(Méthodes Potentielles, Imagerie Sismique) De Structures Géologiques
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
A Fundamental Precambrian–Phanerozoic Shift in Earth's Glacial
Tectonophysics 375 (2003) 353–385 www.elsevier.com/locate/tecto A fundamental Precambrian–Phanerozoic shift in earth’s glacial style? D.A.D. Evans* Department of Geology and Geophysics, Yale University, P.O. Box 208109, 210 Whitney Avenue, New Haven, CT 06520-8109, USA Received 24 May 2002; received in revised form 25 March 2003; accepted 5 June 2003 Abstract It has recently been found that Neoproterozoic glaciogenic sediments were deposited mainly at low paleolatitudes, in marked qualitative contrast to their Pleistocene counterparts. Several competing models vie for explanation of this unusual paleoclimatic record, most notably the high-obliquity hypothesis and varying degrees of the snowball Earth scenario. The present study quantitatively compiles the global distributions of Miocene–Pleistocene glaciogenic deposits and paleomagnetically derived paleolatitudes for Late Devonian–Permian, Ordovician–Silurian, Neoproterozoic, and Paleoproterozoic glaciogenic rocks. Whereas high depositional latitudes dominate all Phanerozoic ice ages, exclusively low paleolatitudes characterize both of the major Precambrian glacial epochs. Transition between these modes occurred within a 100-My interval, precisely coeval with the Neoproterozoic–Cambrian ‘‘explosion’’ of metazoan diversity. Glaciation is much more common since 750 Ma than in the preceding sedimentary record, an observation that cannot be ascribed merely to preservation. These patterns suggest an overall cooling of Earth’s longterm climate, superimposed by developing regulatory feedbacks -
Insights on the Crustal Evolution of the West African (Raton from Hf Isotopes in Detrital Zircons from the Anti-Atlas Belt
Insights on the crustal evolution of the West African (raton from Hf isotopes in detrital zircons from the Anti-Atlas belt a b c d b ]acobo Abati ,., Abdel Mohsine Aghzer , 1 , Axel Gerdes , ,2, Nasser Ennih • Departamento de Petrologfa y Geoquimica and Instituto de Geologia Econ6mica, Universidad Comp!utense/Consejo Superior de Investigaciones Cientificas. 28040 Madrid, Spain b Departament Ge% gie. Faculte des Sciences, Universite Chouaib Doukkali, EIJadida. Morocco c InstitutftirGeowissenschaften. Minera/ogie, Goethe-UniversityFrankfurt (GUF),Altenhoferallee 1. D-60438 Frankfurt amMain, Gennany d Department of Earth Sciences, SteIIenbosch University.Private BagXl. Matieland 7602, South Africa ABSTRACT The Lu-Hf isotopic composition of detrital zircons has been used to investigate the crustal evolution of the northern part of the West African (raton (WAC). The zircons were separated from six samples of siliciclastic sedimentary rocks from the main Neoproterozic stratigraphic units of the Anti-Atlas belt, from the SiIWa and Zenaga inliers. The data suggest that the north part of the WAC formed during three cycles of juvenile crust formation with variable amount of reworking of older crust. The younger group of zircons, with a main population clustering around 610 Ma, has a predominant juvenile character and Keyworili: evidences of moderate mixing with Paleoproterozoic and Neoarchean crust, which supports that most Anti-Atlas belt igneous and metamorphic rocks where zircons originally crystallized were formed in an ensialic mag Morocco Hfisotopes matic arc environment. The group of zircons in the age range 1.79-2.3 Ca corresponds to the major crust Detrital zircon forming event in the WAC: the Eburnian orogeny. -
Sa˜O Luıs Craton and Gurupi Belt (Brazil)
