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Letteratura scientifica selezionata sul tema "Crustal tectonics"

Autore: Grafiati

Pubblicato: 17 marzo 2023

Ultima modifica: 6 settembre 2023

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Articoli di riviste sul tema "Crustal tectonics"

Hawkesworth, Chris J., Peter A. Cawood e Bruno Dhuime. "Tectonics and crustal evolution". GSA Today 26, n. 09 (16 agosto 2016): 4–11. http://dx.doi.org/10.1130/gsatg272a.1.

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Mueller, D. "Plate tectonics and crustal evolution". Eos, Transactions American Geophysical Union 79, n. 18 (1998): 220. http://dx.doi.org/10.1029/98eo00164.

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Horscroft, Timothy J. "Plate tectonics and crustal evolution". Earth-Science Reviews 42, n. 4 (novembre 1997): 276–77. http://dx.doi.org/10.1016/s0012-8252(97)81863-6.

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Clemens, J. D. "Plate tectonics and crustal evolution". Journal of Structural Geology 12, n. 3 (gennaio 1990): 400–401. http://dx.doi.org/10.1016/0191-8141(90)90028-w.

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Fyfe, W. S. "Fluids, tectonics and crustal deformation". Tectonophysics 119, n. 1-4 (ottobre 1985): 29–36. http://dx.doi.org/10.1016/0040-1951(85)90031-9.

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SLEMMONS, D. B. "Crustal Extension: Continental Extensional Tectonics." Science 239, n. 4844 (4 marzo 1988): 1185. http://dx.doi.org/10.1126/science.239.4844.1185.

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Yang-shen, Shi, Yang Shu-feng, Guo Ling-zhi e Dong Huo-gen. "Crustal genesis and plate tectonics". Tectonophysics 187, n. 1-3 (febbraio 1991): 277–84. http://dx.doi.org/10.1016/0040-1951(91)90424-q.

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Singh, Vinod K. "Geology, Geomorphology and Tectonics of India: Introduction". Journal of Geoscience, Engineering, Environment, and Technology 4, n. 2-2 (25 luglio 2019): 1. http://dx.doi.org/10.25299/jgeet.2019.4.2-2.2447.

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Abstract (sommario):

The earth crustal growth since its formation still need in depth research is the conclusion of the three International Conferences on Precambrian Continental Growth and Tectonism, in 2005, 2009 and 2013, organised at the Institute of Earth Sciences of Bundelkhand University, Jhansi, India and its proceedings have valuable source for advance research published the great ideas and achievements from scientists (Chandra et al. 2007; Singh and Chandra, 2011 and Singh et al., 2015). Therefore, this thematic issue planned for consider of crustal growth and tectonic evolution of Indian shield which include 7 research articles on geodynamic evolution of earth, geomorphology, structural, petrologic, isotopic, tectonic, and geochemistry investigations related to the Indian shield and its economic importance (Figure 1).

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Singh, Vinod K., Ram Chandra, Asish R. Basu, Surendra P. Verma e Tapas K. Biswal. "Precambrian crustal growth and tectonics: introduction". International Geology Review 57, n. 11-12 (20 maggio 2015): v—viii. http://dx.doi.org/10.1080/00206814.2015.1029542.

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Nebel, O., F. A. Capitanio, J. F. Moyen, R. F. Weinberg, F. Clos, Y. J. Nebel-Jacobsen e P. A. Cawood. "When crust comes of age: on the chemical evolution of Archaean, felsic continental crust by crustal drip tectonics". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 376, n. 2132 (ottobre 2018): 20180103. http://dx.doi.org/10.1098/rsta.2018.0103.

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The secular evolution of the Earth's crust is marked by a profound change in average crustal chemistry between 3.2 and 2.5 Ga. A key marker for this change is the transition from Archaean sodic granitoid intrusions of the tonalite–trondhjemite–granodiorite (TTG) series to potassic (K) granitic suites, akin (but not identical) to I-type granites that today are associated with subduction zones. It remains poorly constrained as to how and why this change was initiated and if it holds clues about the geodynamic transition from a pre-plate tectonic mode, often referred to as stagnant lid, to mobile plate tectonics. Here, we combine a series of proposed mechanisms for Archaean crustal geodynamics in a single model to explain the observed change in granitoid chemistry. Numeric modelling indicates that upper mantle convection drives crustal flow and subsidence, leading to profound diversity in lithospheric thickness with thin versus thick proto-plates. When convecting asthenospheric mantle interacts with lower lithosphere, scattered crustal drips are created. Under increasing P-T conditions, partial melting of hydrated meta-basalt within these drips produces felsic melts that intrude the overlying crust to form TTG. Dome structures, in which these melts can be preserved, are a positive diapiric expression of these negative drips. Transitional TTG with elevated K mark a second evolutionary stage, and are blends of subsided and remelted older TTG forming K-rich melts and new TTG melts. Ascending TTG-derived melts from asymmetric drips interact with the asthenospheric mantle to form hot, high-Mg sanukitoid. These melts are small in volume, predominantly underplated, and their heat triggered melting of lower crustal successions to form higher-K granites. Importantly, this evolution operates as a disseminated process in space and time over hundreds of millions of years (greater than 200 Ma) in all cratons. This focused ageing of the crust implies that compiled geochemical data can only broadly reflect geodynamic changes on a global or even craton-wide scale. The observed change in crustal chemistry does mark the lead up to but not the initiation of modern-style subduction. This article is part of a discussion meeting issue ‘Earth dynamics and the development of plate tectonics’.

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Tesi sul tema "Crustal tectonics"

Travan, Gaia. "Interactions between salt tectonics and crustal tectonics in the Mediterranean and in the Barents sea". Electronic Thesis or Diss., Université de Lille (2022-....), 2022. http://www.theses.fr/2022ULILR050.

