What features of an alien planet would you look for in order to determine if the planet experiences plate tectonics?
Earth's crust is made of large moving plates. Where the plates meet are called plate boundaries.
There are three types of plate boundaries: Transform, divergent and convergent.
When it comes to transform plate boundaries, plates move past each other, like the San Andreas Fault Line.
Mid-ocean ridges are created by divergent plate boundaries moving away from one another.
Tectonic Plates move towards one another at convergent plates. Earthquakes and composite volcanos are frequent at convergent boundaries when moving towards one another. This also forms Mountain ranges.
When these plates move, the land moves with them, as the continents did on Earth as well.