HELP Multiple Attractor Points to generate domes on surface

I need Help!

I have created a surface with responds to attractor points. The problem being the maths isn't doing as I hoped.

Currently every surface point is being affected by the attractors.

I want each point to work on a field of attraction which moves points near it in the Z direction to create a dome like shapes, with the rest of the surface remaining flatter?

I think this means I need to set a distance to the attraction so that not every point will be affected.

Any other ideas are welcome to whether this is achieveable in GH

I have attached a few sketches to help explain the result I am looking for.

Thanks for the help