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À l'échelle des temps géologiques, le comportement du sel peut être approché d'un fluide newtonien (comportement visqueux) par rapport au comportement fragile des roches environnantes. La tectonique crustale, extensive et compressive, joue souvent un rôle fondamental dans l'évolution des structures salines et devient la principale cause de déformation dans de nombreuses zones d'étude. Le but de cette thèse est d'analyser le calendrier et les mécanismes de la tectonique salifère dans trois zones d'étude caractérisées par différents âges du sel et l'influence croissante de la tectonique crustale sur la tectonique salifère : la marge sarde occidentale et algérienne septentrionale (Méditerranée occidentale) et le bassin de Sørvestsnaget (mer de Barents sud-ouest). Cela a été fait par l'interprétation de données de réflexion sismique 2D et 3D de TGS (Norvège), OGS (Italie) et UMR Geo-Ocean (France), ainsi que par l'intégration avec d'autres données géophysiques et la comparaison avec des modèles analogiques. Dans la Méditerranée occidentale, le sel déposé pendant la crise de salinité (5,6 Ma) est relativement jeune, la couverture est mince et les marques des premiers stades de déformation sont visibles. Sur la marge sarde occidentale les structures salines sont principalement dues à la pente de la base du sel, résultant de la subsidence différentielle après le remplissage de la Méditerranée à la fin de la crise. En se déplaçant vers le centre du bassin sardo-provençal, où la charge sédimentaire du Rhône Deep Sea Fan forme une lourde couverture au-dessus du sel, l'étalement par gravité domine. Bien que dans cette zone il n'y ait aucune influence de la tectonique crustale sur la déformation du sel à l'échelle régionale, nous avons reconnu sur la marge SW-sarde la présence d'une structure en fleur active pendant le Pliocène. Nous proposons qu'elle fasse partie de la North Balearic Fracture Zone, i.e. la faille de glissement dextre de l'ouverture du bassin sardo-provençal, jamais reconnue dans la région.Le secteur sud de la Méditerranée occidentale est réactivé en compression depuis 8 Ma en raison de la convergence Afrique-Europe, et cette compression s'exprime par des chevauchements sur la marge algérienne. Ici, la tectonique salifère est principalement la conséquence de la tectonique crustale, et en particulier de l'augmentation de l'énergie potentielle résultant de l'élévation localisée. Les modèles analogiques produits montrent que le soulèvement du plateau est à l'origine des variations latérales d'épaisseur de la couche saline et de la formation des minibassins polygonaux dans la zone au large d'Alger. Une composante de glissement par gravité liée à l'affaissement du bassin est présente. La troisième zone d'étude est le bassin de Sørvestsnaget dans la mer de Barents. Ici le sel permien a formé des structures qui sont le résultat de centaines de millions d'années de déformation, principalement par le diapirisme de sel réactif et actif conséquence de la tectonique extensive mésozoïque due à l'ouverture de l'océan Atlantique. Ceci a conduit à la formation de structures de sel allochtones massives et localement à leur déflation. Après la fin de l'extension de la croûte, l'influence principale sur la déformation du sel est attribuable au prisme sédimentaire glaciaire quaternaire et aux mouvements de la croûte contrôlés par glacio-isostasie, ce qui entraîne une redistribution interne dans les structures de sel allochtones comme mis en évidence par la modélisation analogique. Grâce à la diversité géologique entre les trois zones d'étude, nous offrons non seulement une vue d'ensemble des différents niveaux d'interaction entre le sel et la tectonique de la croûte, mais aussi de l'effet de la pente basale du sel et de la charge sédimentaire différentielle sur l'évolution des structures de sel, ainsi que des différents niveaux de maturité des structures de sel, des plus jeunes (par ex. salt rollers) aux plus matures (par ex. salt sheets)
Considering geological times, the behaviour of the salt can be approximated to a Newtonian fluid (i.e. viscous behaviour) compared to the brittle behaviour of the surrounding rocks, and their interaction can be modelled through scaled analogue models of a viscous material and a brittle one, e.g. silicone and sand. Crustal tectonics, both extensional and contractional, have often a fundamental role in the evolution of the salt structures, and becomes the main cause of deformation in many study areas. The aim of this thesis is to analyze the timing and mechanisms of salt tectonics in three study area characterized by different salt ages and increasing influence of crustal tectonics on the salt tectonics processes: the Western Sardinian and Northern Algerian margin (Western Mediterranean) and the Sørvestsnaget Basin (Southwestern Barents Sea). This has been done through the interpretation of 2D and 3D seismic reflection data from TGS (Norway), OGS (Italy) and UMR Geo-Ocean (France), as well as through the integration with other geophysical data, wells data and the comparison with analogue models. In the W-Mediterranean the salt deposited during the Salinity Crisis (5.6 Ma) so salt tectonics is relatively young, the overburden is thin and the marks of the first stages of deformation are usually imaged. On the W-Sardinian margin the salt structures are mainly consequence of the basinward slope of the salt base, resulting from the differential subsidence after the refilling of the Mediterranean at the end of the crisis. Moving towards the center of the Sardo-Provencal basin, where the sedimentary load of the Rhone Deep Sea Fan forms a thick salt overburden, gravity spreading dominates. While in this area there is no influence of crustal tectonics on salt deformation at a regional scale, we recognized on the SW-Sardinian margin the presence of a flower structure active during Pliocene. We propose it to be part of the North Balearic Fracture Zone, i.e. the dextral strike-slip fault of the Sardo-Provençal basin opening, never recognized in the area.The southern sector of the Western Mediterranean is reactivated in compression since 8 Ma due to the Africa-Europe convergence, and this compression is expressed through thrusts on the Algerian margin. Here salt tectonics is mainly the consequence of crustal tectonics, and in particular of the increased potential energy consequence of the localized uplift. The analogue models produced show that the uplift of the plateau is at the origin of the lateral thickness variations in the salt layer and of the polygonal minibasins formation in the area offshore Algiers. A component of gravity gliding related to the basin subsidence is present.The third study area is the Sørvestsnaget Basin in the SW Barents Sea. Here the Permian salt formed structures that are the result of hundreds of millions years of deformation, mainly through reactive and active salt diapirism consequence of the Mesozoic extensional tectonics due to the Atlantic Ocean opening. This lead to the formation of massive allochthonous salt structures and locally to their deflation. After the end of the crustal extension, the main influence on the salt deformation is attributable to the Quaternary glacial sedimentary wedge and the consequent glacio-isostatically controlled crustal movements, leading to internal redistribution in the allochthonous salt structures. Part of the hypothesis on the salt tectonics mechanisms in the Sørvestsnaget basin were confirmed through analogue modelling.Thanks to the diversity between the three study areas in terms of geological setting, we offer not only a broad picture of different levels of interaction between salt and crustal tectonics, but also of the effect of salt basal slope and differential sedimentary load on the salt structures evolution, as well as different levels of maturity of salt structures, from the younger ones (e.g. salt rollers) to the more mature ones (e.g. salt sheets)

