So I posed a question (Calamity breaking a supercontinent in days - Would there be any survivors?) about a calamity that would break a Pangea-like supercontinent in a matter of days. I assume that the only way to do this is through a set of divergent plate tectonics.
However, I would like to know if it is possible to create de novo mountain ranges on the edges that separate the newly formed continents. I don't know if this will be possible, since divergent plates don't form mountains... would I need convergent plates to do that? Or is there any realistic way to produce this effect?
Could I maybe use the aforementioned catastrophe to produce the mountain ranges?