the polycyclic evolution of basement rocks preserved in the crystalline units of the western Mediterranean and indicate that part of their metamorphic features were inherited from older, Hercynian, events. Taken together with published Ar-Ar dates, the late Burdigalian age of monazites indicates a rapid cooling rate of c. 370 degrees C/Ma and is regarded as closely approximating the emplacement of the peridotites into the Hercynian basement. The monazite ages are significantly younger than those recorded for orogenic peridotites from the Betic-Rif oroctine and for the timing of lithospheric extension forming the Alboran sea. It is also younger than rifting and back-arc extension opening the Liguro-Provencal basin. The late Burdigalian age is interpreted as dating the incipient rifting event that opened the Algerian basin, which is consequently not a continuation of the Liguro-Provencal basin. At the scale of the western Mediterranean, these observations concur with current models supporting slab roll-back and an eastwards migration of extension in the western Mediterranean, but suggest that the Algerian basin opened as a result of torsion and stretching of the Thethyan slab due to its steepening under the Alboran microplate.
ISSN: 0009-2541

hal-00424511
https://hal.archives-ouvertes.fr/hal-00424511
DOI : 10.1016/j.chemgeo.2008.11.016

Éditeur(s) : Phot. Leroux
Extrait de : Les Colonies françaises, petite encyclopédie coloniale (p. 299)
Siècle(s) traité(s) : 19
Provenance : Communauté d'agglomération de La Rochelle. Médiathèque Michel-Crépeau
Permalien : http://www.manioc.org/images/MMC16023-1-0333i1
MMC16023-1-0333i1

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The Maghrebides, Betics and some parts of the Calabrian, NE Sicilian and Tuscan allochtons constitute dismembered fragments of the Alpine belt that resulted from the Cenozoic collision between Africa and Eurasia and the opening of the Western Mediterranean basin. Mineral and whole-rock geochemical analyses have been performed on three distinct outcrops of mantle material from the Edough Massif of NE Algeria, namely the Bou Maiza (BM) gabbros, the La Voile Noire (LVN) amphibolites and the Sidi Mohamed (SM) peridotites. In all samples, Sr isotopes are largely affected by seawater alteration (87Sr/86Sract. > 0.70384 and up to 0.70888) and cannot be used to evaluate the nature of the source reservoirs. SM peridotites display variable depleted mantle Nd isotopic signatures (εNdact. from + 7.0 to + 12.2) and geochemical features suggesting no significant chemical depletion as a result of partial melting and melt extraction (Mg# < 90; slightly LREE-depleted patterns with La/YbN = 0.33-0.39). These rocks are interpreted as parts of the subcontinental lithospheric mantle incorporated into the crustal units of the Edough Massif during the early stages of opening of the Algerian basin. BM gabbros and LVN amphibolites show geochemical signatures indicating derivation from a common Depleted Mantle reservoir (εNd > + 7.9) and are likely cogenetic, but without filiation with the SM peridotites. Pb isotopes indicate a contribution of sediments in the source reservoir, which is attributed to contamination solely by hydrous fluids released from a sedimentary component. This observation, together with a LILE-enrichment, suggests a back-arc basin environment. These results indicate that BM and LVN units were obducted onto the North African margin and subsequently fragmented, probably during doming and exhumation of the lower continental crust of the Edough massif. Doming resulted in opposite movements of the overlying oceanic units, southward for the BM units and northward for LVN amphibolites.
ISSN: 0040-1951

hal-01122777
https://hal.archives-ouvertes.fr/hal-01122777
DOI : 10.1016/j.tecto.2014.03.031

Éditeur(s) : Elsevier
Résumé : 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 mm/yr. Although no historical earthquakes are reported here, these fault segments could have been responsible for large (M similar to 7.5) events in the past. This young tectonic system further supports the hypothesis of subduction inception of the Neogene oceanic lithosphere in the context of the Africa-Eurasia convergence.
Marine Geology (0025-3227) (Elsevier), 2009-06 , Vol. 261 , N. 1-4 , P. 17-32

Droits : 2009 Published by Elsevier Inc.
http://archimer.ifremer.fr/doc/2009/publication-6850.pdf
DOI:10.1016/j.margeo.2008.05.016
http://archimer.ifremer.fr/doc/00000/6850/

