From Halopedia, the Halo wiki
Riptide Xeno-Oceanographic is a formerly underwater research facility constructed by Imbrium Machine Complex. It is situated on a human colony world that was taken over by the Created led by Cortana, shortly after October 2558. Scarred by wars both ancient and recent, the planet was deemed in need of significant alterations by the Created. Utilizing terraforming equipment, they are in the process of shifting continents and oceans based on carefully balanced benefit and drawback analyses of both limited extinction events and damage to the existing colonial infrastructure.
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