how to depict an underground cavern in 2D model

  Hi everyone!
  I am now working on the pressure distribution around an underground cavern with a stable water pressure beyond it.
  Then I wanna depict the shape of the underground cavern in 2D model, how can i realize my idea?
  Thanks~

I guess you'd have to describe the system you would like to simulate a bit more in detail to enable forum members to direct you, e.g.: horizontal/cross-sectional model, conditions in the cavern, ...

Thanks Peter for your suggestions.
I wanna set a cross-sectional model, which can show the location and the shape of the underground caverns excavated with a series of horizontal boreholes injected with water to keep a stable pressure above the caverns at a certain depth, to simulate the pressure distribution between the caverns and boreholes above the caverns.

Holes in 2d models can be set up in the super mesh...holes would have no super elements.