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

Structural controls on the localization of the mineralized Copper Cliff embayment and the Copper Cliff Offset dyke, Sudbury Igneous Complex, Canada

Mathieu Lucie, Riller Ulrich, Gibson Lisa et Lightfoot Peter C.. (2021). Structural controls on the localization of the mineralized Copper Cliff embayment and the Copper Cliff Offset dyke, Sudbury Igneous Complex, Canada. Ore Geology Reviews, 133, e104071.

[thumbnail of Structural controls on the localization of the mineralized.pdf]
Prévisualisation
PDF - Version acceptée
Disponible sous licence Creative Commons (CC-BY-NC-ND 2.5).

4MB

URL officielle: http://dx.doi.org/doi:10.1016/j.oregeorev.2021.104...

Résumé

The Main Mass of the Sudbury Igneous Complex (SIC) is a 1.5–5 km thick, layered sheet of impact melt rocks, intensely studied because of the magmatic Ni-Cu-PGE sulfide deposits associated with the base of the Main Mass and connected dykes, known as the Sublayer and Offset dykes, respectively. The mode of emplacement of the mineralized Offset dykes that connect to the Main Mass through morphologic crater-floor irregularities (embayments) and the style of post-cratering deformation that affected the Offset dykes is not fully understood. This field-based study of the Copper Cliff Embayment (CCE) and Offset (CCO) dyke contributes to unraveling the mode of melt emplacement and the role of pre-impact faults in the deformation of the southern SIC. Field relationships indicate that the CCO dyke formed before the CCE and Sublayer were chemically fully evolved. Respective melts were injected into footwall rocks weakened by pre-impact deformation and cratering as a protracted event, with barren quartz diorite (QD) emplaced prior to mineralized, inclusion-bearing quartz diorite (IQD). Massive sulfide ore bodies appear to have formed late in the evolution of the dyke and physical separation (decoupling) of silicate magma and sulfide melt is required. NW-SE-shortening folded and faulted the strata hosting the CCO dyke and deformation was facilitated through re-activated E-W-striking, pre-impact faults. Restoring the initial geometry of the dyke and embayment, using 3D modelling and field constraints, helped to refine total slip estimates along major faults and confirmed that melts migrated gravitationally downward into the CCO dyke.

Type de document:Article publié dans une revue avec comité d'évaluation
Volume:133
Pages:e104071
Version évaluée par les pairs:Oui
Date:Juin 2021
Sujets: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:Sudbury Igneous Complex (SIC), Copper Cliff Offset dyke and embayment, magma, fault reactivation, 3D model, structural restoration, Complexe igné de Sudbury (SIC), dyke et baie de compensation de Copper Cliff, réactivation de faille, modèle 3D, restauration structurale
Déposé le:21 juin 2021 14:28
Dernière modification:01 juin 2023 04:00
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