Éditeur(s) : HAL CCSD Franco Angeli Edizioni
Résumé : International audience
Il 23 febbraio 2005 l'Assemblea Nazionale francese ha approvato la legge n. 158 «portant reconnaissance de la nation et contribution nationale en faveur des Français rapatriés», presentata da un gruppo di deputati dell'UMP (Unione per un movimento popolare) 1. Il testo intende riconoscere, e riaffermare, il debito morale dello Stato francese nei confronti dei " Pieds-noirs " (i francesi d'Algeria) e specialmente degli " Harkis " 2 , autoctoni reclutati dall'esercito francese in alcune unità ausiliarie durante la guerra d'Algeria. Con questa legge si vorrebbero dunque riconoscere i meriti degli Harkis, anche attraverso risarcimenti e riparazioni " morali " : gli Harkis e i loro orfani, infatti, percepiranno un sussidio di 2.800 euro l'anno, accompagnato da un capitale di 20.000 euro. La legge intende inoltre proteggere gli Harkis contro «gli insulti, la diffamazione e contro quelli che vorranno negare la loro tragedia». Oltre all'aumento delle compensazioni date ai Pieds-noirs, Harkis e veterani, la legge prevede la creazione di una fondazione per la memoria della guerra d'Algeria e dei combattimenti del Marocco e della Tunisia. A questa legge, che in origine avrebbe dovuto interessare " soltanto " la riconoscenza della nazione francese verso gli Harkis e i Pieds-noirs, sono stati aggiunti due nuovi articoli-1 e 4-che in un certo senso ne rivelano l'ambiguità di fondo.
ISSN: 1120-0650

hal-01673494
https://hal.univ-antilles.fr/hal-01673494
https://hal.univ-antilles.fr/hal-01673494/document
https://hal.univ-antilles.fr/hal-01673494/file/le%20colonie.pdf

Éditeur(s) : HAL CCSD Wiley-Blackwell Wiley
Résumé : The Late Early-to-Early Middle Eocene Zegdoumyidae are the oldest representatives of the order Rodentia to be known in Africa thus far. Despite the fragmentary nature of their fossil record, these early African rodents have been central in discussions surrounding the early evolutionary history of the Anomaluroidea clade (the living forms of which are the ‘scaly-tailed squirrels’, i.e. Anomaluridae). Here, we describe new dental remains attributable to Zegdoumys sbeitlai, a zegdoumyid from Tunisia (Djebel Chambi, CBI-1) dated at ca 50–45 Ma. The original material referred to this taxon was limited to four teeth documenting few dental loci. The new gathered material comprises practically all dental loci (except P4), thereby allowing a better description and characterization of this taxon. This Tunisian species is clearly distinct from its roughly coeval Algerian counterpart (Z. lavocati) or from the younger species recorded from Namibia (Z. namibiensis). We investigated the phylogenetic positions of Z. sbeitlai and the Zegdoumyidae in a high-level rodent phylogeny with a cladistic assessment of the dental evidence. Our results show that zegdoumyids represent the earliest offshoots (pectinately arranged) of a large clade that also encompasses the more advanced Eocene anomaluroids (here named Nementchamyidae), the Miocene Nonanomaluridae, and the stem and crown Anomaluridae. In this phylogenetic context, the species of Zegdoumys are the basalmost members of this large Anomaluroidea clade. Zegdoumyid taxa are therefore the oldest stem anomaluroid candidates, a statement which strengthens support for the hypothesis of the great antiquity of the Anomaluroidea clade in Africa. From a historical biogeography perspective, this assumption suggests that anomaluroids invaded Asia from Afro-Arabia sometime during the Middle Eocene, a dispersal event which was likely concomitant but opposite to the dispersals envisaged for the hystricognathous rodents and anthropoid primates from Asia to Afro-Arabia.
ISSN: 0300-3256

hal-01172007
https://hal.archives-ouvertes.fr/hal-01172007
DOI : 10.1111/zsc.12095