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Cragg, Ian Alan. "Numerical modelling of crustal scale fault propagation". Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321166.

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Rayson, Martin W. "Computer aided design of geodetic networks for monitoring crustal tectonics". Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278767.

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Gordon, Andres Cesar. "Arquitetura crustal da bacia de Almada no contexto das bacias da margem lesste da América do Sul". Universidade do Estado do Rio de Janeiro, 2011. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2446.

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A Bacia de Almada, localizada no estado da Bahia, compartilha características similares com as outras bacias da margem leste do Brasil, quando é analisada segundo aspectos como os processos sedimentares e o regime de esforço dominante durante a sua formação. Observa-se uma diferença marcante em relação as outras bacias quando é analisada sob a ótica da composição da crosta transicional, uma vez que não se registra atividade vulcânica durante a fase rifte. A aquisição de um extenso levantamento sísmico 3D, com cabos de 6 km de comprimento e 9.2 segundos de tempo de registro (tempo sísmico duplo), resultaram em imagens sísmicas de boa qualidade das estruturas profundas do rifte. Adicionalmente, estudos de modelagem gravimétrica foram integrados com a análise sísmica para corroborar o modelo geológico. A Bacia de Almada é parte dos sistemas de rifte continentais, desenvolvidos durante o Berriasiano até o Aptiano, que antecederam a quebra do continente do Gondwana, evoluindo posteriormente para uma margem passiva divergente. O processo do rifteamento desenvolveu cinco sub-bacias de orientação NNE-SSO, desde posições terrestres até marinhas profundas, produzindo um arcabouço estrutural complexo. Os perfis da sísmica profunda mostram o afinamento progressivo da crosta continental até espessuras da ordem de 5 km, abaixo da sub-bacia mais oriental, com fatores de estiramento crustal próximo a 7 antes do desenvolvimento de crosta oceânica propriamente dita. As imagens sísmicas de boa qualidade permitem também o reconhecimento de sistemas de falhas lístricas que se iniciam na crosta superior, evoluem atravessando a crosta e conectando as sub-bacias para finalizar em um descolamento horizontal na crosta inferior estratificada. Adicionalmente, a bacia apresenta um perfil assimétrico, compatível com mecanismos de cisalhamento simples. As margens vulcânicas (VM) e não vulcânicas (NVM), são os extremos da análise composicional das margens divergentes continentais. Na Bacia de Almada não se reconhecem os elementos arquiteturais típicos das VM, tais como são as grandes províncias ígneas, caracterizadas por cunhas de refletores que mergulham em direção ao mar e por intenso vulcanismo pré- e sin-rifte nas bacias. Embora a margem divergente do Atlântico Sul seja interpretada tradicionalmente como vulcânica, o segmento do rifte ao sul do Estado da Bahia apresenta características não-vulcânicas, devido à ausência destes elementos arquiteturais e aos resultados obtidos nas perfurações geológicas que eventualmente alcançam a seqüência rifte e embasamento. Regionalmente a margem divergente sul-americana é majoritariamente vulcânica, embora a abundância e a influência do magmatísmo contemporâneo ao rifte seja muito variável. Ao longo da margem continental, desde a Bacia Austral no sul da Argentina, até a Bacia de Pernambuco no nordeste do Brasil, podem ser reconhecidos segmentos de caráter vulcânico forte, médio e não vulcânico. Nos exemplos clássicos de margens não vulcânicas, como a margem da Ibéria, a crosta transicional é altamente afinada podendo apresentar evidências de exumação de manto. Na Bacia de Almada, a crosta transicional apresenta importante estiramento embora não haja evidências concretas de exumação de manto. Os mecanismos responsáveis pela geração e intrusão dos grandes volumes de magma registrados nas margens divergentes são ainda sujeitos a intenso debate. Ao longo da margem divergente sul-americana há evidências da presença dos mecanismos genéticos de estiramento litosférico e impacto de plumas. Alternativamente estes dois mecanismos parecem ter tido um papel importante na evolução tectônica da margem sudeste e sul, diferenciando-as da margem continental onde foi implantada a Bacia de Almada.
The Almada Basin, located in the Bahia State, shares similar characteristics with other eastern Brazilian basins when analyzed in terms of major sedimentation process and dominant stress regime. However, a remarkably different composition of the transitional crust is observed when this basin is compared with the other eastern Brazilian basins. A large 3D survey, acquired with cable length of 6 km and 9.2 seconds resulted in good seismic images of the rift deep structure. A detailed gravity survey and 2D forward modeling were integrated with the seismic analysis to corroborate the geological model. The Almada Basin is part of the continental rift system that developed during the Berriasian to Aptian times, heralding the Gondwana break up. Subsequently the basin evolved into a passive divergent margin. The rifting process results in five NNE-SSW striking half-graben sub-basins, from onshore to deep water, producing a complex structural framework. Deep seismic profiles reveal the progressive thinning of the continental crust down to 5 km below the easternmost half-graben with a crustal β factor of 7 before the ocean crust developed. The good-quality seismic images also allowed the recognition of major listric faults systems that cut the upper crust, linking the half-grabens and detaching along the layered lower crust. The basin shows an asymmetrical crustal profile compatible with a simple shear rifting mechanism. Volcanic Margins (VM) and Non Volcanic Margins (NVM) are the end members of the crustal compositional analysis of divergent continental margins. The key architectural elements of the VM, such as large igneous provinces, seaward dipping reflectors and the basinal synrift magmatism, are not recognized in the Almada Basin. Even though the South Atlantic divergent margin is traditionally interpreted as a VM, particularly in the rift segment south of Bahia State, the lack of these key elements, as well as drilling results, indicate a non volcanic character for the Almada segment. Regionally, the South American divergent margin is mostly volcanic, but the amount and the influence of the magmatism during the rift phase is variable from the southernmost Austral Basin in south Argentina up to the Pernambuco Basin in northeast Brazil. Along the whole continental margin different segments of strong, medium and non volcanic character can be recognized. In the classical NVM, the transitional crust is highly stretched and, in some cases, it shows evidence of exhumed sub continental mantle (e.g., Iberian margin). In the Almada Basin, the transitional crust indicates a considerable thinning, but there is no clear evidence of mantle exhumation. The mechanisms responsible for the generation and emplacement of the large amounts of magma recorded in the divergent margins are still subject to discussions. Along the South American segments, both the lithospheric thinning and mantle plume models have been proposed. Alternatively, a combination of these two mechanisms may have played an important role in the margin evolution.

