In an initial review of sediment thickness data by the Alberta Geological Survey, as part of work under the Mackenzie River Basin Bilateral Water Management Agreement between the governments of the Northwest Territories and Alberta, conflicting models of sediment thickness along the provincial/territorial border (lat. 60°N) were identified. This report summarizes work undertaken to resolve this boundary issue. For this study, all available point source data of sediment thickness were re-examined and then used to remodel the bedrock topography and sediment thickness. Oil and gas well drill cuttings and water well records demonstrate that most of the Cameron Hills Uplands in northwestern Alberta and southern Northwest Territories are composed of thick (250–400 m) unconsolidated sediments. Within Alberta, these sediments overlie a possible valley, oriented northwest. Comparatively thin sediment (0–15 m) is modelled for the Hay River area (long. 116°00′W to 117°30′W) and the Great Slave Plain area (long. 112°30′W to 116°00′W). Drill cuttings from the thick sediment package on the Cameron Hills Uplands include granitic and other Canadian Shield rock fragments that indicate glacial transport by a continental (Laurentide) ice sheet in the region.

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Utting, D.J., Smith, I.R., Pawley, S.M. and Deblonde, C. (2023): Updated bedrock topography and sediment thickness models to support aquifer mapping in the Alberta–Northwest Territories transboundary region; Alberta Energy Regulator / Alberta Geological Survey, AER/AGS Open File Report 2023-01, 51 p.