[GRASSLIST:3690] doubt on map overlay

[Carlos Grohmann]

Hello, I´m new on GRASS and I have some doubts:

I need to make a map of isobase line, wich are isoline
that connect point of equal ´base´ heights. The points
are the intersection beetwen the topography (contour
lines) and second-order rivers.
The idea was to import my dxf maps, convert them to
raster and overlay to get a "points" (sites) map, and
finally use the sites map to produce a DEM.
I did all this, but the sites don´t have the height
value. 
There is something I´m doing wrong, in the middle of
the process, but I don´t know what is it.

Can anyone help me with this? 

Thanks in advice.

Carlos Grohmann




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+-------------------------------------------------+
   Carlos Henrique Grohmann de Carvalho - Guano   
               Geólogo - Geologist
+-------------------------------------------------+

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