LiveZilla Live Chat Software

Constellation, le dépôt institutionnel de l'Université du Québec à Chicoutimi

Deep into the Chibougamau area, Abitibi greenstone belt: Structure of a Neoarchean crust revealed by seismic reflection profiling

Mathieu Lucie, Snyder David, Bedeaux Pierre, Cheraghi Saeid, Lafrance Bruno, Thurston Phil et Sherlock Ross L.. (2020). Deep into the Chibougamau area, Abitibi greenstone belt: Structure of a Neoarchean crust revealed by seismic reflection profiling. Tectonics, 39, (7), e2020TC006223.

Le texte intégral n'est pas disponible pour ce document.

URL officielle: http://dx.doi.org/doi:10.1029/2020TC006223

Résumé

Copper‐gold magmatic‐hydrothermal systems dominate in the Chibougamau area of the Neoarchean Abitibi subprovince (greenstone belt) of the Superior Province (craton), whereas orogenic gold mineralization is more common in the rest of the Abitibi. Understanding differences in metal endowment within the Abitibi greenstone belt requires insights into the geodynamic evolution of the Chibougamau area. This was addressed by imaging the crust using seismic reflection profiling acquired as part of the Metal Earth project. Seismic reflection sections display shallowly south‐dipping reflectors located within the upper crust (e.g., a possible deep continuation of the Barlow fault) and a northward‐dipping midcrust imbricated with older crust (Opatica subprovince) to the north. Multiple reflectors characterize the upper part of the midcrust, interpreted as faults superimposed on a major lithological boundary. These structures likely formed during terrane accretion prior to craton stabilization. Combining the new seismic data with known stratigraphic, structural, and magmatic records, we propose that the study area was initially a normal (i.e., thick) Archean oceanic crust that formed at or before 2.80 Ga and that evolved through terrane imbrication at 2.73–2.70 Ga. Shortening caused rapid burial, devolatilization, and partial melting of hydrated mafic rocks to produce tonalite magmas that may have mixed with mantle‐derived melts to produce the diorite‐tonalite suite associated with observed Cu‐Au magmatic‐hydrothermal mineralization.

Type de document:Article publié dans une revue avec comité d'évaluation
Volume:39
Numéro:7
Pages:e2020TC006223
Version évaluée par les pairs:Oui
Date:26 Juin 2020
Sujets:Sciences naturelles et génie > Génie
Sciences naturelles et génie > Sciences appliquées
Sciences naturelles et génie > Sciences naturelles > Sciences de la terre (géologie, géographie)
Département, module, service et unité de recherche:Départements et modules > Département des sciences appliquées > Unité d'enseignement en sciences de la Terre
Mots-clés:magmatiques-hydrothermaux, Chibougamau, cuivre-or, sous-province néoarchéenne de l'Abitibi, ceinture de roches vertes, minéralisation aurifère orogénique, Metal Earth project, seismic reflection, Chibougamau area, magmatic evolution, geodynamic processes, mineralization
Déposé le:24 févr. 2021 22:14
Dernière modification:24 févr. 2021 22:14
Afficher les statistiques de telechargements

Éditer le document (administrateurs uniquement)

Creative Commons LicenseSauf indication contraire, les documents archivés dans Constellation sont rendus disponibles selon les termes de la licence Creative Commons "Paternité, pas d'utilisation commerciale, pas de modification" 2.5 Canada.

Bibliothèque Paul-Émile-Boulet, UQAC
555, boulevard de l'Université
Chicoutimi (Québec)  CANADA G7H 2B1
418 545-5011, poste 5630