The breakup of pangaea was due to rifting. It was probably never a consolidated single continent, as we think of them today.
More likely, it was like Africa/Asia, and North/South America, with somewhat narrow connections in places.
http://webspinners.com/dlblanc/tectonic/pangea.php
There is one flood that might have been the flood described in Genesis. The breaking of a landbridge that allowed the flooding of the Black Sea area would have been about the right time; and there is evidence that settlements were flooded, not so rapidly that no one could escape, but fast enough and large-scale enough to have been frightening to those who experienced it.