La composition chimique d’une roche magmatique dépend de: . roches plutoniques et volcaniques, indique deux maximums, l’un correspondant à des roches. PREMIÈRE. PARTIE. CHAPITRE I. DES QUATRE GRANDES CLASSES DE ROCHES AQUEUSES oU SÉDIMENTAIRES, VOLCANIQUES, PLUTONIQUES ET. les roches volcaniques et plutoniques pdf. Quote. Postby Just» Tue Aug 28, am. Looking for les roches volcaniques et plutoniques pdf. Will be.
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Pluton emplacement by wall-rock thrusting, hanging-wall translation and extensional collapse: Canadian Mineralogist, 37, riches. In contrast, mid Devonian to early Carboniferous rocks of the Murphy Brook Formation, Fountain Lake Group, and Horton Group show rapid changes in facies and thickness, with common occurrence lfs conglomerate and lacustrine deposits, all suggesting deposition in fault-bound terrestrial basins.
Mylonite and secondary biotite from the Kirkhill fault trend in the Cape Chignecto pluton date from the early Vis. Geochemical evolution of earliest Carboniferous continental tholeiitic basalts along a crustal-scale shear zone, southwestern Maritimes Basin, eastern Canada. Some N—S faults of inferred earliest Carboniferous age appear to terminate against plutons cf.
The — Ma plutons of the Jeffers block are of similar volcabiques to the Debert River granodio-rite. Wilson Brook Formation in the Portapique River area is strongly cleaved and folded, and locally overturned, but much of this deformation is associated with the latest Devonian emplacement of the Pleasant Hills Pluton Pe-Piper et al.
Within the highlands, the Rockland Brook Fault separates two contrasting blocks of Neoproterozoic rocks, the Bass River block plutobiques the south and the Jeffers block to the north Fig. Cependant de telles eorr61ations sont indubitables, d’apr6s rexp6rience des gisements m6tallif res du monde entier.
Late Devonian — earliest Carboniferous basin formation and relationship rocues plutonism, Cobequid Highlands, Nova Scotia. Irregular enclaves and sheets of diabase occur within this fine-grained granite, with textures suggesting that the mafic magma was immiscible cf.
Microtextures des roches magmatiques et métamorphiques
Display large image of Figure 3. Braided fluvial architecture within a rapidly subsiding basin: The Cobequid Fault Fig. No volcanic rocks are known from the Cobequid Highlands of similar age to the Ma Stirling Group of the Mira terrane. We never store sensitive information about our customers in cookies. Display large image of Figure 2 Fig. Much of the granite of the Wentworth pluton within a few kilometres of the Folly Lake gabbro either cross-cuts the gabbro or shows textures indicating the co-existence of immiscible mafic and felsic magmas Pe-Piper et al.
In most of these areas, there is a volcamiques and complex history of Late Neoproterozoic igneous activity. The Wilson Brook Formation passes upwards conformably into the Portapique River Formation, of red unfossiliferous siltstone and minor sandstone, which Donohoe and Wallace interpreted as early Devonian based on lithologic correlation with the Knoydart Formation near Arisaig. This change in paleogeography resulted from the “Acadian orogeny”, but clear volcabiques for “Acadian” deformation is lacking.
Stevens, personal communication, This Neoproterozoic lineament was reactivated in the central Cobequid Highlands, but not in the extreme eastern Cobequid Highlands, where late Paleozoic motion plutonlques taken up on the Cobequid and Millsville faults Fig. The Spicers Cove fault appears to have been important in controlling the location of the poorly exposed Wyvern and Gilbert Mountain plutons Fig. The petrology and geochemistry of iron-oxide deposits within the Cobequid Highlands, Nova Scotia.
Whether this is the result of non-deposition or later erosion is unknown. Fault reactivation within Avalonia: The petrology and geochemistry of the Folly Lake pluton and the contact relationships between the mafic and felsic phases, Cumberland and Colchester counties, Nova Scotia.
A rhyolite flow plutohiques the top of the formation has yielded a U-Pb zircon age of Ma Dunning et al. The granitic rocks have plytoniques high Zr content, similar to distinctive high-Zr rhyolite found only at the extreme top of the Byers Brook Formation Piper et al.
Avalonian terranes or blocks: Geological Survey of Canada Open Filepp. Not included in either block is the Economy River Gneiss, a granodioritic orthogneiss that has yielded a U-Pb zircon age of Ma Doig et al.
However, no suitable detrital sources of pebbles of rhyolite are known in mid Devonian or earlier rocks in this part of the Cobequid Highlands. Late Devonian palinspastic reconstruction of the Avalon-Meguma terrane boundary: The previously reported “West Moose River anorthosite” Pe-Piper and Dessureau consists of rocks trucked from western Newfoundland and dumped in an abandoned gravel pit.
Classification des roches volcaniques The youngest stratified rocks in the Cobequid Highlands comprise fluvial and lacustrine sedimentary rocks of the latest Devonian — Tournaisian Horton Group, which accumulated in fault-bound basins.
Smaller intrusive bodies in this area have been termed the River John gabbro, tonalite and granodiorite units Pe-Piper et al. Sedimentologically, the Murphy Brook Formation resembles the lacustrine facies vilcaniques the Nuttby Formation.
Both formations are known only within the Jeffers Block, but are widely distributed in relatively small inliers from north of Parrsboro in the west to Earltown in the west. Geological Survey of Canada Paper B, pp. The stratigraphy and geochemistry of late Devonian to early Carboniferous volcanic rocks of the northern Chignecto peninsula, Cobequid Highlands, Nova Scotia. In places, the felsic and mafic rocks appear to have been emplaced as co-existing magmas Pe-Piper et al.