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Gilbert, John Bennett. "Crustal Deformation During Arc-Flare Up Magmatism: Field And Microstructural Analysis Of A Mid-Crustal, Melt Enhanced Shear Zone". ScholarWorks @ UVM, 2017. http://scholarworks.uvm.edu/graddis/699.

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This study combines structural field data with microstructural observations in an analysis of a mid-crustal shear zone related to the emplacement of the Misty pluton during a high-flux magmatic event in Northern Fiordland, New Zealand. These high-flux magmatic events transport massive amounts of heat and material as they develop along accretionary continental margins, and represent a primary source of continental crust. Fiordland, New Zealand possesses, perhaps, the most extensive middle and lower crustal exposure of these systems on earth. Therefore, this study area provides a significant opportunity to understand processes of continental crust formation in the mid-crust and how these events relate to the broader construction of continents. Herein, I document the four-stage geologic history of the Cozette Burn field area. Pre-existing structures along the Gondwana accretionary margin hosted a regional flare-up magmatic event that produced the Misty pluton and several other large plutons of the West Fiordland Orthogneiss (WFO). This study primarily focuses on the mid-crustal emplacement of the Misty pluton during oblique convergence along the accretionary margin, forming the upper-amphibolite facies Misty Shear Zone (MSZ). The exposures of the MSZ within the Cozette Burn preserve rare structural relationships between host rock and the intrusive Misty pluton. Together, these structures developed during end-stage contractional tectonics that constructed a long-lived (~270+ Ma) composite batholith. Heterogeneous ductile shearing defines the MSZ, with microstructural evidence indicating an interplay of high-temperature crystal plastic deformation along with partial melting of host rock and melt channeling. This resulted in focused, melt-assisted shearing under regional transpressive deformation. These accommodative processes provided an efficient mechanism for moving heat, fluids and magma sourced from the lower crust/mantle boundary into the mid-crust during 15-25 km of crustal thickening related to arc flare-up magmatism. This flare up magmatism and MSZ formation occurred during the final stages of crustal thickening along Gondwana continental margin. High-strain, mylonitic- ultramylonitic shear zones developed in a later phase of deformation, cutting MSZ fabrics near contacts between the Misty pluton and host rock. These more localized shear zones can be attributed to either accommodation of localized melt-pressure buildup or the shift to extensional tectonics. Brittle faulting cut these structures with oblique-thrust in the Tertiary. These mid-crustal structures carry economic relevance: thickened-crust events along accretionary continental margins produce deep-crustal sourced, metal-bearing magmas that are transferred into mid-crust prior to their hydrothermal emplacement as ore deposits in the upper crust. The lasting influence of these processes warrants consideration when assessing continental crust architecture at all scales.

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Chan, Yau-cheong Ian, e 陳有昌. "Characterizing crustal melt episodes in the Himalayan orogen". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206505.

