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Geometrie Structurale Et Evolution Tectonique De La Ceinture De Roches Vertes De Labitibi Partie Nord Ouest
Download Geometrie Structurale Et Evolution Tectonique De La Ceinture De Roches Vertes De Labitibi Partie Nord Ouest full books in PDF, epub, and Kindle. Read online Geometrie Structurale Et Evolution Tectonique De La Ceinture De Roches Vertes De Labitibi Partie Nord Ouest ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Géométrie structurale et évolution tectonique de la ceinture de roches vertes de l'Abitibi (partie nord-ouest) by : Sylvain Lacroix
Download or read book Géométrie structurale et évolution tectonique de la ceinture de roches vertes de l'Abitibi (partie nord-ouest) written by Sylvain Lacroix and published by . This book was released on 1998 with total page 900 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Evolution of Archean Crust and Early Life by : Yildirim Dilek
Download or read book Evolution of Archean Crust and Early Life written by Yildirim Dilek and published by Springer. This book was released on 2013-11-26 with total page 421 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an integrated approach to the study of the evolution of the Archean lithosphere, biosphere and atmosphere, and as such it is a unique contribution to our understanding of the early Earth and life. The structural and geochemical make-up of both the oceanic and continental crust of the Archean Earth is documented in some case studies of various cratons, and the implications of the Phanerozoic plate and plume tectonic processes for the Archean geology are discussed in several chapters in the book. All chapters are process-oriented and data-rich, and reflect the most recent knowledge and information on the Archean Earth. The interdisciplinary approach of examining the evolution of the Archean crust, oceans, and life that we adopt in this book sets it apart from previous publications on Precambrian geology. The book will be attractive to researchers in academia and in industry, and to senior undergraduate students, graduate students and faculty in earth and natural sciences.
Book Synopsis Étude de la géométrie et des mouvements de la faille de Doda (sous-province de l'Abitibi) by : Hamid Goghrod
Download or read book Étude de la géométrie et des mouvements de la faille de Doda (sous-province de l'Abitibi) written by Hamid Goghrod and published by . This book was released on 1993 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Dissertation Abstracts International by :
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1999 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis CIM Bulletin by : Canadian Institute of Mining and Metallurgy
Download or read book CIM Bulletin written by Canadian Institute of Mining and Metallurgy and published by . This book was released on 2001 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Quarterly Bulletin of the Canadian Mining Institute by : Canadian Institute of Mining, Metallurgy and Petroleum
Download or read book Quarterly Bulletin of the Canadian Mining Institute written by Canadian Institute of Mining, Metallurgy and Petroleum and published by . This book was released on 2001 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis American Doctoral Dissertations by :
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1998 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Evolution Géodynamique Et Tectonique de la Ceinture de Roches Vertes Paléoprotérozoïque de Sefwi, Craton Ouest-africain (Ghana) by : Helen Mcfarlane
