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Direct evidence for an early Neoglacial advance in the Canadian Rocky Mountains is presented. Radiocarbon dates from buried peat and tree remains at Boundary Glacier suggest limiting dates for this advance of between 3800 and 4200 years BP. These data from Boundary Glacier are consistent with previously published dates for the onset of the Neoglacial and an early Neoglacial advance.

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Flood events in the Massawippi drainage basin of southern Quebec are a common phenomenon, usually occurring in the spring months. They are often relatively benign events causing low levels of inconvenience to the local populace, however on occasion fl oods can bring large-scale damage and disruption. Two of the largest fl oods on record for this basin occurred in April 1982 and April 1994. This study examines the meteorological and hydrological conditions present during both months with the goal of identifying any comparable or contrasting features of the fl ood events. The Massawippi drainage basin is one of the largest sub-basins in the Saint-Francois River basin, covering approximately 1670 km 2 . Its relatively large surface area, high frequency of streams, gentle slope and near-circular basin shape combine to create the geomorphological conditions suitable for frequent fl ood events. Abundant winter snowfalls, large spring precipitation events and river ice jams provide the necessary hydrometeorological conditions. In April 1982 a sudden, intense rainstorm created a fl ash fl ood type of situation. Rapidly rising river levels caused some of the worst infrastructure damages ever reported for the Massawippi basin. In contrast the April 1994 fl ood, which reached comparable river discharges, was created through a gradual rise of the basin's rivers by a series of rainstorms and the melting of a deep snowcover over a two-week period. Thus, these two events, although comparable in magnitude, contrasted signifi cantly in their character. The 1982 event, because of the sudden development of its peak fl ow, allowed little time for fl ood preparations and thus caused much more damage than the 1994 event.Résumé : Les épisodes d'inondations dans le bassin versant de la Massawippi dans le sud du Québec sont des phénomènes fréquents qui se produisent habituellement au printemps. Ceux-ci, sont souvent des événements relativement bénins qui causent un faible niveau d'inconvénient à la population locale et pourtant, de temps à autre, ces inondations peuvent être perturbantes et causer une destruction à grande échelle. Deux des plus importantes inondations jamais enregistrées dans ce bassin se sont produites en avril 1982 et avril 1984. Cette recherche, qui examine les conditions météorologiques et hydrologiques présentent lors des deux événements, a pour but d'identifi er toutes les similitudes et dissemblances de ces deux inondations. Couvrant approximativement 1670 km 2 , Le bassin versant de la Massawippi est l'un