That Frazer quote is also in “Noah’s Flood” — the authors of that book claim that the folklore about the flood coming *out* of the Black Sea was a consequence of the migration of some survivors of the Black Sea flood from the now-submerged basin to Samothrace. That’s a pretty weak explanation IMHO, particularly since the submerged towns could still be seen off Samothrace during antiquity. :’)
it looks like such a small crack:
push both sides together, nice fit? Earthquake...
...the Strait of Gibraltar. Oooh
looks like a nice submarine fan building out into the Atlantic right out of the strait.