The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Voi. XXXVII. Part Bl. Beijing 2008 
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Figure2 Subsidence monitoring method based on time serials of interferograms 
Figure 3 Subsidence 1996.1-1997.10. The subsidence regions 
can be seen clearly and the color coding indicates the 
magnitude of subsidence. TM (1999, band: 321) image is 
shown in the background, and overlapped with the mine area 
map (solid black line).The largest displacement is 9cm in West 
of Tangshan, In Tangshan Mine area, it has averagely 7cm 
displacement, in Gangyao Mine and Majiagou Mine, and it has 
1.5cm displacement. 
Figure 4 Subsidence 1997.10-1998.5. ETM (1999, band: 321) 
image is shown in the background, and overlapped with the 
mine area map. The largest displacement is 18cm near 
Majiagou mine, in Gangyao mine, it has averagely 8 cm 
displacement, and Tangshan mine area has 7cm displacement. 
In west of Tangshan mine area, and it has averagely 3 cm 
displacement due to the Kast collapse.