The Land of Nephi
     …where did it go?

…and there was terrible thunder, insomuch that it did shake the whole earth as if it was about to divide asunder.

And the city of Moroni did sink into the depths of the sea, and the inhabitants thereof were drowned.

…there was a more great and terrible destruction in the land northward; for behold, the whole face of the land was changed…

And many great and notable cities were sunk…

And thus the face of the whole earth became deformed…

And behold, the great city Moroni have I caused to be sunk in the depths of the sea, and the inhabitants thereof to be drowned.

Yea, and the city of Onihah and the inhabitants thereof, and the city of Mocum and the inhabitants thereof, and the city of Jerusalem and the inhabitants thereof; and waters have I caused to come up in the stead thereof…

3 Nephi Chapter 8 & 9