Geochemical signatures, erratic dispersal, and striae indicate glacial flows in the north-central Gaspé Peninsula exclusively from Appalachian sources, except for the coastal fringe. During the last glacial maximum (LGM), ice from the Monts McGerrigle flowed northward and northwestward over the summits of the eastern Chic-Chocs Range and the coastal plateau to the Gulf of St. Lawrence. Lesser flows also occurred to the north from Mont Albert and the western Chic-Chocs Range. Where intersecting striae were noted, the older flows are associated with a locally developed ice cap. The rare occurrences of striae and erratics, and morphometric and lithological characteristics of summit diamictons, imply limited basal erosion by both local and regional ice caps. This is postulated to result from early protection of rock surfaces by the initial buildup of thin, frozen-based ice in the eastern Chic-Chocs Range. A compact till mantle in the cols and on the coastal plateau and striae parallel to col directions indicate a downslope transition to wet-based ice. Occasional gneiss boulders above the marine limit between Cap-Chat and Sainte-Anne-des-Monts indicate a slight onlap of the Laurentide Ice Sheet (LIS), but the latter was excluded from the interior of the peninsula east of Cap-Chat. Whole-rock geochemistry from three granitoid erratics on Chic-Chocs summits and one in the York River basin indicates a local Devonian rather than a Precambrian Canadian Shield source. The absence of southward downwarping of synchronous postglacial marine limits across the Gaspé Peninsula corroborates this view for the LGM.Résumé : Les signatures géochimiques, la dispersion des blocs erratiques et les stries dans le centre nord de la Péninsule gaspésienne indiquent que l'écoulement glaciaire provenait uniquement de sources appalachiennes, sauf pour la bordure côtière. Durant le dernier maximum glaciaire, la glace des monts McGerrigle s'écoulait vers le nord et le nord-ouest pardessus les sommets de la chaîne orientale des monts Chic-Chocs et le plateau côtier vers le Golfe du Saint-Laurent. Il s'est aussi produit des écoulements secondaires vers le nord, en provenance du Mont Albert et de la chaîne occidentale des monts Chic-Chocs. Là où les stries s'entrecoupent, les plus anciens écoulements sont associés à une calotte glaciaire formée localement. Les rares occurrences de stries et de blocs erratiques ainsi que les caractéristiques morphométriques et lithologiques de diamictons de sommets impliquent une érosion basale par les calottes glaciaires régionales et locales. Cela découlerait de la protection précoce des surfaces rocheuses par l'accumulation de glace mince figée à la base des calottes glaciaires dans la chaîne orientale des monts Chic-Chocs. Un manteau compact de till dans les cols et sur le plateau côtier, avec des stries parallèles aux directions des cols, indique une transition dans le sens de la pente vers de la glace avec présence d'eau à la base. Les blocs occasionnels de gneiss au-dessus de la limite marine, entre Cap-Chat e...
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