So i had this awesome idea to make an obsidian tower in the middle of a glacier, a midnight black structure stabbing into the sky on a featureless white plain. Constructed directly over a magma pipe, it would have lava pumped through a central capillary to a reservoir under the roof to keep snow from gathering on the top of the tower and veins of lava from this artery inside the tower to power forges and heat bedrooms. Maybe even lava-falls pouring down the sides of the tower. At the base of the tower there would several structures laid out: a block of windmill farms to power the lava pumps, an obsidian factory, an ice factory and some other thing to keep it symmetrical
. Maybe two of something. Ooh, why not an arena. There would be large chambers dug out of the permafrost to hold material stockpiles, a dungeon/jail, a gobbitorium and a wild polar bear breeding cave for use in the arena against gobbos. The entire compound would be surrounded by a wall made of mined and manufactured ice with gates guarded by tethered (tamed) polar bears.
Unfortunately the site required for such a structure would need very specific features.
1. It would have to be a glacier.
2. It would have to have a magma pipe.
3. It would have to have an aquifer.
4. The magma pipe would have to be in the same biome as the aquifer layer.
5. The magma pipe would have to be at least 3 local squares into the region square so it will be centrally located in the fortress map.
6. The magma pipe would have to start right under the ice, preferably with an obsidian 'plug' in the ice.
7. The glacier would have to not be 'deathly cold' so that merchants won't freeze to death. (it would be quite troublesome to grow food/booze.)
8. The glacier would have to have snow throughout, cuz bare ice mixed with snow covered ice would ruin the effect.
Now the only way to get an aquifer under a glacier is to have a conglomerate or sandstone layer right under the ice. These are both sedimentary layers, so these would usually be replaced with igneous stone near volcanic areas. Sometimes a magma pipe can be found beyond the edge of the igneous layer and in a sedimentary layer, but such pipes are usually found right on the edge of the region square so it can't be centrally placed in a fortress.
Anybody found such a spot before? If not, anybody have a good set of worldgen parameters with lots of glaciers and a good amount of volcanism? I'd really like to make this fortress a reality.