INSAR Monitoring of the Alaska Pipeline Following the November, 2002 Earthquake Available to Purchase

Repeat pass interferometry using synthetic aperture radar satellites (INSAR) has been used to measure small movements of the earth’s surface associated with both natural and man-made activities. On November 3, 2002, an earthquake measuring 7.9 on the Richter scale struck Alaska along the Denali fault in the vicinity of the Trans-Alaska pipeline crossing. Images from the RADARSAT 1 satellite were acquired both before and after the earthquake and have been analyzed using a variety of techniques, including INSAR, to: • Illustrate various change detection techniques relevant to pipeline structures and natural features of interest (e.g. slopes and glaciers). • Detect and measure subtle earth movement and evaluate the accuracy and operational usefulness by comparing with ground control. The results show increasing land surface deformation near the pipeline crossing at the fault line, and indicate a maximum displacement of 19 feet. Independent ground truth surveys have confirmed the accuracy of these measured displacements. These results demonstrate that radar satellite observations can successfully be used to detect and assess potential threats to the integrity of pipelines. The benefits include: • Accurate measurements of deformation down to the millimeter level. • Remotely monitoring features without extensive groundwork. • Large spatial extent of two-dimensional InSAR monitoring rather than single point monitoring with GPS. • Cost-effective method to observe potential hazards along pipeline right of way. • Ability to “go back in time” for baseline information through the use of archived satellite images.