Abstrakt: |
Abstract: Withdrawal of natural gas is being planned in the area of lower Mackenzie River Delta in northern Canada. The subsidence caused by the gas withdrawal is predicted to reach about 0.5 m within the next 25-30 years. Due to the low laying land, the ground subsidence may result in hydrological changes and flooding of large areas that is of a major concern to environmental protection. A monitoring scheme is being designed to verify the prediction models. One of the important tasks of the monitoring scheme will be to separate ground subsidence due to gas withdrawal from the total surface deformation resulting from natural causes such as permafrost degradation and post-glacial isostatic or tectonic uplift/subsidsence of the area. Global Positioning System (GPS) and satellite Interferometric Synthetic Aperture Radar (InSAR) are being considered as the main tools of monitoring. |