Changbai Mountain Volcano Group Changbai Mountain is part of the ancient summer mainland, is a famous dormant volcano, about 600 million years ago, here is a sea of ocean, from no ancient to Mesozoic, after the Earth experienced the Caledonian Sea, Yanshan and Himalayas movements, The sea finally retreated from this ancient land, and a series of fractures and uplifts occurred in the crust of Changbai Mountain, where basalt magma flowed underground