Sa˜o Luı´s Craton and Gurupi Belt (Brazil): possible links with the West African Craton and surrounding Pan-African belts E. L. KLEIN1,2 & C. A. V. MOURA3 1CPRM (Companhia de Pesquisa de Recursos Minerais)/Geological Survey of Brazil, Av. Dr. Freitas, 3645, Bele´m-PA, CEP 66095-110, Brazil (e-mail: [email protected]) 2Researcher at CNPq (Conselho Nacional de Desenvolvimento Cientı´fico e Tecnolo´gico) 3Laborato´rio de Geologia Isoto´pica/Para´-Iso, Universidade Federal do Para´, Centro de Geocieˆncias, CP 1611, Bele´m-PA, Brazil, CEP 66075-900 Abstract: The Sa˜o Luı´s Craton and the Palaeoproterozoic basement rocks of the Neoproterozoic Gurupi Belt in northern Brazil are part of an orogen having an early accretionary phase at 2240– 2150 Ma and a late collisional phase at 2080 + 20 Ma. Geological, geochronological and isotopic evidence, along with palaeogeographic reconstructions, strongly suggest that these Brazilian terrains were contiguous with the West African Craton in Palaeoproterozoic times, and that this landmass apparently survived subsequent continental break-up until its incorporation in Rodinia. The Gurupi Belt is an orogen developed in the southern margin of the West African–Sa˜o Luı´s Craton at c. 750–550 Ma, after the break up of Rodinia. Factors such as present-day and possible past geographical positions, the timing of a few well-characterized events, the structural polarity and internal structure of the belt, in addition to other indirect evidence, all favour correlation between the Gurupi Belt and other Brasiliano/Pan-African belts, especially the Me´dio Coreau´ domain of the Borborema Province and the Trans-Saharan Belt of Africa, despite the lack of proven physical links between them. -
2. Algérie-Dada & Zoumalé
LES WILAYAS DU GRAND SUD ALGERIEN : INFRASTRUCTURES ET POTENTIALITES ECONOMIQUES POUR LES ECHANGES SUB-SAHARIENS AVEC LA MALI ET LE NIGER Par Dadamoussa Lazhar, Zoumali Ahmed Ingénieurs des Travaux Publics Algérie 1. Introduction Le Sahara a été l'objet des ambitions coloniales de la France à partir des années1880 et se voyait intégrer, sur le papier, à l'Afrique occidentale française (AOF) en 1884. avant d'être reconnu possession française en 1890, par une convention signée avec le Royaume-Uni. La construction d'une série de forts servant de points d'appui aux troupes armées a permis ensuite en quelques années le contrôle presque complet de tout cet espace - seules quelques poches de résistance touareg et la Mauritanie devront attendre le début du XXe siècle pour se voir soumises. Ajoutons que deux autres puissance européennes ont égalent colonisé le Sahara : l'Espagne, d'abord, qui avait pris pied à l'Ouest du Sahara, dans la région du Rio de Oro, dès les années 1860, et l'Italie, engagée en Libye dans une guerre contre la Turquie qu'elle gagne en 1912, puis, qui en 1935, sous Mussolini, investit tout l'arrière-pays saharien jusqu'au Tchad, contestant à la France la bande d'Aouzou. A partir des années 1950 et jusqu'en 1975, la décolonisation aboutit au découpage du Sahara qui se trouve réparti entre plusieurs nouveaux États. Un partage qui se fait au détriment des populations sahariennes, d'où une partie des conflits qu'on a pu observer dans la région au cours des décennies suivantes. 1 Présentation générale de la zone d’étude Le tronçon algérien de la Transsaharienne sur plus de 3.000 km, enregistre d’importants travaux pour la transformer en autoroute Nord-Sud, parallèlement à des extensions dans l’extrême Sud pour désenclaver plusieurs localités de l’Ahaggar, lieu de tourisme saharien. -
De 15 300 Familles Concernées
L’Algérie profonde / Centre Opération de solidarité du RamadHan À TAMANRASSET Plus de 15 300 familles concernées ©D. R. Le recensement effectué à travers les dix municipalités de la wilaya de Tamanrasset fait état de 15 388 familles démunies concernées cette année par l'opération de solidarité du mois sacré du Ramadhan. Selon le rapport de la Direction de l'action sociale et de la solidarité de la wilaya (Dass), 5 862 familles nécessiteuses ont été recensées dans la commune de In-Salah, 3356 à Tamanrasset et 1 077 familles à Tin Zaouatine, suivie des communes de In Ghar (949), Tazrouk (877 familles), Fougaret Ezzoua (853), In Guezzam (732), Ideles (723), Abalessa (610) et, enfin, In Mguel avec 349 familles. Une enveloppe de 3,54 milliards de dinars a été consacrée à cette opération, a indiqué le DASS, Cheraibet Darouiche Abdallah. Ce dernier a précisé que la contribution du ministère de la Solidarité s'élève à 6,21 millions de dinars. En outre, une enveloppe financière de 8,24 millions de dinars a été dégagée du budget de la wilaya ainsi que des 12,95 millions de dinars alloués par les différentes municipalités. Le montant accordé dans le cadre du fonds de la zakat s'élève cette année à 8 millions de dinars. Cependant, la contribution des bienfaiteurs qui seront impliqués directement dans la distribution des kits alimentaires afin qu'ils s'assurent, eux-mêmes, de leurs donations, porterait ce montant à 4,97 milliards de dinars, selon les prévisions de la commission de préparation de l'opération de solidarité du Ramadhan, installée le 21 mai 2015. -
