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International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B7. Istanbul 2004
observed changes in range from the ground surface to the
satellite agree well with the slip measured in the field, with the
displacement measured by surveying, and with the results of an
elastic dislocation model.
With suitable SAR data set and processing methods, SAR
differential interferometry can capture high-spatial-resolution
co-seismic displacements and surface deformation information
on the order of centimeters, without advance knowledge of the
earthquake's location by removing the signal from the
topography. But it is notified that fringe indications on the
differential interferogram represent only the shift of every pixel
along radar viewing direction, the actually surface deformation
displacement maybe trend vertical or horizontal direction, or
slant direction, furthermore maybe the comprehensive
deformation displacement along various direction. Thus, the
deformation interpretation of the differential interferogram and
fringe patterns could be various. Our observations show that
there is localized heterogeneity in the deformation field of the
Mani earthquake within 270 km of the main rupture. This
discrepancy could be resolved with further modeling of the
displacement expected from an elastically responding
lithosphere and comparison of models to interferometric results.
Radar differential interferometry has generated enormous
interest in the China’s Earth science community because they
point to an entirely new way to study the surface of the Earth, it
is grandly significant to earth sciences, especially to seismology
studies. Also it will become an essential technological method
to monitor, assess, and relieve earthquake activity, combining
with GPS, imaging-spectral sensor, and thermal infrared sensor
et al. remote sensing new technologies. It is expected that the
technique and its applications of SAR differential
interferometry will develop rapidly with the development of
radar remote sensing in China.
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ACKNOWLEDGEMENTS
The project is supported by the Foundation (Grant No.
SK040002) of State Key Laboratory of Remote Sensing
Sciences, CAS and the NJTU Intellectual Foundation of China
(Grant No. TJJ03002).