Figure 7a. Ratio image July 9/August 13. : 
  
    
  
  
  
  
1 
Figure 7b. Lahar limits extracted from the ratio image. 
1 nbpim: 227 surface (m2) : 35468 
Zz nbpix ; 124 surface (m2) : 19375 
3 nbpix : 153 surface (m2) : 23906 
4 nbpix : 11946 surface (m2) : 1866562 
5 nbpix : 2760 surface (m2) : 431250 
6 nbpix 4 162 surface (m2) : 25312 
7 nbpix : 366 surface (m2) : 57187 
8 nbpix : 867 surface (m2) : 135468 
9 nbpäx 552 surface (m2) .: 86250 
iG nbpix 170 surface (m2) : 26562 
ND nbpizx _; 187 surface (m2) . 29218 a 
  
Figure 7c. Coverage of lahar, in square meters, along test area in Bucao River. 
  
Figure 7. Lahar-limit extraction from ERS-1 SAR data using filtering, ratioing and 
segmentation techniques developed by J. Parrot. 
  
  
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B7. Vienna 1996