Anantha
Couldn't you use a mask so that the surface is only fit for the land areas?
I reckon that for anyone who is working near coastlines in grass, a very
early requirement is to make up a cell mask for either/or the sea and the land
! 
Simon Cox
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Dr Simon Cox
__ L
,~' L_|\ Department of Earth Sciences
,-' \ Monash University
( \ Clayton Vic 3168 Australia
\ ___ /
L,~' "\_x/ Phone +61 3 565 5762
u Fax +61 3 565 5062
simon@cerberus.earth.monash.edu.au
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