Download or read book Evolution Géodynamique Et Tectonique de la Ceinture de Roches Vertes Paléoprotérozoïque de Sefwi, Craton Ouest-africain (Ghana) written by Helen Mcfarlane and published by . This book was released on 2018 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis investigates the Palaeoproterozoic crust of the West African Craton in southwest Ghana, providing insight into its controversial geodynamic and tectonic evolution. Rocks of the study area comprise greenschist- to amphibolite facies, mafic to felsic volcanic and volcaniclastic rocks, high-grade paragneisses and low-grade volcano-sedimentary packages, all of which are extensively intruded by multiple generations of granitoids. New lithological, metamorphic and structural maps are constructed using integrated field mapping and interpretation of regional airborne geophysical datasets. This approach is used to constrain the deformation history of the sparsely exposed rocks of the NE- to NNE-striking Sefwi Greenstone Belt and the adjacent volcano-sedimentary domains deformed during the Eburnean Orogeny (2150-2070 Ma). Combined geochemical and geochronological analysis of the magmatic suites of the Sefwi Greenstone Belt reveal calc-alkaline, volcanic arc affinities, as well as a striking similarity to Neoarchean TTGs that require diverse magma sources and petrogenetic processes. Rare inherited zircon cores from the Palaeoproterozoic magmatic suite yield ages of ca. 2250 to 2270 Ma, with granitoid emplacement ages ranging between ca. 2189 and 2081 Ma. Zircon Lu-Hf analysis reveals consistently positive eHf(t) values and two-stage crustal model ages between 2650 and 2250 Ma, indicative of a radiogenic proto-crust and short crustal residence times. The magmatic evolution reveals the coeval generation of sodic, high-silica TTGs derived from partial melting of low-K mafic sources and dioritic magmas generated in a metasomatised, LILE-enriched mantle wedge at ca. 2155 Ma. Subsequent emplacement of high-K quartz monzonites at ca. 2136 Ma supports the interaction of mantle-derived magmas and remelting of existing TTGs. The final stage of magmatism is characterised by the emplacement of two-mica-granites and leucogranites along the NW margin of the Sefwi Greenstone Belt between ca. 2092 and 2081 Ma, interpreted as a terminal collisional event during the Eburnean Orogeny. Eburnean metamorphism and deformation is characterised in the study area by initial high-pressure amphibolite facies metamorphism corresponding with low apparent geothermal gradients (HP-MT, ~15-17°C/km). D1 NNW-SSE shortening generated a ubiquitous bedding-parallel foliation (S1) and ~E-W striking thrust faults, resulting in the burial of supracrustal rocks and crustal thickening. In the high-grade terrane, subsequent amphibolite-granulite facies metamorphism is associated with anatexis. In-situ SHRIMP U-Pb monazite ages at ca. 2073 Ma, hosted within, D2 mineral assemblages, are interpreted as the initial timing of cooling and exhumation, significantly later than paroxysmal metamorphism in NW Ghana and central Ivory Coast (2150-2130 Ma). NNE-striking normal detachments and constrictional deformation structures formed during sinistral ENW-WSW transtension (D2), during which segments of the middle- and lower crust were juxtaposed with low-grade domains. Subsequent E-W directed shortening (D3) caused the dextral re- activation of NE-SW striking shear zones, associated with a localised greenschist facies metamorphic overprint. We propose that the juvenile crust of southwest Ghana was generated in an intra-oceanic arc setting, associated with diverse and intense subduction-related magmatism until subsequent terrane accretion and collision. The north-western margin of the Sefwi Greenstone Belt in interpreted as a suture between the separate arc terranes, diachronously accreted during the Eburnean Orogeny. The Palaeoproterozoic crust of the southern portion of the West African Craton represents a juvenile crustal growth event, recording the unique geodynamic and orogenic processes associated with nascent subduction-related plate tectonics in the early Earth.
Book Synopsis Évolution tectono-métamorphique de la continuité lithologique des roches vertes du supérieur dans la zone orogénique de la Province du Grenville by : Éric Ouellet
Download or read book Évolution tectono-métamorphique de la continuité lithologique des roches vertes du supérieur dans la zone orogénique de la Province du Grenville written by Éric Ouellet and published by . This book was released on 1988 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Les ceintures de roches vertes archéennes de Finlande orientale by : Sylvain Blais
