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Presents a reply to a comment on the study "Analysis and Reinterpretation of Deformation Features in the Rouge River Valley, Scarborough, Ontario," by N. Eyles and A. Mohajer. Structural analysis of deformation features in relation to local ice flow directions; Interpretation of drumilinoid features; Compatibility of the faults with neotectonic-related or glacial tectonic-related processes.

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 Cariboo Mountains, British Columbia, contain an intracontinental dextral strike-slip fault system that crosscuts the regional fold structures. This fault system accounts for a minimum of 120 km and a maximum of 200 km of dextral strike-slip displacement. This probably accommodates some of the motion associated with the southern termination of the Northern Rocky Mountain Trench Fault and is part of a step-over zone between the Northern Rocky Mountain Trench Fault and the Fraser River – Straight Creek fault systems. The Isaac Lake Synclinorium is a kilometre-scale Jurassic fold structure that is bounded by the dextral oblique Isaac Lake and Winder strike-slip faults. These faults are part of the regional strike-slip fault system that is found throughout the Cariboo Mountains. Deformation associated with the strike-slip faults is complex and is partitioned into motion along the faults and into the formation of kilometre-scale folds that are found in areas between the faults. The angular relationship between the strike-slip faults and folds conforms to models developed for dextral strike-slip fault systems with drag on high-friction faults. We interpreted these structures to have formed during a continuous deformation event. Timing constraints indicate that faulting started by the Late Cretaceous and may have had a long and protracted history into the Tertiary.La chaîne Cariboo, en Colombie-Britannique, possède un système intracontinental de failles décrochantes dextres qui recoupe les structures de pli régionales. Ce système de failles est responsable d'un déplacement horizontal dextre d'au moins 120 km et d'au plus 200 km. Il est aussi probablement responsable d'une partie du mouvement associé à l'extrémité sud de la faille du sillon des Rocheuses septentrionales et il fait partie de la zone empiétant sur la faille du sillon des Rocheuses septentrionales et les systèmes de failles Fraser River – Straight Creek. Le synclinorium de Isaac Lake est une structure de pli d'ordre kilométrique, datant du Jurassique; il est limité par les failles décrochantes dextres obliques de Isaac Lake et de Winder. Ces failles font partie du système de failles décrochantes régionales que l'on retrouve à travers toute la chaîne Cariboo. La déformation associée aux failles décrochantes est complexe et elle est répartie en mouvement le long des failles et en formation de plis d'échelle kilométrique qui se retrouvent dans certaines régions entre les failles. La relation angulaire entre les failles décrochantes et les plis est conforme aux modèles développés pour des systèmes de failles décrochantes dextres comportant du frottement pour les failles à coefficient de frottement élevé. Nous croyons que ces structures ont été formées au cours d'un événement de déformation continue. Les contraintes de temps indiquent que les failles ont débuté au Crétacé tardif et qu'elles ont pu avoir une longue histoire qui s'est prolongée jusqu'au Tertiaire.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Structural information about that portion of the economically important Destor–Porcupine Deformation Zone and its associated faults, which lie buried under many metres of Clay Belt sediments in the region north of Matheson, Ontario, must rely principally on interpretation of geophysical data. In this area, the Archean greenstones of the Abitibi are crosscut by at least three generations of strongly magnetic diabase dykes. The predominant dyke set, the Matachewan, trend north–south, orthogonal to structures in the greenstones. Directional horizontal derivative analysis of the total magnetic field, which has a much sharper angular cutoff than that provided by standard Fourier-based filters, provides a method for separating the magnetic contributions from these two sources. This analysis revealed the existence of a previously unidentified fault (the Winslow fault) located to the north of, and parallel to, the economically significant Pipestone Fault. We also define a second new fault, the Carr fault, that is intimately associated with the existence of a buried felsic intrusive complex in Carr Township. Possible associations between these faults and previously known faults defined from surface mapping programs are explored.On doit se fier surtout à des interprétations de données géophysiques pour obtenir des informations structurales sur la portion d'importance économique de la Zone de déformation Destor–Porcupine et ses failles associées qui se trouvent enfouies sous plusieurs mètres de sédiments du Clay Belt dans la région au nord de Matheson, en Ontario. Dans cette région, les roches vertes archéennes de l'Abitibi sont recoupées par au moins trois générations de dykes de diabase fortement magnétiques. L'ensemble de dykes prédominant, le Matachewan, a une direction N–S orthogonale aux structures dans les roches vertes. L'analyse directionnelle de la dérive horizontale du champ magnétique total, qui a une coupure angulaire beaucoup plus abrupte que celle des filtres standard basés sur les séries de Fourier, fournit une méthode pour séparer les contributions magnétiques de ces deux sources. Cette analyse révèle l'existence d'une faille antérieurement non identifiée (la faille Winslow) située au nord de, et parallèle à, la faille Pipestone, une faille d'une grande importance économique. Nous définissons également une seconde nouvelle faille, la faille Carr, qui est intimement associée à l'existence d'un complexe intrusif felsique enfoui dans le canton de Carr. Nous étudions aussi les associations possibles entre ces failles et d'autres failles connues antérieurement alors que définies par des programmes de cartographie de surface.[Traduit par la Rédaction] [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.)

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.)

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.)

Application of bandpass and directional filtering to potential-field data in northwestern Canada allows separation of anomalies due to northwest-oriented upper crustal sources that are associated with Cordilleran structures from anomalies due to northeast-oriented lower crustal sources that are primarily associated with Precambrian Shield rocks. In northeastern British Columbia, northeast-trending lower crustal structures of the Canadian Shield as represented in the gravity patterns appear to project west of the Tintina fault – Northern Rocky Mountain Trench at about 56°N. About 400–500 km farther north, the Tintina fault may penetrate into the lithospheric mantle. It is, thus, likely that the depth extent of the Tintina fault rises southward into the crust, as dextral strike-slip motion is transformed into contractional structures of the southern Cordillera.L'application de filtres directionnels à bandes passantes sur des données de champ potentiel dans le Nord-ouest canadien permet de séparer les anomalies dues à des sources de la croûte supérieure orientées vers le nord-ouest (qui sont associées aux structures de la Cordillère) des anomalies causées par des sources de la croûte inférieure orientées vers le nord-est (qui sont surtout associées à des roches du Bouclier précambrien). Dans le Nord-ouest de la Colombie-Britannique, les structures à direction nord-est de la croûte inférieure du Bouclier, telles que représentées dans les patrons de gravité, semblent se projeter à l'ouest de la faille Tintina – sillon des Rocheuses septentrional à environ 56ºN. Environ 400–500 km plus au nord, la faille Tintina pourrait pénétrer dans le manteau lithosphérique. Il est donc probable que la profondeur de la faille Tintina s'élève vers le sud à l'intérieur de la croûte alors que le décrochement dextre est transformé en structures de contraction de la Cordillère méridionale.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]