The Cold Lake heavy oil field has been studied by geoscientists for more than 30 years and has been producing bitumen for 20 years using the cyclic steam stimulation (CSS) process. Future development options can be improved by the resolution of steam movement and the avoidance of areas of faults and fractures. To locate these features, remote sensing has recently been investigated as a cheaper alternative to four-dimensional seismic surveys.
Advances in satellite and radar technology have made it possible to measure very small movements of the earth's surface found in earthquake zones and volcanic regions. The technique uses synthetic-aperture radar interferometry (InSAR), allowing the measurement of deformation using a vertical resolution, in optimal conditions, on the order of millimeters between repeat acquisitions. This accuracy has only been achieved over dry areas without significant vegetation growth. At the Cold Lake oil field, it has been reported previously that the injection of steam to mobilize the bitumen causes the pump jacks to heave and subside by as much as 30 cm during the first steam cycle. The present project was instigated to determine if such small positive and negative vertical movements could be resolved over the field. Data from three satellite radar sensors were selected: ERS (European remote sensing satellite), JERS (Japanese remote sensing satellite) and Radarsat (the Canadian radar satellite). The present article has provided the first results of repeat-pass InSAR using JERS SAR data for the land subsidence application area. Contrary to the widespread belief that this technology can only be used for dry areas, we show that accurate results, on the order of a centimeter in resolution, can be obtained in a forested area such as Cold Lake using the JERS L-band spaceborne SAR system.