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Extensive studies have been undertaking in exploring the tectonic evolution of the Himalayan Orogen. Various tectonic models were developed to explain and constraint spatially and temporally critical events including the collision of Indian Plate with the Eurasia Plate, crustal thickening in association with the indentation, crustal spreading of the Tibetan Plateau. Recent study by King et al., 2011 identified two distinct leucogranite suites which were formed by contrasting tectonic actions at Sakya. They are Equigranular Anastomosing Leucogranite (AEG) formed under prograde fluidpresent condition while the Discrete Porphyritic Pluton Leucogranite (DPP) formed with retro-grade fluid-absent environment. Based on the characteristics of AEG and DPP, this study started with the acquisition of geochemistry data of rock samples collected for researches at various locations of the Himalaya Orogen. The two leucogranite suites were characterized through the study of their geochemistry comprised major elements, trace elements and rare earth elements models. Results of the studies concluded the existence of AEGs and DPPs distributed over the eastern area of the Himalaya Orogen beyond longitude 85 degree East. DPPs are also found at the far West location of the orogen. AEGs are typically formed from around 38Ma to 23Ma, while DPPs are of young age from 23Ma to 15Ma. Based on the observation of missing, or paucity in data for AEG and DPPs available to the west of longitude 85 degree East, it is hypothesized that recent collision of the Arabia plate to the Iran Domain inhibited the northward indentation movement of the Indian plate that not only caused the anticlockwise rotation of the Indian plate but also decreased the rate of tectonic movement of the Indian plate in the West relative to Eurasia plate. The slow rate of tectonic movement may result in insufficient thickening/energy developed within the crustal layer to cause any melting. Further studies to examine and development of the hypothesis is recommended.
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Lawson, N. Kate. "Crustal accretion near ridge-transform intersections : Kane fracture zone, mid-Atlantic ridge". Thesis, Durham University, 1996. http://etheses.dur.ac.uk/1157/.

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Leftwich, Timothy E. "Geopotential investigations of the crustal structure and evolution of Mars". The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1147893346.

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Dilles, Zoe Y. G. "Geochronologic and Petrologic Context for Deep Crustal Metamorphic Core Complex Development, East Humboldt Range, Nevada". Scholarship @ Claremont, 2016. http://scholarship.claremont.edu/scripps_theses/811.

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The Ruby-Humboldt Range in Northeastern Nevada exposes the deepest crust in the western portion of the Sevier Hinterland. The product of unique brittle and ductile accommodations, this block of lower crustal rock is a window into the processes of continental thickening and extension. The structure of the northern tip of the Ruby-Humboldt Range core complex is dominated by a large recumbent fold nappe with a southward closeure cored by Paleoproterozoic-Archean gneissic complexes with complex interdigitated field relationships that record polyphase continental metamorphism. Amphibolite-grade metapelitic rocks within the core and Winchell Lake nappe record a wide range of zircon age dates of metamorphic events the oldest of which at ~2.5 Ga is recorded in adjacent orthogneiss as a crystallization age. At least two younger metamorphic events are recorded within this orthogneiss, most significantly at 1.7-1.8 Ga, an event previously unpublished for this region that links it to Wyoming province activity in addition to inherited component of detrital cores up to 3.7 Ga in age that is among the oldest ages reported in Nevada. The youngest overprint of cretaceous metamorphic overgrowth ranges fro 60-90 Ma in age based on zircon rims in the aforementioned units as well as three garnet amphibolites that intrude the core of the nappe and are interpreted to be metabasic bodies.

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Wightman, R. T. "Constraints on crustal development and tectonics in the Archaean rocks of south India". Thesis, Open University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374494.

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Libri sul tema "Crustal tectonics"

Condie, Kent C. Plate tectonics & crustal evolution. 3^a ed. Oxford: Pergamon, 1989.

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Plate tectonics & crustal evolution. 3^a ed. Oxford: Pergamon Press, 1989.

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Condie, Kent C. Plate tectonics & crustal evolution. 3^a ed. Oxford: Pergamon Press, 1993.

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C, Condie Kent, a cura di. Plate tectonics and crustal evolution. 4^a ed. Oxford: Butterworth Heinemann, 1997.

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H, Sychanthavong S. P., e Merh S. S, a cura di. Crustal evolution and orogeny. New Delhi: Oxford & IBH Pub. Co., 1990.

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R, Rice J., e United States. National Aeronautics and Space Administration., a cura di. Crustal deformation in great California eartquake cycles. [Washington, DC: National Aeronautics and Space Administration, 1986.

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Parsons, Tom. Crustal structure of the Cascadia fore arc of Washington. Reston, Va: U.S. Geological Survey, 2005.

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E, Smith David, e Turcotte Donald Lawson, a cura di. Contributions of space geodesy to geodynamics: Crustal dynamics. Washington, D.C: American Geophysical Union, 1993.

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Buiter, Susanne J. H. 1970-, Schreurs Guido e Geological Society of London, a cura di. Analogue and numerical modelling of crustal-scale processes. London: Geological Society, 2006.

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United States. National Aeronautics and Space Administration., a cura di. Viscoelastic deformation near active plate boundaries. [Washington, DC: National Aeronautics and Space Administration, 1986.

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Capitoli di libri sul tema "Crustal tectonics"

Muñoz, Josep Anton. "Evolution of a continental collision belt: ECORS-Pyrenees crustal balanced cross-section". In Thrust Tectonics, 235–46. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-3066-0_21.

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Gallagher, John J. "Tectonics of China: Continental Scale Cataclastic Flow". In Mechanical Behavior of Crustal Rocks, 259–73. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm024p0259.

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Pirajno, Franco. "Crustal Evolution, Global Tectonics and Mineral Deposits". In Hydrothermal Mineral Deposits, 159–96. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-75671-9_6.

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Brown, Richard L., Sharon D. Carr, Bradford J. Johnson, Vicki J. Coleman, Frederick A. Cook e John L. Varsek. "The Monashee decollement of the southern Canadian Cordillera: a crustal-scale shear zone linking the Rocky Mountain Foreland belt to lower crust beneath accreted terranes". In Thrust Tectonics, 357–64. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-3066-0_32.

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Bassi, H. G. L. "El Morro: A Tertiary Volcanic Event Controlled by Pre-Paleozoic Crustal Fracturing, San Luis, Argentina". In Basement Tectonics 10, 323–31. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-017-0831-9_30.

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Schwarz, Gerhard, Guillermo Chong Diaz, Detlef Krüger, Eloy Martinez, Winfrid Massow, Volker Rath e José Viramonte. "Crustal High Conductivity Zones in the Southern Central Andes". In Tectonics of the Southern Central Andes, 49–67. Berlin, Heidelberg: Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/978-3-642-77353-2_3.

