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Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Kamouraska Formation is a quartz-arenitic unit of latest Cambrian - earliest Ordovician age in the Quebec Appalachians that was deposited by hyperconcentrated to concentrated density flows in a meandering submarine canyon on the continental slope bordering the Iapetus Ocean, as outlined in a companion paper. Detailed petrographic study of the quartz arenites of the Kamouraska Formation combined with scanning electron microscopy of grain surface textures suggests that the quartz sands are of eolian origin having been derived from an inland desert or, less likely, a barrier beach dune system. Transport of the mature quartz-arenitic sand onto the shelf and deposition into the deep sea was not accompanied by substantial mixing with material from other sources thus preserving the inherited eolian characteristics. A modern analogue for the eolian interpretation of the deep-sea quartz-arenite beds is as follows: thick, Late Pleistocene eolian sand beds on a modern abyssal plain in the East Atlantic referred to as eolian-sand turbidites that were deposited in the deep sea during glacial sea level lowstands when eolian sand transport to canyon heads was enabled by an exposed and shortened shelf. Similarly, an established sea level lowstand at the Cambro-Ordovician boundary would have facilitated the introduction of eolian sand of the Kamouraska Foundation into canyon heads on the upper slope from where turbidity currents and related density flows were triggered. Correlation of the Kamouraska Formation with the quartz arenites of the Cairnside Formation of Quebec (Keeseville Formation in northern New York State, Nepean Formation in southern Ontario) links the deep-sea deposits with remnants of an inland dune system. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

U-Pb zircon geochronological investigations at Battle Harbour, in the Pinware terrane, eastern Grenville Province show that a cross-bedded psammitic rock from Battle Island was deposited after 1200 Ma and prior to Grenvillian orogenesis, as part of a package of psammitic, semi-pelitic and calc-silicate rocks. This represents a major finding as no previous data had indicated any supracrustal-rock deposition after ca. 1500 Ma in the interior eastern Grenville Province. The age is comparable to that obtained from supracrustal units of minor extent elsewhere in the interior Grenville Province, indicating that change in crustal level in these regions was modest during Grenvillian orogenesis. Grenvillian metamorphism at amphibolite facies occurred at 1030 ±4 Ma, based on evidence from a concordant mafic rock within the supracrustal assemblage that is interpreted to be a sill. Grenvillian orogenesis at Battle Harbour was accompanied by abundant pegmatite injection over an extended period, as indicated by cross-cutting relationships and various states of deformation displayed by the pegmatites. An amazonite-bearing pegmatite has an age of 1024 ±3 Ma. An even younger, cross-cutting pegmatite contains only inherited zircon grains. Des recherches géochronologiques U-Pb sur zircon à Battle Harbour, dans le terrane de Pinware, dans l'est de la Province de Grenville, montrent qu'une roche psammitique de Battle Island a été déposée plus récemment que 1200 Ma et avant l'orogène de Grenville; elle était comprise dans un ensemble de roches psammitiques, semi-pélitiques et calco-silicatées. Ces recherches représentent une découverte importante puisque aucune donnée antérieure n'avait indiqué une déposition d'une roche supracrustale plus récemment que ~1500 Ma à l'intérieur de la Province de Grenville orientale. Cet âge est comparable à ceux obtenus des unités supracrustales de moindre étendue ailleurs à l'intérieur de la Province de Grenville, indiquant que le changement dans le niveau de la croûte de ces régions était modeste durant l'orogène de Grenville. Le métamorphisme grenvillien au faciès des amphibolites a eu lieu à 1030 4 Ma, selon des évidences provenant d'une roche mafique concordante à l'intérieur de l'assemblage supracrustal, laquelle a été interprétée en tant qu'un filon couche. À Battle Harbour, l'orogène de Grenville était accompagné d'une importante injection de pegmatites au cours d'une période prolongée, tel qu'indiqué par les relations d'entrecroisement et les divers niveaux de déformation visibles dans les pegmatites. Une pegmatite contenant de l'amazonite a un âge de 1024 3 Ma. Une pegmatite encore plus jeune qui recoupe en travers ne contient que des grains de zircon hérités. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The intrinsic behaviour of a residual clayey sand derived from sandstone was investigated in one-dimensional compression. The data show some interesting differences when compared with other published data, in that no unique normal compression line can be identified. Although the compressibility on first loading is similar to that for many sandy materials at states on their normal compression lines, the locations of the compression curves were found to be a function of the initial voids ratio, and there was no convergence at higher stresses. Tests on a model clay-sand mixture indicated that this behaviour is common to gap-graded clayey sands.Key words: sands, compressibility, oedometer tests.Le comportement intrinsèque d'un sable argileux résiduel dérivé d'un grès a été étudié en compression unidimensionnelle. Les données montrent des différences intéressantes lorsque comparées avec d'autres données publiées, en ce qu'une ligne de compression normale unique ne peut être identifiée. Quoique la compressibilité durant le premier chargement est similaire à celle de plusieurs matériaux sableux dans des points localisés sur les lignes de compression normale, on a trouvé que les positions des courbes de compression étaient fonction de l'indice de vide initial, et qu'il n'y avait pas de convergence aux contraintes plus élevées. Des essais sur un mélange modèle argile-sable ont indiqué que ce comportement est typique des sables argileux à granulométrie discontinue.Mots clés : sables, compressibilité, essais oedométriques. [Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]