| Titre | Stratigraphy and lithogeochemistry of the Goldenville horizon and associated rocks, Baie Verte Peninsula, Newfoundland |
| Télécharger | Téléchargement (publication entière) |
| |
| Licence | Veuillez noter que la Licence du gouvernement
ouvert - Canada remplace toutes les licences antérieures. |
| Auteur | Mueller, C; Piercey, S J ; Babechuk, M G; Copeland, D |
| Source | Targeted Geoscience Initiative 5: grant program final reports (2018-2020); par Targeted Geoscience Initiative Coordination Office; Commission géologique du Canada, Dossier public 8755, 2021 p. 235-249,
https://doi.org/10.4095/328990  Accès ouvert |
| Année | 2021 |
| Éditeur | Ressources naturelles Canada |
| Document | dossier public |
| Lang. | anglais |
| DOI | https://doi.org/10.4095/328990 |
| Media | en ligne; numérique |
| Référence reliée | Cette publication est contenue dans Targeted
Geoscience Initiative 5: grant program final reports (2018-2020) |
| Formats | pdf |
| Province | Terre-Neuve-et-Labrador |
| SNRC | 12H/16NE |
| Région | Island of Newfoundland; Baie Verte Peninsula |
| Lat/Long OENS | -56.1769 -56.0372 49.9992 49.9786 |
| Sujets | prospection minière; gisements minéraux; or; gîtes sulfureux; gîtes volcanogènes; genèse des minerais; minéralisation; contrôles des minerais; analyses stratigraphiques; lithofaciès; lithogéochimie;
magnetite; pyrite; trous de forage; géologie du substratum rocheux; lithologie; roches ignées; roches volcaniques; basaltes; coulées de lave; volcanoclastique; roches volcaniques mafiques; roches intrusives; gabbros; roches sédimentaires; argilites;
chailles; formations ferrifères; ophiolites; antécédents tectoniques; magmatisme; intrusions; filons mafiques; système hydrothermal; dynamique des fluides; géochimie du fer; anomalies géochimiques; géochimie du cerium; géochimie du manganèse; oxydes;
milieu sédimentaire; sédimentation; débris; Groupe de Snooks Arm ; Formation de Scrape Point ; Complexe de Point Rousse ; Formation de Mount Misery ; Complexe de Betts Cove ; Province Appalachienne; Dépôt de Nugget Pond ; géologie économique;
géochimie; stratigraphie; tectonique; Sciences et technologie; Nature et environnement; Phanérozoïque; Paléozoïque; Dévonien; Silurien; Ordovicien; Cambrien |
| Illustrations | cartes géolscientiques généralisées; échelles stratigraphiques; diagraphies lithologiques; graphiques géochimiques; diagrammes ternaires |
| Programme | Initiative géoscientifique ciblée (IGC-5) Gestion de la connaissance de IGC |
| Diffusé | 2021 10 27 |
| Résumé | (disponible en anglais seulement)
The Goldenville horizon in the Baie Verte Peninsula is an important stratigraphic horizon that hosts primary (Cambrian to Ordovician) exhalative magnetite and
pyrite and was a chemical trap for younger (Silurian to Devonian) orogenic gold mineralization. The horizon is overlain by basaltic flows and volcaniclastic rocks, is intercalated with variably coloured argillites and cherts, and underlain by mafic
volcaniclastic rocks; the entire stratigraphy is cut by younger fine-grained mafic dykes and coarser gabbro. Lithogeochemical signatures of the Goldenville horizon allow it to be divided into high-Fe iron formation (HIF; >50% Fe2O3), low-Fe iron
formation (LIF; 15-50% Fe2O3), and argillite with iron minerals (AIF; <15% Fe2O3). These variably Fe-rich rocks have Fe-Ti-Mn-Al systematics consistent with element derivation from varying mineral contributions from hydrothermal venting and ambient
detrital sedimentation. Post-Archean Australian Shale (PAAS)-normalized rare earth element (REE) signatures for the HIF samples have negative Ce anomalies and patterns similar to modern hydrothermal sediment deposited under oxygenated ocean
conditions. The PAAS-normalized REE signatures of LIF samples have positive Ce anomalies, similar to hydrothermal sediment deposited under anoxic to sub-oxic conditions. The paradoxical Ce behaviour is potentially explained by the Mn geochemistry of
the LIF samples. The LIF have elevated MnO contents (2.0-7.5 weight %), suggesting that Mn from hydrothermal fluids was oxidized in an oxygenated water column during hydrothermal venting, Mn-oxides then scavenged Ce from seawater, and these Mn-oxides
were subsequently deposited in the hydrothermal sediment. The Mn-rich LIF samples with positive Ce anomalies are intercalated with HIF with negative Ce anomalies, both regionally and on a metre scale within drill holes. Thus, the LIF positive Ce
anomaly signature may record extended and particle-specific scavenging rather than sub-oxic/redox-stratified marine conditions. Collectively, results suggest that the Cambro-Ordovician Taconic seaway along the Laurentian margin may have been
completely or near-completely oxygenated at the time of Goldenville horizon deposition. |
| Sommaire | (Résumé en langage clair et simple, non publié)
L'Initiative des géosciences ciblées (IGC) est un programme fédéral collaboratif. Ce programme fournit à l'industrie ce qui est requis pour la
prochaine génération des connaissances géoscientifiques et des techniques novatrices. Le résultat est l'identification des dépôts de minéraux en profondeur. Ce compendium est le résultat des récipiendaires des subventions d'IGC 2018-2020. |
| GEOSCAN ID | 328990 |
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