Grotz inger, J.P. and Gall, Q., Preliminary investigations of Early Proterozoic Western River and Burnside River formations: ev idence for foredeep or igin of Ki lohigok Basin, District of Mackenz ie; in Curren t Research, Part A, Geological Survey of Canada, Paper 86 -1. A, o. 9 5-106. 1986. - Abstrac tIn the K ilohigok Basin, the Western River and Burnside River formations compr ise three successively overlying tectono-st ratigraphic sedimentary units of regional extent: a basal shallow wa t er siliciclastic/carbonate platform, overlain by deepwater flysch, in turn overlain by shallow marine and fluvial molasse. This stratigraphy represents an initial stable shelf (passive margin?) whose outer, souther ly edge rapidly subsided contemporaneous with arching and subaeria l exposure of its in t erior . Shelf drowning represents the onse t of foredeep subsidence subparallel to the trend of Thelon Tec t onic Zone. Arching and subsidence were perpendicular to the tec tonic transoort direction of intrabasinal nappes. indicating that convergence and upl ift a long Thelon Tec tonic Zone were probably responsible for foredeep subsidence within Ki lohigok Basin.Following drown ing, the p latform was buried by deepwat er deposits (fl ysch); with progressive uplift and basin filling, the foredeep entered the mo lasse phase and fluvial sediments prograded towards the foreland. The foredeep model places constraints on the origin of Thelon Tectonic Zone and pr ovides a more comprehensive understanding of the tectonic evolution of the Slave Province and its r elat ion to the Wopmay Orogen. L'inondation de la plate -forme a marque le debut de l'affa isement de l'avant-fosse subpara lle lement a !'orientation de la zone tectonique de Thelon. Le bombement et l'affa isement ont eu li eu perpendicu lairement a la direction du transport tectonique des nappes intrabassinales, phenomene qui indique que la convergence et le sou levement le long de la zone tectonique de Thelon auraient provoque l'affaisement de l'avant-fosse a l'interieur du bassin de K iloh igok . Apres avoir ete inondee, la plate-forme a ete enfouie sous des sediments d'eau profonde ( flysch) . Le soulevement progressi f e t le comblement du bass in ont marque le debut d'une phase d'accumu lation de molasse dans l'avant-fosse et de progradation des sediments fluviatiles vers !'avant-pays. Ce modele d'avant-fosse apporte ce rtaines restrictions en ce qui a trait a l'origine de la zone tectonique de Thelon et fournit des renseignements plus complets sur !'evolution tectonique de la province des Esclaves e t ses liens avec l'orogene de Wopmay.
In the Deer Lake Basin of western Newfoundland, Canada, analcime has been found within fine‐grained, siliciclastic and carbonate, lake and lake‐margin sediments of the Carboniferous Rocky Brook Formation. Analcime is the only zeolite observed in these unmetamorphosed and non‐volcanogenic rocks. Microscopic analcime occurs as vug‐filling, limpid, isotropic to anisotropic crystals. Microprobe analyses show this type of analcime to be lower in silica than most analcime in sedimentary rocks. A second textural type of finer‐grained submicroscopic analcime can be detected from X‐ray diffraction spectra of Rocky Brook Formation mudstones, where it is associated with phyllosilicates (illite, interstratified chlorite/smectite, smectite, chlorite), other silicates (quartz, feldspar) and carbonates (dolomite, calcite). Results of this study suggest that the analcime in the Rocky Brook Formation formed either by direct lakewater/porewater precipitation or by reaction of these waters with one or more clay mineral types or plagioclase.
In the northwestern part of the Canadian Shield, fluorapatite and a rare-earth element-bearing hydrated aluminum phosphate-sulphate mineral (APS) occur as cements in continental successions near the base of the Paleoproterozoic Thelon Formation (Thelon Basin) and Hornby Bay Group (Hornby Bay Basin). These minerals occupy interstitial sites, form euhedral crystals, display micro-scale zonation, make up part of an unmetamorphosed paragenetic assemblage, and are distributed in correlative units across thousands of square kilometres, suggesting a diagenetic origin. Stratigraphy, geochronology, and other lines of evidence suggest that the Thelon Formation and Hornby Bay Group containing these phosphatic cements, as well as the Ellice Formation and Athabasca Group, are correlative and may have been originally interconnected. The evidence suggests that the basal Thelon Formation and the Hornby Bay Group underwent similar, and approximately coeval, diagenetic mineral paragenesis. Furthermore, the diagenetic fluids in these different locations must have been remarkably similar, especially those that produced the delicate APS mineral. Compared to phosphatic cements in the Hornby Bay and Thelon basins, unmineralized sandstone in the Athabasca Basin contains "crandallite group" and fluorapatite cements higher in the basin fill sequence (Wolverine Point Formation) in tuffaceous sandstone and as relatively early cement in the paragenetic sequence.Résumé : Dans la partie nord-ouest du Bouclier canadien, de la fluorapatite et un minéral hydraté comportant des élé-ments de terres rares, du phosphate et du sulfate d'aluminium (APS), se trouvent en tant que ciments dans des successions continentales à proximité de la base de la Formation de Thelon (bassin de Thelon) et du Groupe de Hornby Bay (bassin de Hornby Bay) tous deux datant du Paléoprotérozoïque. Ces minéraux se trouvent dans les interstices; ils forment des cristaux automorphes, montrent une zonation à très petite échelle, comprennent une partie d'un assemblage paragénétique non métamorphisé et ils sont distribués dans des unités de corrélation sur des milliers de kilomètres carrés, suggérant une origine diagénétique. D'après la stratigraphie, la géochronologie et d'autres observations, la Formation de Thelon et le Groupe de Hornby Bay contenant ces ciments phosphatés, tout comme la Formation d'Ellice et le Groupe d'Athabasca, seraient en corrélation et pourraient avoir été interconnectés à l'origine. Selon les données, la Formation Thelon basale et le Groupe de Hornby Bay auraient subi une paragenèse minérale diagénétique similaire et approximativement contemporaine. De plus, les fluides diagénétiques dans ces différents endroits devaient être remarquablement similaires, surtout ceux qui ont produit le délicat minéral APS. Par rapport aux ciments phosphatiques des bassins de Hornby Bay et de Thelon, un grès non minéralisé dans le bassin de l'Athabasca contient des ciments de fluorapatite et du « groupe de la crandallite » dans une partie supérieure de la séquence de rempl...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.