好像还真有点儿关系

我的理解是， Atlantis (lost city) 和 Atlantic (ocean), 来自于泰坦神 Atlas, 和Atalanta 没啥关系。

Atlanta(city), 是致敬前州长女儿的名字。前州长女儿的名字是Atalanta:

The city was named for former Governor Wilson Lumpkin’s daughter’s.
Her middle name was Atalanta, after the fleet-footed goddess.

( https://www.americannamesociety.org/how-atlanta-got-its-name/? )