It is pretty much guaranteed that my world would have very intense tectonic activity, plus it would be about 23% smaller than the earth and I have been wondering how that would influence the civilization inhabiting it.
How would an advanced civilization close to achieving an interplanetary status develop it's cities on the planet? Would they built up? With arcologies and similar structures? Or would they build downwards? With underground structures and artificial caves? Or would they mix both things, building both underground and above ground?
Here is a bit more information about the world:
It is a moon of a gas giant, therefore expect a lot of tidal flexing, which would create conditions akin to Japan.
Mass: 0.7 Earths Diameter: 0.88 Earths Density: 5.6 g/cm(3) - Very iron rich
On a side note, if the world's tectonic activity was mainly in the form of volcanism without the earthquakes, how would that affect the civilization's architectural preferences?