Back Matter (PDF)
Index Page numbers in italic denote figures. Page numbers in bold denote tables. Accra Plains Migmatite, correlation with Me´dio Coreau´ Bafia Group 86 domain 102–103, 114 Bahia–Gabon continental bridge 153, 154 Adamastor ocean Baixo Araguaia Supergroup 174, 299 closure 260, 265, 269, 270, 271, 271, 273 geochronology 184, 189, 190, 191 subduction 229, 231 Baltica Adamawa fault 92 palaeogeography 13–16, 14, 15, 17,22–23 Adamawa–Yade´ domain 85, 85, 87, 88,90–91 palaeomagnetic poles 10, 11 Afagados do Ingrazeira fault 72 Bambui Group 165, 201, 206 A´ gua Clara domain 241, 242 Bandeirinha Formation 36, 36, 37 A´ guas Belas–Caninde´ suite 80, 81 Bangweulu block 33, 43–45 Akanyaru Supergroup 33, 41–43, 45 Baoule´ –Mossi domain 142–144 Albian gap 379, 382, 384, 392 Barro Alto complex 204 Ale´m Paraı´ba shear zone 222 basalt, Brazilian margin 373 Algodo˜es Unit 53 basins Alto Moxoto´ terrane 72, 77, 92 sag Alto Pajeu´ terrane 72, 73, 77, 78, 92 Espirito Santo Basin 379 Amazonia Sa˜o Francisco craton 33, 34, 35–36, 39 palaeogeography 13–16, 14, 15, 16, 17, 21, 22–23 salt, Brazilian margin 366–370, 367, 375 palaeomagnetic poles 12,13 sedimentary Amazonian craton 102 Borborema Province 56 geochronology 177, 189, 191 Garupi Belt 141 Andrelaˆndia Group 164, 202, 205, 217 Parana´ –Cape–Karoo 319–337 Angola craton 4, 5, 223, 224, 225–226 rift, Brazilian margin, uplifted flanks 383–387 correlation with Cabo Frio terrane 292 Sa˜o Francisco–Congo craton 33–46 Apiaı´ terrane 214, 218, 221, 222–223, 229 Sa˜o Luı´s craton 140, 141 Apparent Polar Wander Path -
New Insights Into the Hercynian Orogeny, and Their Implications for the Paleozoic Hydrocarbon System in the Arabian Plate
GeoArabia, v. 14, no. 3, 2009, p. 199-228 Gulf PetroLink, Bahrain New insights into the Hercynian Orogeny, and their implications for the Paleozoic Hydrocarbon System in the Arabian Plate Mohammad Faqira, Martin Rademakers and AbdulKader M. Afifi ABSTRACT During the past decade, considerable improvements in the seismic imaging of the deeper Paleozoic section, along with data from new well penetrations, have significantly improved our understanding of the mid-Carboniferous deformational event. Because it occurred at the same time as the Hercynian Orogeny in Europe, North Africa and North America it has been commonly referred to by the same name in the Middle East. This was the main tectonic event during the late Paleozoic, which initiated or reactivated many of the N-trending block uplifts that underlie the major hydrocarbon accumulations in eastern Arabia. The nature of the Hercynian deformation away from these structural features was poorly understood due to inadequate seismic imaging and insufficient well control, along with the tectonic overprint of subsequent deformation events. Three Hercynian NE-trending arches are recognized in the Arabian Plate (1) the Levant Arch, which extended from Egypt to Turkey along the coast of the Mediterranean Sea, (2) the Al-Batin Arch, which extended from the Arabian Shield through Kuwait to Iran, and (3) the Oman-Hadhramaut Arch, which extended along the southeast coast of Oman and Yemen. These arches were initiated during the mid-Carboniferous Hercynian Orogeny, and persisted until they were covered unconformably by the Khuff Formation during the Late Permian. Two Hercynian basins separate these arches: the Nafud-Ma’aniya Basin in the north and Faydah- Jafurah Basin in the south. -
Bouda - Ouled Ahmed Timmi Tsabit - Sebâa- Fenoughil- Temantit- Temest
