They can't be "vaporizing," when there's clearly no vapor produced-- nor any trace of the substance whatsoever. This means that the material is either is shifted out of the continuum entirely, or else it's broken down into such small particles that they simply pass through the surrounding material completely without noticable incident.Jedi Master Spock wrote:. Phasers don't do violent blasting. They can melt, but when you crank them up high enough to vaporize, you get non-violent disintegration as a result, usually. Why? We don't know.
For the E-D to blast its way out through the molten rock is likeliest to mean disintegration of that tube of rock.
More like the Romulan captain would say "oh my, those asteroids certainly are unstable-- how unfortunate that they chose to go inside it..." as he blasted it from the outside.