Éditeur(s) : Oxford Univ Press
Résumé : This study presents the results of a deep seismic survey across the north Algerian margin, based on the combination of 2-D multichannel and wide-angle seismic data simultaneously recorded by 41 ocean bottom seismometers deployed along a north-south line extending 180 km off Jijel into the Algerian offshore basin, and 25 land stations deployed along a 100-km-long line, cutting through the Lesser Kabylia and the Tellian thrust-belt. The final model obtained using forward modelling of the wide-angle data and pre-stack depth migration of the seismic reflection data provides an unprecedented view of the sedimentary and crustal structure of the margin. The sedimentary layers in the Algerian basin are 3.75 km thick to the north and up to 4.5-5 km thick at the foot of the margin. They are characterized by seismic velocities from 1.9 to 3.8 km s(-1). Messinian salt formations are about 1 km thick in the study area, and are modelled and imaged using a velocity between 3.7 and 3.8 km s(-1). The crust in the deep sea basin is about 4.5 km thick and of oceanic origin, presenting two distinct layers with a high gradient upper crust (4.7-6.1 km s(-1)) and a low gradient lower crust (6.2-7.1 km s(-1)). The upper-mantle velocity is constrained to 7.9 km s(-1). The ocean-continent transition zone is very narrow between 15 and 20 km wide. The continental crust reaches 25 km thickness as imaged from the most landward station and thins to 5 km over a less than 70 km distance. The continental crust presents steep and asymmetric upper- and lower-crustal geometry, possibly due to either asymmetric rifting of the margin, an underplated body, or flow of lower crustal material towards the ocean basin. Present-time deformation, as imaged from three additional seismic profiles, is characterized by an interplay of gravity-driven mobile-salt creep and active thrusting at the foot of the tectonically inverted Algerian margin.
Geophysical Journal International (0956-540X) (Oxford Univ Press), 2014-09 , Vol. 198 , N. 3 , P. 1486-1503

Droits : 2014 The Royal Astronomical Society
http://archimer.ifremer.fr/doc/00217/32836/32150.pdf
DOI:10.1093/gji/ggu179
http://archimer.ifremer.fr/doc/00217/32836/

Éditeur(s) : HAL CCSD Cambridge University Press (CUP)
Résumé : International audience
The Ben Zireg anticline NW of Bechar yields the currently most-important Frasnian succession on the northern margin of the Algerian Sahara. It represents 26.5 m of calcilutites which are attributed to the middle–late Frasnian. As the early Frasnian is not represented, the succession rests conformably on undifferentiated, probably late Givetian, substrate. Fine-scaled conodont biostratigraphy reveals a continuous sequence of Montagne Noire Zones 5–13, superseded by the earliest Famennian Lower triangularis Zone. The deposits are organized into 15 sedimentary cycles that are initially condensed and become dilated upwards. Conodont biofacies indicate an overall deepening towards the top of the section with an episode of slight shallowing at the MN11/12 transition marked by an increase of ancyrodellids, which is also seen in the Marhouma section of the Ougarta region (SW Algeria). Homogeneous calcareous microfacies with only a few shaly intercalations determine a predominantly oxygenated depositional environment on an outer platform, submarine rise or ramp setting. This is also indicated by relatively low sedimentation rates which are similar in selected sections from the Tafilalt platform, and contrast with those from the Marhouma trough and the Maider basin. Unlike other Frasnian successions south of the Atlas Fault, but similar to the Moroccan Meseta, the Upper Kellwasser horizon is clearly discriminated at Ben Zireg by an outstanding occurrence of black shales on top of the oxygenated latest Frasnian deposits.
ISSN: 0016-7568

hal-01217151
https://hal.archives-ouvertes.fr/hal-01217151
DOI : 10.1017/S0016756814000715

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : En Algérie l’intérêt porté au littoral est récent, la loi relative à la protection et à la valorisation du littoral date du 05 février 2002. Depuis, les pouvoirs publics ont consenti dans ce domaine des efforts effectifs et une politique très ambitieuse a été mise en œuvre.En effet, des plans d’aménagement côtiers ont été lancés à travers les 15 wilayas littorales que compte le pays et des commissariats nationaux du littoral ont été installés.Cependant, cette loi et ces instruments ont-ils modifié la gestion des espaces littoraux ? L’urbanisation a-t-elle été freinée ? Les dispositions de la loi sont-elles appliquées ? Ce sont des questions auxquelles nous allons tenter de répondre à travers le cas des communes littorales de la wilaya d’Oran, la plus importante ville côtière de l’ouest algérien.
In Algeria the interest took in the coastal areas is new, the law relating to the protection and development of the coastal areas dates from 5th February 2002. Since that time the authorities have made real efforts in this field and a very ambitious policy has been implemented.Indeed, management schemes have been launched for 15 coastal towns within the country and national commissions devoted to the coastal areas have been installed.However, have this law and these instruments changed the management of the coastal areas? Has the urbanization stopped? Is the law implemented?These are the questions we will try to answer by observing the coastal areas of Oran, the most important coastal city of western part Algeria.
Algérie
Oran