COMPETENCE TERRITORIALE DES COURS Cour d’Adrar Cour Tribunaux Communes Adrar Adrar - Bouda - Ouled Ahmed Timmi Tsabit - Sebâa- Fenoughil- Temantit- Temest. Timimoun Timimoun - Ouled Said - Ouled Aissa Aougrout - Deldoul - Charouine - Adrar Metarfa - Tinerkouk - Talmine - Ksar kaddour. Bordj Badji Bordj Badj Mokhtar Timiaouine Mokhtar Reggane Reggane - Sali - Zaouiet Kounta - In Zghmir. Aoulef Aoulef - Timekten Akabli - Tit. Cour de Laghouat Cour Tribunaux Communes Laghouat Laghouat-Ksar El Hirane-Mekhareg-Sidi Makhelouf - Hassi Delâa – Hassi R'Mel - - El Assafia - Kheneg. Aïn Madhi Aïn Madhi – Tadjmout - El Houaita - El Ghicha - Oued M'zi - Tadjrouna Laghouat Aflou Aflou - Gueltat Sidi Saâd - Aïn Sidi Ali - Beidha - Brida –Hadj Mechri - Sebgag - Taouiala - Oued Morra – Sidi Bouzid-. Cour de Ghardaïa Cour Tribunaux Communes Ghardaia Ghardaïa-Dhayet Ben Dhahoua- El Atteuf- Bounoura. El Guerrara El Guerrara - Ghardaia Berriane Sans changement Metlili Sans changement El Meniaa Sans changement Cour de Blida Cour Tribunaux Communes Blida Blida - Ouled Yaïch - Chréa - Bouarfa - Béni Mered. Boufarik Boufarik - Soumaa - Bouinan - Chebli - Bougara - Ben Khellil – Ouled Blida Selama - Guerrouaou – Hammam Melouane. El Affroun El Affroun - Mouzaia - Oued El Alleug - Chiffa - Oued Djer – Beni Tamou - Aïn Romana. Larbaa Larbâa - Meftah - Souhane - Djebabra. Cour de Tipaza Cour Tribunaux Communes Tipaza Tipaza - Nador - Sidi Rached - Aïn Tagourait - Menaceur - Sidi Amar. Kolea Koléa - Douaouda - Fouka – Bou Ismaïl - Khemisti – Bou Haroum - Chaïba – Attatba. Hadjout Hadjout - Meurad - Ahmar EL Aïn - Bourkika. Tipaza Cherchell Cherchell - Gouraya - Damous - Larhat - Aghbal - Sidi Ghilès - Messelmoun - Sidi Semaine – Beni Milleuk - Hadjerat Ennous. Cour de Tamenghasset Cour Tribunaux Communes Tamenghasset Tamenghasset - Abalessa - Idlès - Tazrouk - In Amguel - Tin Zaouatine. Tamenghasset In Salah Sans changement In Guezzam In Guezzam. -
Azawad and the Rights of Passage: the Role of Illicit Trade in the Logic of Armed Group Formation in Northern Mali by Francesco Strazzari
Report January 2015 Azawad and the rights of passage: the role of illicit trade in the logic of armed group formation in northern Mali By Francesco Strazzari Executive summary Over the past decade the displacement of narcotics supply lines has placed the remote and marginalised Sahara-Sahel region on the international drug route to the European market. Border control has become of primary importance, and an essential part of understanding the dynamics of competing political claims and armed movements. Secessionist, jihadist and statist political projects in northern Mali must now be interpreted in the light of dynamics of protection and extraction. In particular, the customary system of the droits de passage (rights of passage) has been transformed by the leap in scale and nature of traditional desert contraband. New actors have arisen, while others have been sidelined as various groups contend for the protection of illicit trade. This report explores the micro-level processes by which illicit economies have reshaped political and armed mobilisation. It explores the ways Tuareg traditions and grievances have been reconfigured under the influence of new illicit revenues. It also examines the Movement for Unity and Jihad in West Africa, a jihadist splinter group that took control of the city of Gao in 2012 when it aligned with business figures seeking to wrest control over trafficking from rival Tuareg groups. In this context, both nationalism and jihadism tend to mask acute social tensions in the region. Introduction aligned with the opportunities for reproduction and expan- At the heart of the conflict that flared up when the Malian sion in a region where one of the main competitive advan- army was attacked by Tuareg and other rebel formations in tages is that offered by extra-legal and criminal activities. -
Rapport Annuel 2010 TAM2
RAPPORT ANNUEL 2010 EXTENSION GÉOGRAPHIQUE DU PROJET INTÉGRÉ DE SANTÉ PUBLIQUE DANS LA WILAYA DE TAMANRASSET BASÉE À IN SALAH ALG 06 017 11 Sommaire 1 FICHE PROJET ..................................................................................................... 4 2 RÉSUMÉ ................................................................................................................ 6 2.1 APERÇU DE L ’INTERVENTION ........................................................................................ 6 2.2 POINTS SAILLANTS ....................................................................................................... 6 2.3 LEÇONS APPRISES ET RECOMMANDATIONS ................................................................... 