It seems pivotal in how civilization moved from Missouri to the Mid-East.
Outside of the flood, the division of the land during the time of Peleg is also important as it is referenced in D&C 133.
18 When the Lamb shall stand upon Mount Zion, and with him a chundred and forty-four thousand, having his Father’s name written on their foreheads.
19 Wherefore, prepare ye for the acoming of the Bridegroom; go ye, go ye out to meet him.
20 For behold, he shall astand upon the mount of Olivet, and upon the mighty ocean, even the great deep, and upon the islands of the sea, and upon the land of Zion.
21 And he shall utter his voice out of Zion, and he shall speak from Jerusalem, and his voice shall be heard among all people;
22 And it shall be a voice as the voice of many waters, and as the voice of a great thunder, which shall break down the mountains, and the valleys shall not be found.
23 He shall command the great deep, and it shall be driven back into the north countries, and the islands shall become one land;
24 And the land of Jerusalem and the land of Zion shall be turned back into their own place, and the earth shall be like as it was in the days before it was divided.
I keep saying the flood is insignificant in the face of that type of cataclysm........ but hey...... not only was the land divided some 4000 or so years ago, a mass extinction did not accompany this event. Actually there is not one bit of evidence supporting this recent division, but the Bible and the modern prophets have taught it occurred and so it occurred. Saying that this is not LDS doctrine is not consistent with D&C 133, nor the teachings of the prophets.