"cannot perform mergeLayers operation"
*Cause: The two GeoRaster objects whose layers are to be combined together
either had different row or column dimension sizes, or their
georeferencing information did not match.
*Action: Make sure the objects have the same row and column dimension
sizes. If neither is georeferenced, their ULTCoordinate values
must be the same. Otherwise, they must be both georeferenced
and cover the same area in the model space.