Download or read book Les ceintures de roches vertes archéennes de Finlande orientale written by Sylvain Blais and published by . This book was released on 1989 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Le socle de Finlande orientale est composé de trois grands ensembles archéens, caractéristiques des associations "Granites-greenstones" : - des gneiss gris (2,9 à 2,7 Ga) - une ceinture de roches vertes (2,65 Ga) - des granitoides tardifs (2,5 - 2,4 Ga). Ce travail a porté sur l'étude du magmatisme de la ceinture de roches vertes de Kuhmo-Suomussalmi et correspond à un volet d'une démarche visant à reconstituer la genèse et l'évolution de la croûte continentale archéenne. La ceinture de Kuhmo-Suomussalmi est formée par deux grands ensembles magmatiques d'importance volumétrique très inégale : (1) un cycle volcanique inférieur basique et ultrabasique est constitué de deux lignées magmatiques distinctes respectivement de nature komatiitique et tholéiitique ; il se présente sous la forme de coulées à texture spinifex, de cumulats, d'amphibolites, de gabbros, de laves en coussins et de rares formations bréchiques ; (2) un cycle récent, essentiellement tuffacé, est d'extension limitée, chimiquement intermédiaire à acide et de nature calco-alcaline. Parmi les résultats principaux, on peut retenir que : 1) au sein des komatiites, l'étude des caractères texturaux et chimiques des olivines et des clinopyroxènes permet de conclure à leur origine métamorphique. Il est montré de plus, que le développement des minéraux serpentineux s'effectue en trois étapes successives. 2) la dualité komatiite-tholéiite est expliquée par des mécanismes distincts de fusion partielle du manteau archéen. Les taux de fusion élevés donnent des liquides komatiitiques et les taux faibles engendrent les tholéiites. Ces liquides évoluent ensuite par cristallisation fractionnée. 3) la reconstitution géodynamique met en évidence des mécanismes spécifiques à l'Archéen. En effet, sur une croûte continentale gneissique de faible densité se sont épanchées les laves komatiitiques très denses créant ainsi un gradient de densité inverse. Ces laves ont tendance à s'enfoncer dans la croûte, évoluant ainsi par diapirisme inverse ("sagduction"). 4) toutes ces données permettent de déboucher sur une interprétation des relations croûte-manteau à l'Archéen dans le Bouclier baltique
Book Synopsis Masters Abstracts International by :
Download or read book Masters Abstracts International written by and published by . This book was released on 1994 with total page 1192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Evolution tectonique et structurale des Siwalik de l'ouest du Népal by : Laurent Husson
Download or read book Evolution tectonique et structurale des Siwalik de l'ouest du Népal written by Laurent Husson and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis ARCHAEAN CONTINENTAL DEFORMATIONS: NATURAL EXAMPLES AND THERMOMECHANICAL MODELING by : Dominique Chardon
Download or read book ARCHAEAN CONTINENTAL DEFORMATIONS: NATURAL EXAMPLES AND THERMOMECHANICAL MODELING written by Dominique Chardon and published by . This book was released on 1997 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: ln this thesis, we present the results of structural analysis in different segments of Archaean continental crust (>2.5 Ga) in which strain patterns are compatible with the development of crustaI-scale gravity instabilities. We also present analog experiments simulating the development of these gravit y instabilities in order to constrain their thermomechanical significance within the Archaean continental lithosphere. Structural results.A structural study of several greenstone belts from the Dharwar Supergroup (Dharwar craton, India) leads to a progressive deformation model for the initiation of gravity instabilities between the basin and its basement located in the upper structural level of the crust. The basal unconformity of the Dharwar Supergroup acted as a décollement zone. The kinematic criteria within fuis décollement are all compatible with a displacement of the supracrustal rocks toward the internaI parts of the greenstone belts. The décollement-related structures are progressively refolded above the zone of maximum subsidence. ln some of the greenstone belts, the gravity strain pattern interfers with the regional strain field, which