Title | Pinwarian (1.50 Ga) volcanism and hydrothermal activity at the eastern margin of the Wakeham Group, Grenville Province, Quebec |
Author | Corriveau, L; Bonnet, A -L |
Source | The Grenville Province: a geological and mineral resources perspective derived from government and academic research initiatives/La Province de Grenville : l'aspect des ressources géologiques et minérales
découlant des initiatives de recherche gouvernementales et académiques; Canadian Journal of Earth Sciences vol. 42, no. 10, 2005 p. 1749-1782, https://doi.org/10.1139/E05-086 (Open Access) |
Year | 2005 |
Alt Series | Earth Sciences Sector, Contribution Series 2005190 |
Publisher | Canadian Science Publishing |
Document | serial |
Lang. | English |
Media | paper; on-line; digital |
File format | pdf |
Province | Quebec |
NTS | 12K/02; 12K/03; 12K/11 |
Area | Havre Mackenzie; La Romaine; Lac Musquaro; Lac d'Auteuil; Havre Bluff |
Lat/Long WENS | -61.5000 -60.5000 50.7500 50.0000 |
Subjects | igneous and metamorphic petrology; geochemistry; mineralogy; metallic minerals; volcanism; hydrothermal systems; marine environments; hydrothermal alteration; mineralization; metamorphism; continental
margins; volcanoes; volcanic features; magmatism; magmatic arcs; volcanic-sedimentary belts; volcanic exhalitive zone; igneous rocks; volcanic rocks; intrusive rocks; metamorphic rocks; sedimentary rocks; mafic rocks; felsic rocks; silicate rocks;
lavas; pyroclastics; rhyolites; dacites; gneisses; ironstone; carbonate rocks; sillimanite; amphibolites; arenites; basins; metamorphic facies; amphibolite facies; granulite facies; nodules; veins; paragenesis; argillization; textural analyses;
granites; metasedimentary rocks; volcaniclastics; marbles; tuffs; metagabbros; quartzites; arkoses; silicon; aluminum; potassium; sulphides; volcanic bombs; leucosomes; whole rock geochemistry; rock analyses, rare earth elements; geochemical
interpretations; tectonic setting; rock analyses, major elements; rock analyses, trace elements; intrusions; granodiorites; batholiths; mineral potential; sedimentation; sills; plutons; rifts; faults; traps; structural traps; precipitation; base
metals; precious metals; leaching; hematite; magnetite; Grenville Province; Wakeham Group; Laurentia; La Romaine Supracrustal Belt; inhalative material; granitoids; inductively coupled plasma mass spectrometry; inductively coupled plasma atomic
emission spectrometry; high grade metamorphism; chemical traps; Precambrian; Proterozoic |
Illustrations | sketch maps; sketches; stratigraphic columns; photographs; tables; photomicrographs; geochemical plots; ternary diagrams |
Program | Consolidating Canada's Geoscience Knowledge |
Abstract | Volcanic belts developed along the southeastern continental margin of Laurentia between 1.70 and 1.30 Ga and subsequently metamorphosed at high grade are today largely concealed among gneiss complexes
of the Grenville Province. At the eastern end of the Wakeham Group and in the La Romaine Supracrustal Belt to the east, four 1.50 Ga volcanic centres were found among gneissic synvolcanic intrusions typical of the 1.52-1.46 Ga Pinwarian continental
magmatic arc. Upper amphibolite- to granulite-facies rhyolitic to dacitic lavas and coarse lapillistone overlie or are intimately associated with arenites typical of the Wakeham Group. Garnetite, ironstone, carbonate rock, calc-silicate rock, and
sillimanite-bearing nodules, veins, and gneiss, locally preserving lapilli, are also present. The distribution, paragenesis, and modes of most of these latter units differ from those of normal metasediments but are diagnostic of metamorphosed
exhalites and hydrothermal alteration zones. In the La Romaine Supracrustal Belt, they are associated with pyroclastic horizons and a mineralized composite amphibolite unit. Volcanic textures include flow banding, wispy lapilli moulding fragmented
lapilli and rounded lapilli with quartz-feldspar mosaics (filled vesicles), and in situ shattering of lapilli. These textures and the presence of advanced argillic alteration point to vesicular volcanism and hydrothermal activity in a subaerial to
shallow submarine environment. Rare mafic lapilli attest to coeval mafic magmatism. The pervasive calc-alkaline signature of the eruptive and intrusive felsic to mafic rocks and their distribution are compatible with the development of 1.50 Ga
intra-arc volcano-sedimentary belts stemming from the Wakeham Group basin and extending eastward within the Pinwarian continental magmatic arc. |
GEOSCAN ID | 220837 |
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