Landmasses and ocean basins rose and fell dramatically! One scientist observes:
“Marine volcanic islands which have been truncated by the waves and since subsided below sea level are called guyots. Most of them seem to have sunk by 600 to 2,000 m [2,000 to 6,500 ft] and it is evident that they afford a measure of the amount by which the ocean floor has sunk in late geologic time. … All the ocean basins afford evidence of subsidence (amounting to hundreds and even thousands of metres) in areas far from land.”7
Read more about it here: https://creation.com/how-did-the-waters-of-noahs-flood-drain
