Recent field surveys in the eastern Hudson Bay region have led to the discovery of regional ice-flow sequences that require a significant reassessment of the late Quaternary dynamics of the Laurentide Ice Sheet. Two regional ice-flow phases can be recognized from till compositional data and from crosscutting relationships observed on striated bedrock surfaces: the oldest is directed toward the northwest and north-northwest, while the youngest is directed toward the west and includes a late-glacial deflection toward the southwest. The wide regional distribution of striae formed during the early northwestward glacial movement together with the recognition of palimpsest glacial dispersal trains associated with this phase suggest that it was a long-lived, time-transgressive regional event. The ensuing glacial movement is a regionally dominant westward ice-flow phase during which several large glacial dispersal trains were formed downglacier from distinctive bedrock sources. The largest of these trains extends westward over a distance of 120 km from Lac à l'Eau Claire to Hudson Bay. Regional glacial transport data as well as glacial and deglacial landforms indicate that this was a long-lived glacial phase, likely lasting throughout the Late Wisconsinan glacial maximum and until déglaciation about 8000 BP. The erosional and depositional record of the northwestward ice-flow event is quite comparable to that of the ensuing glacial phase, and it is thus thought to represent the Early Wisconsinan glacial maximum. In view of the large regional extent of the northwestward ice-flow phase, it must postdate the early buildup of the ice sheet. Along the southeastern Hudson Bay coast, the Late Wisconsinan westward glacial movement was followed by a southwestward deflection that was likely caused by glacial streaming prior to 8000 BP in James Bay, in response to calving and surging into Glacial Lake Ojibway.

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The Annapolis-Cornwallis Valley Aquifer Study was a regional hydrogeological study focusing on major aquifer units of the most important agricultural area of Nova Scotia. The study area covered 2100 km2, and included sedimentary rocks of the Wolfville and Blomidon formations, as well as part of the North and South mountains bordering the valley. The surficial sediment cover is mainly composed of glacial tills, but sand and gravel units are also present in the eastern part of the valley. The main objectives of this project were to improve the general understanding of groundwater flow dynamics and to provide baseline information and tools for a regional groundwater resource assessment. The main bedrock aquifers of the Valley are located in the Wolfville and Blomidon formations, which are composed of lenticular bodies of sandstone, conglomerate, shale and siltstone in variable proportions. The aquifers are often confined and the flow is topographically-driven. Their hydraulic conductivities are in the range of 10-6-10-5 m/s. Good aquifers, though limited in extent, can also be found in the sand and gravel units, with hydraulic conductivities on the order of 10-4 m/s. Groundwater recharge was estimated to range between 115 and 224 mm/a over the entire study area. The vulnerability study showed that bedrock aquifers are typically less vulnerable than surficial aquifers, with the Wolfville Formation being the most vulnerable bedrock formation. Groundwater of the Valley is generally of good quality, although nitrate levels are of concern in several areas.

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