is characterized by predominant E-W shortening and N-S trending strike-slip shear zones. ln the Dharwar intracratonic basin, the sagging episode was contemporaneous with the last tectonometamorphic event recognized within the craton, c.a. 2.5 Ga ago. This episode is characterized by the formation of granulites at depth as weIl as by large-scale migmatization associated with the emplacement of a large amount of juvenile materia1. We consider that the high mantle heat flux and partial melting led to the softening of the continental crust and fuis allowed the development of the gravit y instabilities. Within the western Reguibat rise (Mauritania), structural analysis reveals the occurrence of dome-and-basin structures. The strain patterns associated with these structures are interpreted as the result of interference between the diapiric rise of granitoid domes within the greenstone sequences and regional E-W shortening. At the scale of the southern part of the Archaean Reguibat rise, the strain trajectories have the same overall trends in both the high-grade and medium-grade terrains. No major tectonic break has been identified between these metamorphic domains. This implies that the formation of diapiric domes was penecontemporaneous with granulite metamorphism and regional deformation within the lower crust, which occurred c.a.2.7 Ga ago. Experimental results. We used temperature-dependent viscosity material (Gum Rosin) and an new experimental apparatus to simulate unstable granite/greenstone layers. A vertical temperature gradient was maintained, and the deformation was driven by gravit y alone. For a fixed temperature at the bottom of the model, the relative thicknesses of the different layers were changed from one experiment to another. lnsome experiments, a brittle material (sand) was introduced as a superficial layer. The experiments show that : (1) the triggering of gravity instabilities is possible only if the materials at the unstable boundary (cover/basement contact) are ductile and (2) the growth rate of gravity instabilities is an exponential fonction of the temperature at the unstable interface and the temperature gradient at the top of the uns table layer. These results suggest that this type of gravity instability could not develop within a modern continentallithosphere
Book Synopsis Evolution génétique et géodynamique du sillon de roches vertes archéennes de Matagami-Chibougamau dans la partie occidentale du synclinal de Chapais (Abitibi-est, Québec) by : Christian Picard
Download or read book Evolution génétique et géodynamique du sillon de roches vertes archéennes de Matagami-Chibougamau dans la partie occidentale du synclinal de Chapais (Abitibi-est, Québec) written by Christian Picard and published by . This book was released on 1984 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis EVOLUTION STRUCTURALE DU PLATEAU IBLEEN (SICILE, ITALIE) DANS LE CADRE DE L'ARC TYRRHENIEN by : JEAN-LOUP.. MONTENAT
Download or read book EVOLUTION STRUCTURALE DU PLATEAU IBLEEN (SICILE, ITALIE) DANS LE CADRE DE L'ARC TYRRHENIEN written by JEAN-LOUP.. MONTENAT and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: CE TRAVAIL CONCERNE LE PLATEAU IBLEEN (SICILE, ITALIE) QUI PREND PLACE D'AVANT-PAYS STABLE DANS LE CADRE DE L'ARC TYRRHENIEN. L'OBJET DE CETTE ETUDE EST L'ETABLISSEMENT DU CALENDRIER DES DEFORMATIONS AYANT AFFECTE CETTE PLATE-FORME CARBONATEE, DU CRETACE A L'ACTUEL. ON CHERCHE EGALEMENT A DEFINIR LES RELATIONS ENTRE TECTONIQUE ET SEDIMENTATION, EN PARTICULIER POUR L'INTERVALLE OLIGOCENE-PLEISTOCENE DONT LES TERMES SONT LES MIEUX EXPOSES. EN PREMIER LIEU, LA PRESENTATION DES SERIES MESOZOIQUES, POSSIBLE GRACE AUX NOMBREUSES DONNEES DE SUBSURFACE, MET EN LUMIERE LE CONTROLE TECTONIQUE DE LA SEDIMENTATION, ASSURE PAR LES DIRECTIONS STRUCTURALES N-S, NW-SE ET NE-SW. L'ETUDE DETAILLEE DE LA SERIE OLIGO-MIOCENE A PERMIS D'ETABLIR UNE ORGANISATION GEOMETRIQUE DONT LES DIFFERENTS TERMES FORMENT UNE SEQUENCE DE DEPOTS. CELLE-CI EST PRINCIPALEMENT SOUS LE CONTROLE DES VARIATIONS DU NIVEAU MARIN. LES DEFORMATIONS SYNSEDIMENTAIRES NE PERTURBENT QUE LOCALEMENT LES GEOMETRIES. LES DEPOTS PLIO-PLEISTOCENES, AU CONTRAIRE, SONT GOUVERNES ESSENTIELLEMENT PAR