Interplate grid file (Ascii Surfer Grd) to Modflow

[GMS User]

I imported a Ascii grid files created with Surfer and then I interpolated it to the 3d grid I build for Modflow.

Surfer grid and GMS 3d grid have different cell size, dimensions and active cells.

Everything worked fine.

I was wandering if it will be possible to interpolate the Surfer grid only to the Active cells of the 3d grid used for Modflow, in order to get an overlapping countouring level.

Thank you

Daniele

[Michael Kennard]

I'm not sure I understand your question. Are you asking if the interpolation acts on all grid cells or only the active cells? Or are you asking a different question?

If you use the "Interpolate -> MODFLOW Layers" command it will only affect the active grid cells (IBOUND != 0). If you use the "Interpolate -> 3D Grid" it will create a new data set and will interpolate to all cells regardless of IBOUND.

[GMS User]

You understood my question.

The desired effect is the one obtained by running "Interpolate -> MODFLOW Layers", but I would like not to use the command as it will affect the starting heads.

I would like to compare Modflow computed heads with the ones obtained by grid interpolation.

Thanks

[Sean Czarniecki]

Sounds like you can do what you want by making a separate data set of your starting heads first (Grid -> 3D data set). Do your interpolate -> MODFLOW layers....then make that into a data set (either 3D or make specific layers into 2D data sets). You can then pull your starting heads data set back into your grid. You now have the data sets available for display. That *should* work for you.

[GMS User]

Thank you for your suggestions.

I was thinking to a simple tool : blank cells (Surfer) or clip grid (Rockworks) inside/outside a polygon. The polygon could be the coverage used to define the active cells for Modflow,