indicator_geology has no concept of layers.  EVEN IF it sometimes results in something that looks like layers, we must treat the general case where the MATERIALS can be arranged in bizarre ways that do not resemble stratigraphic layers at all.
First, I need to say that there is no simplistic (automatic) output to MODFLOW or even our preferred modelling program Groundwater Vistas.  However, there are a number of users who have used indicator_geology to help initialize groundwater models.
Here are our recommended methods/guidelines:
  • Use Finite Difference gridding in krig_3d_geology
  • You will still need to create your model layers using a .GEO or .GMF file.
  • You can use indicator_geology (reading a PGF file) to assign material properties based on the material assignments it makes:
    • Don’t use the “Smooth” option, since you won’t want it to subdivide cells
    • You’ll need to set up a correlation between Material integer values and material property values.  This could be done with node_computation or done outside of EVS.