Green monolith locations? (Not asking for coordinates or clues)

[MaverickSawyer]

I just revisited the randomly-placed green monolith on Minmus last night, and had an odd thought: Does it ever spawn on the flats, or does it always spawn in rougher terrain?

This led me to another thought... is there a set of parameters used to determine where the green monolith spawns, or is it completely random? I'm inclined to believe that it's not entirely random, because then you'd have to dive to find them on Laythe, Eve, and Kerbin, and I've not heard of that happening.

[bewing]

You'll have to ask @Arsonide.

[KerbolExplorer]

I guess they spawn in some biomes selected by the devs.

You can easily find monoliths with ScanSat