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Rooney, Sean T., Donald D. Blankenship e Charles R. Bentley. "Seismic Refraction Measurements of Crustal Structure in West Antarctica". In Gondwana Six: Structure, Tectonics, and Geophysics, 1–7. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm040p0001.

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Kahle, Hans-Gert, Max V. Müller, Stephan Mueller, George Veis, Haris Billiris, Demitris Paradissis, Hermann Drewes et al. "Monitoring West Hellenic Arc tectonics and Calabrian Arc tectonics (“WHAT A CAT”) using the Global Positioning System". In Contributions of Space Geodesy to Geodynamics: Crustal Dynamics, 417–29. Washington, D. C.: American Geophysical Union, 1993. http://dx.doi.org/10.1029/gd023p0417.

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Robaudo, Stefano, e Christopher G. A. Harrison. "Plate tectonics from SLR and VLBI global data". In Contributions of Space Geodesy to Geodynamics: Crustal Dynamics, 51–71. Washington, D. C.: American Geophysical Union, 1993. http://dx.doi.org/10.1029/gd023p0051.

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Cook, Frederick A., Dan B. McCullar, Edward R. Decker e Scott B. Smithson. "Crustal Structure and Evolution of the Southern Rio Grande Rift". In Rio Grande Rift: Tectonics and Magmatism, 195–208. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/sp014p0195.

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Atti di convegni sul tema "Crustal tectonics"

Zolnai, G. "Understanding Petroleum Systems in the Light of Crustal Tectonics". In 61st EAGE Conference and Exhibition. European Association of Geoscientists & Engineers, 1999. http://dx.doi.org/10.3997/2214-4609.201407797.

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Lappin, M. "Salt pillows, salt walls and crustal tectonics in the UK Southern Gas Basin". In 55th EAEG Meeting. European Association of Geoscientists & Engineers, 1993. http://dx.doi.org/10.3997/2214-4609.201411699.

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D. Brown, Larry, Andrew Ross e Camelia Diaconescu. "Seismic Bright Spots, Magmatism, Rheology and Moho Tectonics: New Results from Crustal Seismic Profiling". In 5th International Congress of the Brazilian Geophysical Society. European Association of Geoscientists & Engineers, 1997. http://dx.doi.org/10.3997/2214-4609-pdb.299.290.

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DeLucia, Michael S., Mary Seid, Stephen Marshak, Alison Anders, Gary L. Pavlis, Xiaotao Yang, Hersh Gilbert, Chen Chen, Michael W. Hamburger e Timothy Larson. "STRUCTURAL AND GEOMORPHOLOGICAL MANIFESTATIONS OF THE CRUSTAL BOUNDARY BETWEEN THE ILLINOIS BASIN AND OZARK DOME: IMPLICATIONS FOR MIDCONTINENT TECTONICS". In GSA Annual Meeting in Denver, Colorado, USA - 2016. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016am-286885.

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Zhao, Guochun. "DILEMMAS OF PLATE TECTONICS IN EXPLAINING THE NEOARCHEAN CRUSTAL FORMATION AND EVOLUTION OF THE EASTERN BLOCK, NORTH CHINA CRATON". In GSA Annual Meeting in Phoenix, Arizona, USA - 2019. Geological Society of America, 2019. http://dx.doi.org/10.1130/abs/2019am-338062.

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Bennett, Vickie, e Allen Nutman. "The Case for Eoarchean Plate Tectonics and Limited Early Crustal Volumes from Integrated Geologic and Isotopic Observations in Southwest Greenland". In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.168.

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Hasnan, Zurriya Hayati, Amir Ayub, Mohammad Hishamuddin Ismail, Mariah Harris, Soon Mun Chin, Syarifah Nur Syed Khastudin, Nur Yusra Mansor, Tengku Mohd Tengku Hassan, Noor Farahida Ahmad Sharif e Xavier Legrand. "The Black Sea, the Latest New Exploration Frontiers in Europe: Preliminary Results of an Escape Tectonics". In International Petroleum Technology Conference. IPTC, 2021. http://dx.doi.org/10.2523/iptc-21156-ms.

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Abstract OBJECTIVE / SCOPE The Black Sea is a Mesozoic-Cenozoic closed sea system representing one of the last few exploration frontiers in the vicinity of the European market. The overall prospectivity of the basin and associated regional prospective trends have been delineated using the integrated Play-Based Exploration approach. The tectonic evolution, basin formation, sedimentary infilling history, petroleum systems, and sedimentary plays have been investigated to search for new hydrocarbon potential in the basin. METHODS, PROCEDURES, PROCESS The seismic interpretation and mapping were based on 26 sparse 2D seismic lines (ION SPAN), which were acquired and processed in 2011-2012 by ION GTX. The multi-client data from offshore Russia, Crimea, and Ukraine were excluded due to geopolitical sanction. The seismic interpretation which was completed in the depth domain (PSDM depth) was calibrated using three Deep Sea Drilling Project (DSDP) wells namely Sites 379, 380, and 381 (Fig. 1) which penetrated only the shallower section namely the Top Miocene and Top Pliocene. However, the seismic markers where lacking well penetration were primarily interpreted based on seismic stratigraphy. Interpretation of the acoustic basement as well as crustal types were supplemented with gravity and magnetic data from Getech Globe’s database. Three key seismic lines (Fig. 1) were then selected to illustrate the overall basin geomorphology, structural evolution, and to subsequently identify play potential within the basins. The structural analysis was integrated with the seismic sequence stratigraphic analysis to understand the sedimentation history, depositional trends, kinematic evolution, and tectonic history.

