If in the Pacific it’s from the lost continent of Mu.
Writers have mixed the two up in explaining various discoveries and underwater evidence, but the one in the Pacific was much earlier than Atlantis and explains the flood legends better as originating from survivors of this catastrophe who escaped to the Americas, Asia, and the near East.
The mythical idea of the “Land of Mu” first appeared in the works of Augustus Le Plongeon, after his investigations of the Maya ruins in Yucatán.
He claimed that he had translated the first copies of the Popol Vuh, the sacred book of the K’iche’ from the ancient Mayan using Spanish. Yucatán was older than those of Greece and Egypt, and told the story of an even older continent.
The lost continent of Mu was first proposed in the mid-19th century to explain the phenomenon of similar symbols, architecture and myths found in otherwise disparate, ancient cultures around the world.
It was subsequently popularized as an alternative term for the hypothetical land of Lemuria by James Churchward, who asserted that Mu was located in the Pacific Ocean before its destruction.
[link to guardian.ng (secure)
With the knowledge bestowed on him by the religious elder, Churchward went on to describe the people of Mu as an advanced civilization called the Naacal who existed between 50 000 and 12 000 years ago. At the height of their civilization they were said to have 64 million inhabitants living in large cities…the continent was finally destroyed in only one night by a series of earthquakes and volcanic eruptions.
[link to mythology.net (secure)