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correction of the geometry radar image strips of the areas at both sides 
from the aeroplane can be made. 
The hyper wide angle characteristics of the image formation technique 
makes application in hilly terrain almost impossible (25). However, recent 
development of high altitude flown SAAR gives better image-geometry for 
hilly terrain. The most likely areas to be flown with radar are very 
large tropical areas where meteorological conditions do not allow for 
good aerial photography or MSS satellite coverage. 
The scale of radar images varies from 1:100,000 to 1:400,000, whereas the 
resolution can reach up to 30 x 30 meters for SLAR and up to 10 x 10 
meters with SAAR. In the near future, pixel sizes of 3 x 3 meters will 
become feasible. 
6.2 Type of information provided by radar imagery 
  
Radar imagery provides information on reflective capacity of the earth's 
surface (or vegetation) as well as on the terrain slope. This is the 
reason why the main morphological aspects of an area are visible in a 
radar image. Large structural geological elements as folds and faults can 
be recognized if they have sufficient morphological expression (26,21). 
A problem in radar imagery interpretation is that linear elements of 
patterns are better visible, when they are perpendicular to the scanning 
direction than those which are parallel to the scanning direction. 
Stereo impression is obtained, when parallel and overlapping strips are 
examined under the stereoscope, but the stereomodel is too unreliable to 
allow strict morphological conclusions. 
— Rock and soil units. The small scale and poor resolution enable only 
very rough zoning of some regional units of soil and rock. Conclusions 
on engineering properties of rock or soil cannot be drawn from radar 
imagery as there is no direct relation between these properties and 
the process of scattering and reflection which play a part in radar 
image formation. 
- Hydrogeology. Larger surfaces of water such as lakes and broad rivers 
give specular reflection and are clearly visible on radar images due to 
the strong contrast with the surrounding rock and soil. Drainage lines 
of minor importance may be visible, if they are reflected in the 
morphology of the area, but a bias of better visibility of drainage 
lines parallel with than perpendicular to the flightline is observed.