God created one landmass by setting aside the waters that covered the whole earth. Again, only this one landmass emerged after the global deluge. Modern-day geologists call it Pangea.

We read about a person named Peleg in the Bible a little after the time of Nimrod. For in his days was the earth divided; - Gen 10:25. His time is significant in His-story. It was during his days that Pangea broke up and continents (and today’s Oceans and Seas) came into being. Civilizations developed along the river basins and people who spoke a common language started dwelling together for obvious reasons. You can see more here: https://amazingbibletimeline.com/timeline_online/world_history_timeline_23bc/

Huge portions of the original landmass sank under water. Pangea, Lemuria or Kumarikandam, the erstwhile hub of human activity drowned along with its people – all Thamizhar. Kumbalaai Maritha Kandam (the continent that died enmass) might have been the reason for its name.