I've read the Gilgamesh translation and I agree, the similaraties are unmistakeable. I have (all this time) accepted the idea/theory that they originated from the same source also. It's that 2,900 year gap that is the problem. Until I checked out these dates, I had just accepted that the Black Sea flood was Noah's and that it was the source of both these stories, Noah/Gilgamesh. Now I don't know what to think. Hmmmm
One would speculate that they were part of the same event; i.e., that the Black Sea flooded as a part of some larger phenomenon; your impact in the Shaat al Arab aera for example.