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Boavida, J., E. Vagnes, P. Gerónimo, J. M. Peliganga, M. Inkollu, M. de Brito e M. Symonds. "Crustal structure, rift tectonics and pre-salt stratigraphy beneath the Ultra Deep Water area offshore Angola: Results from reprocessed seismic data". In 7th SAGA Biennial Technical Meeting and Exhibition. European Association of Geoscientists & Engineers, 2001. http://dx.doi.org/10.3997/2214-4609-pdb.143.16.2.

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Bethune, Kathryn, Kenneth Ashton, Colin Card, Michael Cloutier e Jordan Deane. "TECTONICS OF WSW RAE CRATON OF LAURENTIA; EVIDENCE FOR CRUSTAL ASSEMBLY BY COLLISIONAL, ACCRETIONARY PROCESSES FROM THE MID-NEOARCHEAN TO EARLY PALEOPROTEROZOIC". In GSA 2020 Connects Online. Geological Society of America, 2020. http://dx.doi.org/10.1130/abs/2020am-358460.

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van Rooyen, Deanne, e David Corrigan. "PLATE TECTONICS DURING THE 1.9 – 1.7 GA ASSEMBLY OF NUNA; EXAMPLES OF MODERN CRUSTAL COLLISION AND TRANSPORT PROCESSES FROM THE SOUTHEASTERN CHURCHILL PROVINCE". In GSA 2020 Connects Online. Geological Society of America, 2020. http://dx.doi.org/10.1130/abs/2020am-353342.

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Rapporti di organizzazioni sul tema "Crustal tectonics"

Sweeney, J. F., R. A. Stephenson, R. G. Currie e J. M. Delaurier. Crustal Geophysics [Chapter 2: Tectonic Framework]. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1991. http://dx.doi.org/10.4095/134077.

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Matte, S., M. Constantin e R. Stevenson. Mineralogical and geochemical characterisation of the Kipawa syenite complex, Quebec: implications for rare-earth element deposits. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329212.

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The Kipawa rare-earth element (REE) deposit is located in the Parautochton zone of the Grenville Province 55 km south of the boundary with the Superior Province. The deposit is part of the Kipawa syenite complex of peralkaline syenites, gneisses, and amphibolites that are intercalated with calc-silicate rocks and marbles overlain by a peralkaline gneissic granite. The REE deposit is principally composed of eudialyte, mosandrite and britholite, and less abundant minerals such as xenotime, monazite or euxenite. The Kipawa Complex outcrops as a series of thin, folded sheet imbricates located between regional metasediments, suggesting a regional tectonic control. Several hypotheses for the origin of the complex have been suggested: crustal contamination of mantle-derived magmas, crustal melting, fluid alteration, metamorphism, and hydrothermal activity. Our objective is to characterize the mineralogical, geochemical, and isotopic composition of the Kipawa complex in order to improve our understanding of the formation and the post-formation processes, and the age of the complex. The complex has been deformed and metamorphosed with evidence of melting-recrystallization textures among REE and Zr rich magmatic and post magmatic minerals. Major and trace element geochemistry obtained by ICP-MS suggest that syenites, granites and monzonite of the complex have within-plate A2 type anorogenic signatures, and our analyses indicate a strong crustal signature based on TIMS whole rock Nd isotopes. We have analyzed zircon grains by SEM, EPMA, ICP-MS and MC-ICP-MS coupled with laser ablation (Lu-Hf). Initial isotopic results also support a strong crustal signature. Taken together, these results suggest that alkaline magmas of the Kipawa complex/deposit could have formed by partial melting of the mantle followed by strong crustal contamination or by melting of metasomatized continental crust. These processes and origins strongly differ compare to most alkaline complexes in the world. Additional TIMS and LA-MC-ICP-MS analyses are planned to investigate whether all lithologies share the same strong crustal signature.

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Hayward, N., e S. Paradis. Geophysical reassessment of the role of ancient lineaments on the development of the western margin of Laurentia and its sediment-hosted Zn-Pb deposits, Yukon and Northwest Territories. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330038.

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The role of crustal lineaments in the development of the western margin of Laurentia, Selwyn basin and associated sediment-hosted Zn-Pb deposits (clastic-dominated, Mississippi-Valley-type) in Yukon and NWT, are reassessed through a new 3-D inversion strategy applied to new compilations of gravity and magnetic data. Regionally continuous, broadly NE-trending crustal lineaments including the Liard line, Fort Norman structure, and Leith Ridge fault, were interpreted as having had long-standing influence on craton, margin, and sedimentary basin development. However, multiple tectonic overprints including terrane accretion, thrust faulting, and plutonism obscure the region's history. The Liard line, related to a transfer fault that bounds the Macdonald Platform promontory, is refined from the integration of the new geophysical models with published geological data. The geophysical models support the continuity of the Fort Norman structure below the Selwyn basin, but the presence of Leith Ridge fault is not supported in this area. The ENE-trending Mackenzie River lineament, traced from the Misty Creek Embayment to Great Bear Lake, is interpreted to mark the southern edge of a cratonic promontory. The North American craton is bounded by a NW-trending lineament interpreted as a crustal manifestation of lithospheric thinning of the Laurentian margin, as echoed by a change in the depth of the lithosphere-asthenosphere boundary. The structure is straddled by Mississippi Valley-type Zn-Pb occurrences, following their palinspastic restoration, and also defines the eastern limit of mid-Late Cretaceous granitic intrusions. Another NW-trending lineament, interpreted to be associated with a shallowing of lower crustal rocks, is coincident with clastic-dominated Zn-Pb occurrences.

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Zagorevski, A., C. R. van Staal, J. H. Bédard, A. Bogatu, D. Canil, M. Coleman, M. Golding et al. Overview of Cordilleran oceanic terranes and their significance for the tectonic evolution of the northern Cordillera. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/326053.

