Principal Investigator:
Dr. Réjean Couture

Introduction:

As part of initiatives from the Federal Government of Canada to fill relevant knowledge gaps for hydrocarbon exploration and development in the Mackenzie Valley (Figure 1), the Geological Survey of Canada (GSC), through the Natural Resources Canada’s Secure Canadian Energy Supply Program, initiated a series of research and development (R&D) activities under the umbrella of the Mackenzie Valley project (Manager: Ron DiLabio). Amongst those activities, some are related to landslides and regional hazards along a proposed pipeline in the Mackenzie Valley. These activities include:

• a detailed inventory of landslides and analysis of controlling factors,
• the development of a landslide susceptibility mapping method, and
• the application of remote sensing techniques for landslide mapping and monitoring.

Location:

The study area encompasses a corridor that extends 20 km to either side of the Inuvik-Tulita section of a proposed gas pipeline route, for a distance of 540 km and an area of about 24,000 km² (see dashed line in Figure 2). This Mackenzie Valley Study Area (MVSA) includes the Rampart and the Thunder River regions, both known for widespread landsliding.

Environmental settings:

The study area is characterized by cold winters with low precipitation and mild summers with moderate precipitation (Environment Canada, 2004). The vegetation cover is dominated by coniferous forest (medium to low density) and wetland/shrub land near Inuvik (Cihlar and Beaubien, 1998). The study area is underlain by unconsolidated sediments (99%), which are predominantly by morainal deposits (60%) (Aylsworth et al., 2000), and encompasses three zones of permafrost: continuous (90-100% occurrence), extensive discontinuous (65-90% occurrence), and intermediate discontinuous (35-65% occurrence) (Heginbottom and Radburn, 1992; Figure 1). The permafrost thickness ranges from 0 - 60 m near Norman Wells to 100 - 200 m near Inuvik and the active layer thickness ranges from greater than 1.5 m in Norman Wells to 0.5 m in Inuvik (Wolfe, 1998).