INSAR ANALYSIS OF THE ABSHERON PENINSULA AND NEARBY AREAS, AZERBAIJAN

摘要

A set of Synthetic Aperture Radar (SAR) data covering the Absheron Peninsula is processed using interferometic synthetic aperture radar (InSAR) to generate a detailed digital elevation map of the region and to measure possible surface deformations. The dataset includes eight ERS-1 and ERS-2 scenes from 1996 though 1999 and images Radarsat images from 1999. The radar has a wavelength of 5.66 cm allowing theoretical resolution along the line of sight to the satellite of surface deformations on the order of mm. Possible causes of surface deformation are earthquakes, mud volcanism, groundwater changes, and hydrocarbon withdrawal. We also use optical satellite images (Advanced Spaceborne Thermal Emission and Reflection - ASTER) and ground truth data. Initial In-SAR processing used a digital elevation model (DEM) based on the combination of a global DEM with a high resolution DEM derived from ASTER stereo optical data. This DEM was then refined with radar pairs possessing short temporal baselines. Correlation over the area was fair with moderate to low correlation over a time period of 2 years. Preliminary results show no clear indications (> 10 cm line-of-sight) of large deformation over known mud volcanoes during the periods spanned by the interferograms. Preliminary modeling of likely fluid movement associated with the mud volcanoes indicates that it should be possible to estimate the depth of increased pressure and determine constraints on chamber size using InSAR. Modeling of the two large (M_w 6.8 and 6.5) earthquakes near Baku in November 2000 using global catalog locations and focal mechanisms indicates that the deformation from these events should be observable onshore using InSAR.