LES EVENEMENTS TECTONIQUES ET EN PARTICULIER PAR LES MOUVEMENTS VERTICAUX. AU COURS DE SON HISTOIRE, LE PLATEAU IBLEEN A ETE AFFECTE PAR LE JEU D'ACCIDENTS NE-SW, NW-SE ET N-S, EN GRANDE PARTIE HERITE DES STRUCTURATIONS MESOZOIQUES. L'ETUDE DE CE BATI STRUCTURAL A PERMIS, GRACE A LA CARACTERISATION DE STRUCTURES DATEES, DE RETRACER L'EVOLUTION DES CONTRAINTES DU CRETACE A L'ACTUEL. ON DETERMINE AINSI: UNE EXTENSION NE-SW POUR LE CRETACE, LE PALEOCENE ET L'EOCENE; UNE EXTENSION NW-SE ASSOCIEE A UN RACCOURCISSEMENT NE-SW POUR L'OLIGO-MIOCENE; UN RACCOURCISSEMENT N-S POUR LE PLIOCENE SUPERIEUR; UNE EXTENSION NE-SW ET RACCOURCISSEMENT NW-SE POUR LE PLIOCENE INFERIEUR, LE PLEISTOCENE ET LA PERIODE ACTUELLE. EN RETRACANT L'EVOLUTION STRUCTURALE DU DOMAINE, ON MONTRE QUE L'EXPRESSION DES PROCESSUS TECTONO-SEDIMENTAIRES ESCARPEMENTS, FAILLES SCELLEES, FAILLES HYDROPLASTIQUES, FLEXURATIONS, TRONCATURES, GLISSEMENTS, DEMANTELEMENTS... EST DIRECTEMENT LIEE AU REGIME DE CONTRAINTES EN VIGUEUR, AU JEU DES ACCIDENTS MOBILISES AINSI QU'AUX CONDITIONS DE DEPOT. LA RICHESSE DES ELEMENTS TECTONO-SEDIMENTAIRES A D'AILLEURS PERMIS UNE ETUDE DETAILLEE DE LEUR GEOMETRIE ET DES CONDITIONS DE LEUR MISE EN PLACE. L'EVOLUTION TECTONIQUE ET SEDIMENTAIRE EST ENFIN REPLACEE DANS LE CADRE PLUS REGIONAL DE L'AVANT-PAYS IBLEO-TUNISIEN. CECI NOUS AMENE A PROPOSER UNE EVOLUTION DE L'ARC TYRRHENIEN RENDANT COMPTE DE L'HISTOIRE DU PLATEAU IBLEEN
Book Synopsis Évolution tectonique et géochronologique 40Ar/39Ar de la zone de Humber interne, Appalaches du sud du Québec by : Sébastien Castonguay
Download or read book Évolution tectonique et géochronologique 40Ar/39Ar de la zone de Humber interne, Appalaches du sud du Québec written by Sébastien Castonguay and published by . This book was released on 1999 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'EVOLUTION TECTONIQUE DE LA PARTIE INTERNE DE LA MARGE LAURENTIENNE (ZONE DE HUMBER) DES APPALACHES DU SUD DU QUEBEC RESULTE DE LA SUPERPOSITION DE PLUSIEURS EPISODES TECTONIQUES QUI S'ETENDENT DE L'ORDOVICIEN MOYEN JUSQU'AU DEVONIEN MOYEN. LES OROGENIES TACONIENNE (ORDOVICIEN MOYEN A TARDIF) ET ACADIENNE (DEVONIEN MOYEN A TARDIF) SONT SEPAREES PAR UNE ACTIVITE TECTONIQUE SILURIENNE QUI ETAIT JUSQU'A MAINTENANT INCONNUE. LA PHASE TACONIENNE D 1 - 2 EST RESPONSABLE DE LA MISE EN PLACE DE NAPPES DE CHEVAUCHEMENT VERS L'AVANT-PAYS (NORD-OUEST) DANS LA ZONE DE HUMBER EXTERNE ET DE FAILLES SYN-METAMORPHIQUES DANS LA ZONE INTERNE. LE METAMORPHISME REGIONAL M 1 - 2 EST DU FACIES DES SCHISTES VERTS. LES DONNEES GEOCHRONOLOGIQUES 4 0AR/ 3 9AR SUR MUSCOVITES ET AMPHIBOLES DATENT LE PIC METAMORPHIQUE A 4623 MA. LA PHASE SILURIENNE/DEVONIENNE PRECOCE D 3 EST CARACTERISEE PAR DES STRUCTURES A VERGENCE SUD-EST (ARRIERE-PAYS) ACCOMPAGNEES PAR UN RETROMETAMORPHISME. CETTE TECTONIQUE EST SEPAREE EN STRUCTURES RETROCHEVAUCHANTES, LONGEANT LA FAILLE BENNETT, ET EN EXTENSION LE LONG DE LA FAILLE ST-JOSEPH. DES ANALYSES 4 0AR/ 3 9AR SUR MUSCOVITES, BIOTITES ET AMPHIBOLES PRECISENT L'AGE DE CET EVENEMENT ENTRE 431 ET 411 MA. LES AGES SILURIEN/DEVONIEN PRECOCE PROVIENNENT DU MUR DE LA FAILLE ST-JOSEPH ET SEMBLENT ENREGISTRER LA PROGRESSION D'UNE PHASE DE DEFORMATION DEVELOPPEE DE FACON HETEROGENE. PAR OPPOSITION, LES DONNEES ORDOVICIENNES PROVIENNENT PRESQUE EXCLUSIVEMENT DE ROCHES SITUEES DANS LE TOIT DE LA FAILLE ST-JOSEPH. DEUX MODELES PORTANT SUR LA TECTONIQUE SILURO-DEVONIENNE SONT CONFRONTES. LE PREMIER IMPLIQUE UNE PHASE DE RETROCHEVAUCHEMENT ET D'EXTENSION EN REPONSE A LA CREATION D'UN POINCON TECTONIQUE DE SOCLE GRENVILLIEN. LE DEUXIEME MODELE PRECONISE PLUTOT L'EFFONDREMENT OROGENIQUE ET L'EXHUMATION DE LA ZONE DE HUMBER INTERNE. CE DERNIER MODELE EVOQUE CERTAINES CARACTERISTIQUES, MAIS SURTOUT LA GEOMETRIE D'UN METAMORPHIC CORE COMPLEX.
Book Synopsis Mantle Convection in the Earth and Planets by : Gerald Schubert
Download or read book Mantle Convection in the Earth and Planets written by Gerald Schubert and published by Cambridge University Press. This book was released on 2001 with total page 1016 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive and up-to-date synthesis of all aspects of mantle convection, for advanced students and researchers.
