In continuous permafrost regions, taliks (areas of unfrozen ground) occur mainly beneath large and deep lakes (> 2 m depth) that do not freeze to their bottom. Open taliks connected to regional groundwater can affect the development of mine projects by providing pathways for mine water inflow or contaminant transport. It is therefore important to determine which lakes are potentially underlain by open taliks. A methodology is presented to assess the potential for talik occurrence at a regional scale. The methodology considers lake geometry, lake terrace width, surrounding landscape topography, ground thermal conditions and lake water temperature. Lakes are classified as circular or elongated using GIS analysis. High resolution imagery is used to classify the center pool and the average terrace width of each lake. The ArcticDEM is used to extract topographical variables surrounding lakes to run predictive models of maximum lake depth and to determine if the center pool of each lake is shallow (< 4 m) or deep (³ 4 m) to subsequently attribute a lake water temperature. Lake temperature values for central pools and terraces and the geothermal gradient and ground surface temperature are based on literature values from reports submitted for Environmental Impact Assessments. All parameters are combined in equations defined for circular or elongated lakes in a semi-infinite horizontal plane, with the assumption of steady-state conditions. Ranges of values for lake terrace and ground surface temperatures and geothermal gradient are introduced in equations to cope with uncertainty. This allows classification of each lake as “no open talik”, “potential open talik”, and “open talik”. The methodology is validated with known maximum lake depths, bathymetric contours, and confirmed occurrence of open taliks. Results for mineral resource development areas in Nunavut are provided.