This mod adds rich ore veins to biomes, but does not remove vanilla ores.
Desert, savanna, and mesa biomes contain more gold and copper.
More emeralds and iron can be found in the mountains.
Snow biomes contain more diamonds than other biomes.
Swamps and mushroom fields contain more coal.
Taiga and dark forests contain more iron.
Forests, birch forests, and old growth forests contain more redstone and lapis lazuli.
Meadows contain more lapis lazuli.
Cherry groves contain more redstone and copper.
Plains contain more copper and iron.
Jungles contain more gold and iron.
(The mod is currently in Beta, so the list is incomplete at the moment.)