Mount Berlin was active from the Pliocene into the Holocene. The oldest parts are found at Wedemeyer Rocks and Brandenberger Bluff and are 2.7 million years old. Activity then took place at Merrem Peak between 571,000 and 141,000 years ago; during this phase eruptions also occurred on the flanks of Mount Berlin. After 25,500 years ago it shifted to Mount Berlin proper and the volcano grew by more than . Over time, volcanic activity on Mount Berlin has moved in south-southeast direction.