[GRASS-user] artifacts in interpolation

[Carlos "Guâno" Grohmann]

Hy all.
I was resampling some DEMs with RST and kriging, and the results have
these weird artifacts,  take a look:

http://www.igc.usp.br/pessoais/guano/temp/krig_artifact1.ppm

This is the region of the original SRTM

g.region n=7435400 s=7413260 w=284870 e=309890 res=90 save=japi
projection: 1 (UTM)
zone:       -23
datum:      sam69
ellipsoid:  sam69
north:      7435400
south:      7413260
west:       284870
east:       309890
nsres:      90
ewres:      90
rows:       246
cols:       278



and this is the one I am using to resample

g.region res=30 save=japi30
projection: 1 (UTM)
zone:       -23
datum:      sam69
ellipsoid:  sam69
north:      7435400
south:      7413260
west:       284870
east:       309890
nsres:      30
ewres:      30
rows:       738
cols:       834


Any ideas?
thanks

Carlos

-- 
+-----------------------------------------------------------+
              Carlos Henrique Grohmann - Guano
  Geologist M.Sc  - Doctorate Student at IGc-USP - Brazil
Linux User #89721  - carlos dot grohmann at gmail dot com
+-----------------------------------------------------------+
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