S. Fujiwara et al., Surface displacement of the March 26, 1997 Kagoshima-kenhokuseibu earthquake in Japan from synthetic aperture radar interferometry, GEOPHYS R L, 25(24), 1998, pp. 4541-4544
A JERS 1 differential L-band synthetic aperture radar (SAR) interferogram o
f the March 26, 1997 Kagoshimaken-hokuseibu earthquake (M-w=6.1) in southwe
stern Japan shows about 9 cm peak-to-peak coseismic surface displacement in
the radar line-of-sight (LOS) direction. A permanent GPS array detected 1
to 2 cm horizontal displacements from this earthquake. By inverting the SAR
and GPS data together, we estimated a fault mechanism without any seismolo
gical data. A theoretical radar LOS displacement pattern from a single faul
t model of the earthquake motion matches the SAR and GPS observations close
ly. The model assumes left lateral slip of 0.46 cm with rake angle of 19 de
grees on a rectangular fault plane of dimensions 11 km (width) by 12 km (le
ngth). We demonstrate that L-band SAR interferometry can describe several c
m surface displacement in detail and construct a fault model. However, desp
ite the acquisitions being during the cold season, there are apparent water
vapor signatures in the interferogram with equivalent path delays of up to
1.5 cm.