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Ophiolite complexes are an important component of oceanic terranes in the northern Cordillera and constitute a significant amount of juvenile crust added to the Mesozoic Laurentian continental margin during Cordilleran orogenesis. Despite their tectonic importance, few systematic studies of these complexes have been conducted. Detailed studies of the pseudostratigraphy, age, geochemistry, and structural setting of ophiolitic rocks in the northern Cordillera indicate that ophiolites formed in Permian to Middle Triassic suprasubduction zone settings and were obducted onto passive margin sequences. Re-evaluation of ophiolite complexes highlights fundamental gaps in the understanding of the tectonic framework of the northern Cordillera. The previous inclusion of ophiolite complexes into generic 'oceanic' terranes resulted in significant challenges for stratigraphic nomenclature, led to incorrect terrane definitions, and resulted in flawed tectonic reconstructions.

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Heather, K. B., J. A. Percival, D. Moser e W. Bleeker. Tectonics and metallogeny of Archean crust in the Abitibi-Kapuskasing-Wawa region. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1995. http://dx.doi.org/10.4095/205285.

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Hayward, N., e J. J. Ryan. Geophysical characteristics of the northern Cordillera. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/326069.

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Geophysical data acquired under the Geological Survey of Canada's GEM Cordillera project provide a foundation to a broad range of geological investigations in the northern Canadian Cordillera. For areas of specific geological interest, over 230 000 km of high-resolution aeromagnetic data form a mosaic of comprehensive coverage over a total area of more than 82 000 km2. The data provide a powerful and valuable legacy data set for current and future activities by the Geological Survey of Canada and academic and industry partners and clients. Foremost, geophysical data interpretation complements surface geological mapping, especially in inaccessible terrain where bedrock exposure is commonly poor, enabling clearer definition of a region's geology and structure. Beyond applications to bedrock geological mapping, geophysical modelling, integrated with geological results, affords an improved understanding of the deeper crustal structure, leading to new models of the region's tectonic development and mineral deposit context.

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Keen, C. E., K. Dickie, L. T. Dafoe, T. Funck, J. K. Welford, S A Dehler, U. Gregersen e K J DesRoches. Rifting and evolution of the Labrador-Baffin Seaway. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/321854.

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The evolution of the 2000 km long Mesozoic rift system underlying the Labrador-Baffin Seaway is described, with emphasis on results from geophysical data sets, which provide the timing, sediment thickness, and crustal structure of the system. The data sets include seismic reflection and refraction, gravity, and magnetic data, with additional constraints provided by near-surface geology and well data. Many features that characterize rift systems globally are displayed, including: wide and narrow rift zones; magma-rich and magma-poor margin segments; exhumation of continental mantle in distal, magma-poor zones; and occurrences of thick basalts, associated with the development of seaward-dipping reflectors, and magmatic underplating. The magma-rich regions were affected by Paleogene volcanism, perhaps associated with a hotspot or plume. Plate reconstructions help elucidate the plate tectonic history and modes of rifting in the region; however, many questions remain unanswered with respect to this rift system.

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St-Onge, M. R., e S. B. Lucas. New insight on the crustal struture and tectonic history of the Ungava Orogen, Kovik Bay and Cap Wolstenholme, Québec. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1992. http://dx.doi.org/10.4095/132846.

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Karson, Jeffrey A. Variations in Tectonic Extension Along SLow-Spreading Ridge Axes: Implications for the Internal Structure and Bathymetry of Oceanic Crust. Fort Belvoir, VA: Defense Technical Information Center, gennaio 1992. http://dx.doi.org/10.21236/ada244583.

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Kuster, K., C. M. Lesher e M. G. Houlé. Geology and geochemistry of mafic and ultramafic bodies in the Shebandowan mine area, Wawa-Abitibi terrane: implications for Ni-Cu-(PGE) and Cr-(PGE) mineralization, Ontario and Quebec. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329394.

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The Shebandowan Ni-Cu-(PGE) deposit occurs in the Shebandowan greenstone belt in the Wawa-Abitibi terrane. This deposit is one of a few economic Ni-Cu-(PGE) deposits in the Superior Province and one of a very few deposits worldwide that contains both Ni-Cu-(PGE) and Cr-(PGE) mineralization. The mafic-ultramafic successions in the area comprise abundant flows and sills of tholeiitic basalt and lesser Al-undepleted komatiite (MgO &gt;18 wt%, Al2O3/TiO2 = 15-25), the latter indicating separation from mantle sources at shallow levels. Siliceous high-Mg basalts (MgO 8-12 wt%, SiO2 &gt; 53 wt%, TiO2 &lt; 1.2 wt%, La/Sm[MN] &lt; 1-2) are relatively abundant in the area and likely represent crustally contaminated komatiites. Ultramafic bodies in the Shebandowan mine area comprise at least three or four komatiitic sills (A-B, C, D) and at least two komatiitic flows (E, F), all of which are altered to serpentinites or talc-carbonate schists with relict igneous chromite and rare relict igneous orthopyroxene-clinopyroxene. Unit A-B contains pentlandite-pyrrhotite-chalcopyrite-pyrite-magnetite mineralization, occurring as massive sulfides, sulfide breccias, or stringers, and subeconomic chromite mineralization in contorted massive bands varying from a few millimetres up to 10 metres thick. The localization of massive and semi-massive Ni-Cu-(PGE) ores along the margins of Unit A and the paucity of disseminated and net-textured ores suggest tectonic mobilization. Chromite is typically zoned with Cr-Mg-Al-rich (chromite) cores and Fe-rich (ferrichromite/magnetite) rims due to alteration and/or metamorphism, but rarely contains amoeboid magnetite cores. The thickness of chromite in Unit B is too great to have crystallized in cotectic proportion from the komatiitic magma and a model involving dynamic upgrading of magnetite xenoliths derived from interflow oxide facies iron formations is being tested.

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