Till provenance and glacial history of the Petitcodiac (NTS 21 H/14) map area, southeastern New Brunswick

Mapping of surficial deposits and examination of till clast lithologies have contributed to an understanding of the Late Wisconsinan glacial stratigraphy and ice movement in the Petitcodiac map area (NTS 21H/14) of southeastern New Brunswick. Clast and matrix samples were collected from basal till at 2 km intervals across the map area. Ice-flow directions were inferred from the till matrix geochemistry and clast provenance data, as well as from orientation of glacial landforms and striae.; Only a single basal till unit was recognised in the Petitcodiac map area, suggesting that glacial sediments were deposited by a regional ice sheet during the last (Late Wisconsinan) glaciation. The dispersal of till components and the ice-flow data indicate that the dominant ice-flow direction fluctuated between south-southwest and southeast over the entire map area.; In the eastern half of the study area drumlinoid features, rat-tails, striations, geochemical dispersal in the till matrix, and clast dispersal record late easterly and northeasterly ice-flow events. It is likely that ice flow gradually shifted from south-southeast, toward a more easterly direction, as the ice sheet thinned during deglaciation. Eventually the thinning ice sheet became confined by regional topography, and an ice divide developed as ice streamed around the eastern border of the Caledonian Highlands. The ice divide separated ice moving northeastward toward Chignecto Bay, from ice moving southwestward down the Kennebecasis Valley.; Evaluation of the glacial dispersal of till constituents has provided new prospecting targets in the study area. Dispersal of till clasts suggests a local occurrence of unmapped volcanic units, which are often associated with mineralisation in the region. Furthermore, geochemical dispersal indicates that there is potential for local mineralised zones along some faults.