The volcano was formed by subaerial eruptions between 1.54 and 1.28 million years ago.
[2] Activity on Pago Volcano ended with emplacement of trachyte bodies with ages of 1.03 ± 0.01 Ma.
[3] The Pago Volcano caldera was formed 1.27+-0.02 million years ago.
The northwest rim, Maugaloa Ridge, creates the southern border of the National Park of American Samoa.
[5] Mount ʻAlava is part of the caldera rim of the Pago Volcano.