Idea: Simulate a small section of magma as it ascends through the conduit. As the magma rises the pressure decreases and it undergoes a liquid gas phase-separation. This phase-separation is associated with an increase of the volume of the section we are simulating.

We simplify the system to contain only two components: the material that will transform into the gas and a second component that will remain liquid (and in a later version will also solidify).

I tried to put in some latex, but I got the message: Access check on LatexModePlugin failed. Action "CHANGE": access not allowed on web.

We will use an underlying free energy, maybe of the form %$ F = \int \left[ \rho_a \log \rho_a ... \right] $%