[RightWhale]

the sea level is much higher now

Sea level has risen, but more like 300 feet than 2000 feet. If this is a city, it must have sunk 1700 feet or so, which is unusual. A big methane pocket underneath might have erupted, but even big earthquakes don't normally move land vertically more than a few feet. Parts of Anchorage shifted 20 feet in the Good Friday earthquake and they lost their seaport.

[aruanan]

Well, I suppose that should these things prove to be what they appear to be it goes without saying either that the sea level has risen much more than 300 feet or that there has been subsidence to a great degree or both.

[blam]

"Sea level has risen, but more like 300 feet than 2000 feet. If this is a city, it must have sunk 1700 feet or so, which is unusual."

Could the Gulf Of Mexico have been isolated for a while like the Black Sea? Partial dessication? Food for thought.