Title | Stratigraphy and lithogeochemistry of the Goldenville horizon and associated rocks, Baie Verte Peninsula, Newfoundland |
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Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
Author | Mueller, C; Piercey, S J ; Babechuk, M G; Copeland, D |
Source | Targeted Geoscience Initiative 5: grant program final reports (2018-2020); by Targeted Geoscience Initiative Coordination Office; Geological Survey of Canada, Open File 8755, 2021 p. 235-249, https://doi.org/10.4095/328990 Open Access |
Year | 2021 |
Publisher | Natural Resources Canada |
Document | open file |
Lang. | English |
Media | on-line; digital |
Related | This publication is contained in Targeted Geoscience
Initiative 5: grant program final reports (2018-2020) |
File format | pdf |
Province | Newfoundland and Labrador |
NTS | 12H/16NE |
Area | Island of Newfoundland; Baie Verte Peninsula |
Lat/Long WENS | -56.1769 -56.0372 49.9992 49.9786 |
Subjects | economic geology; geochemistry; stratigraphy; tectonics; Science and Technology; Nature and Environment; mineral exploration; mineral deposits; gold; sulphide deposits; volcanogenic deposits; ore
mineral genesis; mineralization; ore controls; stratigraphic analyses; lithofacies; lithogeochemistry; magnetite; pyrite; drillholes; bedrock geology; lithology; igneous rocks; volcanic rocks; basalts; lava flows; volcaniclastics; mafic volcanic
rocks; intrusive rocks; gabbros; sedimentary rocks; argillites; cherts; iron formations; ophiolites; tectonic history; magmatism; intrusions; dykes, mafic; hydrothermal systems; fluid dynamics; iron geochemistry; geochemical anomalies; cerium
geochemistry; manganese geochemistry; oxides; depositional environment; sedimentation; detritus; Goldenville Deposit; Snooks Arm Group; Scrape Point Formation; Point Rousse Complex; Mount Misery Formation; Betts Cove Complex; Appalachian Province;
Taconic Seaway; Laurentian Margin; Nugget Pond Deposit; Phanerozoic; Paleozoic; Devonian; Silurian; Ordovician; Cambrian |
Illustrations | geoscientific sketch maps; stratigraphic columns; lithologic logs; geochemical plots; ternary diagrams |
Program | Targeted Geoscience Initiative (TGI-5) Knowledge Management Coordination |
Released | 2021 10 27 |
Abstract | 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. |
Summary | (Plain Language Summary, not published) The Targeted Geoscience Initiative (TGI) is a collaborative federal geoscience program that provides industry with the next generation of geoscience
knowledge and innovative techniques, which will result in more effective targeting of buried mineral deposits. This compendium is the result of the TGI Grant Recipients 2018-2020. |
GEOSCAN ID | 328990 |
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