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.5959
http://journals.openedition.org/etudescaribeennes/5959

Éditeur(s) : Soc Francaise D Ichtyologie
Résumé : A total of 664 Boops Boops (Linnaeus, 1758) and 823 Mullus barbatus barbatus Linnaeus, 1758 from the east coast of Algeria were examined to study their parasitofauna. We collected eleven parasitic species (two monogeneans, three copepods, five isopods and one Branchiura) from B. boops, and four parasitic species (two copepods and two isopods) from M. barbatus barbatus. Five species were reported for the first time in Algeria. The site of attachment on the host and the degree of specificity varied according to the parasite species while the infestation rate changed according to the month and the host size. The parasitism did not show a significant negative impact on the biological parameters of the fish host.
Au total, 664 Boops Boops (Linnaeus, 1758) et 823 Mullus barbatus barbatus Linnaeus, 1758 capturés le long du littoral Est de l’Algérie ont été examinés afin d’étudier leur parasitofaune. Sur B. boops, nous avons récolté 11 espèces d’ectoparasites (deux monogènes, trois copépodes, cinq isopodes et un Branchioura), et quatre espèces sur M. barbatus barbatus (deux copépodes et deux isopodes). Parmi les 14 ectoparasites identifiés, cinq ont été récoltés pour la première fois en Algérie. Le site d’attache sur l’hôte et le degré de spécificité étaient différents selon les espèces de parasites. Le taux d’infestation variait selon le mois et la taille de l’hôte. Le parasitisme n’a induit aucun impact négatif significatif sur les paramètres biologiques des poissons hôtes.
Cybium (0399-0974) (Soc Francaise D Ichtyologie), 2013-04 , Vol. 37 , N. 1-2 , P. 59-66

Droits : 2013 Société Française d'Ichtyologie
http://archimer.ifremer.fr/doc/00148/25901/23918.pdf
http://archimer.ifremer.fr/doc/00148/25901/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
We use velocities from 65 continuous stations and 31 survey-mode GPS sites as well as kinematic modeling to investigate present day deformation along the Africa-Iberia plate boundary zone in the western Mediterranean region. The GPS velocity field shows southwestward motion of the central part of the Rif Mountains in northern Morocco with respect to Africa varying between 3.5 and 4.0 mm/yr, consistent with prior published results. Stations in the southwestern part of the Betic Mountains of southern Spain move west-southwest with respect to Eurasia (similar to 2-3 mm/yr). The western component of Betics motion is consistent with partial transfer of Nubia-Eurasia plate motion into the southern Betics. The southward component of Betics motion with respect to Iberia is kinematically consistent with south to southwest motion of the Rif Mountains with respect to Africa. We use block modeling, constrained by mapped surface faults and seismicity to estimate the geometry and rates of strain accumulation on plate boundary structures. Our preferred plate boundary geometry includes one block between Iberia and Africa including the SW Betics, Alboran Sea, and central Rif. This geometry provides a good fit to the observed motions, suggesting a wide transpressive boundary in the westernmost Mediterranean, with deformation mainly accommodated by the Gloria-Azores fault system to the West and the Rif-Tell lineament to the East. Block boundaries encompass aspects of earlier interpretations suggesting three main deformation styles: (i) extension along the NE-SW trending Trans-Alboran shear zone, (ii) dextral strike-slip in the Betics corresponding to a well defined E-W seismic lineament, and (iii) right lateral strike-slip motion extending West to the Azores and right-lateral motion with compression extending East along the Algerian Tell. We interpret differential motion in the Rif-Alboran-Betic system to be driven both by surface processes related the Africa-Eurasia oblique convergence and sub-crustal dynamic processes associated with the long history of subduction of the Neotethys ocean lithosphere. The dextral slip identified in the Betic Mountains in Southern Spain may be related to the offshore fault that produced the Great 1755 Lisbon Earthquake, and as such may represent a significant seismic hazard for the West Mediterranean region.
ISSN: 0012-821X

hal-00618337
https://hal.archives-ouvertes.fr/hal-00618337
DOI : 10.1016/j.epsl.2011.05.048