INVERSION OF SYNTHETIC APERTUR,E R,ADAR (SAR) - MSpace ...

in Figure 6.19 tvhich is a clilect adclition *'ith ulit iveighting factols, details
of rnany srnall geologic featules have disappea-.-ecl because of the rnany scattered
bliglit spots. In Figure 6.20 where the weighting factols rver.e a:0.75
ancl ó : 0.75, lalge surface geologic featules of tlie North Range (northrvest
parts in the image) are letained, and both ly'l4ltr4l-tlencling lineartetts of
airl¡olne SAR clata ald lViVl4/-trencling linearnents of ERS-1 SAR clata are
relatively well visible. Geologic featules inside the Suclbur.y Basin structule
are l¡lur.,-ecl rvhen cornpared with tlie oliginal airborne clata in Figule 6.5,
Northeast trelcling linear features along the Nortli Range ale also haldly
visible.
Instead of additive process, trvo SAR data sets can be combìned thr.ough
a subtraction. The following subtlactive operation usecl is:
DN".- : DNt I o' (DNA -
DNB) (6.15)
where ¿ is a constant factor'. Two subtractive irnages were generatecl by
using a factor ¿ : 0.5 (FiguLe 6.21) and ø : 0.4 (Figure 6.22) using two
original airbolne and ERS-1 SAR data sets. In a similar rnanner to the
additive irnages shown il Figule 6.20, geologic features in the North Range
have retainecl chalactelistics of l¡oth airborne (lVl4llü-tr.endilg linearrelts)
ancl ÐRS-1 (ÂWtr42-trencling lineaments) SAR data. Features inside the loiv
lelief Sudbuly Basin area ale less clear thar in the original ailbor.ne SAR
image (Figule 6.5), but are better inagecÌ than the aclclitive images shown
in Figure 6.19 ancl 6.20. Noi'theast tlending lineal featules along the Nor.th
Range are not so clistinct as the original SAR data in Figules 6.5 and 6.6.
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