7 3 EVOLUTION DU CONTEXTE................................................................................ 8 4 ANALYSE DE L’INTERVENTION.......................................................................... 9 4.1 ANCRAGE INSTITUTIONNEL ET MODALITÉS D ’EXÉCUTION ................................................ 9 4.2 OBJECTIF SPÉCIFIQUE ................................................................................................ 10 4.2.1 Indicateurs ..............................................................................................................................10 4.2.2 Analyse des progrès réalisés .................................................................................................11 4.2.3 Risques & hypothèses............................................................................................................13 -
RES WG Assessments of Mechanisms to Integrate RES in Isolated
RES WG Assessments of mechanisms to integrate RES in isolated electricity systems in MEDREG countries November 2013 MEDREG is supported by the European Union INDEX 1. Objectives of the document. ................................................................................................. 3 2. Introduction .............................................................................................................................. 3 3. Electricity generation technology. ...................................................................................... 4 4. Regulatory framework ............................................................................................................ 8 5. Conclusions ............................................................................................................................ 14 ANNEX (CASE STUDIES) .................................................................................................................. 16 Case Study 1: Isolated Systems in Algeria .............................................................................. 17 Case Study 2: Isolated Systems in France .............................................................................. 28 Case Study 3: Isolated Systems in Greece ............................................................................. 34 Case Study 4: Isolated Systems in Portugal ........................................................................... 43 Case Study 5: Isolated Systems in Spain ............................................................................... -
Journal Officiel
N° 62 Dimanche 25 Dhou El Hidja 1435 53ème ANNEE Correspondant au 19 octobre 2014 JOURNAL OFFICIEL DE LA REPUBLIQUE ALGERIENNE DEMOCRATIQUE ET POPULAIRE CONVENTIONS ET ACCORDS INTERNATIONAUX - LOIS ET DECRETS ARRETES, DECISIONS, AVIS, COMMUNICATIONS ET ANNONCES (TRADUCTION FRANÇAISE) Algérie ETRANGER DIRECTION ET REDACTION Tunisie SECRETARIAT GENERAL (Pays autres DU GOUVERNEMENT ABONNEMENT Maroc que le Maghreb) ANNUEL Libye WWW. JORADP. DZ Mauritanie Abonnement et publicité: IMPRIMERIE OFFICIELLE 1 An 1 An Les Vergers, Bir-Mourad Raïs, BP 376 ALGER-GARE Tél : 021.54.35..06 à 09 Edition originale….........…........…… 1070,00 D.A 2675,00 D.A 021.65.64.63 Fax : 021.54.35.12 Edition originale et sa traduction..... 2140,00 D.A 5350,00 D.A C.C.P. 3200-50 ALGER (Frais d'expédition en sus) TELEX : 65 180 IMPOF DZ BADR: 060.300.0007 68/KG ETRANGER: (Compte devises) BADR: 060.320.0600 12 Edition originale, le numéro : 13,50 dinars. Edition originale et sa traduction, le numéro : 27,00 dinars. Numéros des années antérieures : suivant barème. Les tables sont fournies gratuitement aux abonnés. Prière de joindre la dernière bande pour renouvellement, réclamation, et changement d'adresse. Tarif des insertions : 60,00 dinars la ligne 25 Dhou El Hidja 1435 25 Dhou El Hidja 1435 19 2octobre 2014 JOURNAL OFFICIELJOURNAL DE LA OFFICIEL REPUBLIQUE DE LA ALGERIENNEREPUBLIQUE NALGERIENNE° 62 N° 6219 octobre 2014 2 S O M M A I R E DECRETS Décret présidentiel n° 14-282 du 21 Dhou El Hidja 1435 correspondant au 15 octobre 2014 portant transfert de crédits au budget de fonctionnement du ministère des affaires étrangères.............................................................................................