I wonder if you could do the same with magma safe materials and drop rooms right into the magma sea?
I have read something to the effect that people are perfectly capable of doing that, however it is usually best to make sure only the
best and brightest are in the pods at the time, as it is not possible to retrieve them as far as I know.
***UPDATE***The thaw came slightly sooner than I expected. The embark site was on the ice, which thawed. I got the vast majority of my items inside the fortress, only losing a handful of logs. It was pretty obvious when the thaw was coming as all the snow vanished and exposed the ice. Also the snow shifted to rain. There was a fairly sizable delay between these events so I was able to react by making a couple of large "everything" stockpiles.
The water is behaving much like one would expect, falling into the volcano and producing steam and obsidian. The obsidian appears to mostly be caving in, but between the collapse message spam I can't tell if any are actually staying put or not. I think some of the magma has actually gone up a z-level but I am unsure if that will result in anything or not. If the obsidian falling is vertically displacing the magma then it is possible this is going to be more fun than anticipated.
To give you some insight into my present design, I channeled into the ice a little bit so that I could access the same layer as the soon-to-be thawed lake occupied. The circular area that I channeled will serve as an emergency drain when I can get around to digging down and finding the aquifer. I'm going to construct a second bridge on the north side of the "drain" and attach it to the same level so that it can function as an airlock. Hopefully two backup plans will be sufficient to ward away future water-based FUN.
The up ramp leads to the usual preliminary fortress constructions; small stockpile rooms, a couple of workshops, early bedrooms, et al. Nothing worth showing.
Will update once I can determine what is happening with the obsidian being produced.
***UPDATE 2.0***
The obsidian managed to get enough support to stick around and form a lid on top of the volcano. It was really fun to watch it happen, the steam narrowed and the whole thing closed off like a sphincter. I'll leave you to invent the clever butt jokes. Here are the three layers of results.
As it turns out, my lake is only one z-layer deep after all. I am a little disappointed, but there is nothing to stop me from fixing that when I can get around to building a screw pump tower up from the aquifer, which I still need to find.
As things stand, my current plan is to get a screw pump stack up and running as soon as possible. With that up and running I intend to fill the lake to a satisfactory level, at which point I will wait for the next freeze. When the freeze comes I will build pillars in the ice and from there I can construct sky-roads leading off the edge of the map. In the meantime, however, I will need to think of another way to safely house trading partners. I have a lot of upward z-levels to work with as the map is very cliff-happy so I should be able to make a sizable pit trap. Though the bridge airlock did give me another idea.