The volcano appears to be of Pliocene age. Only a few outcrops of Mount Moulton have been dated and these yield ages of 5.3 million years, with further age estimates of 4.9 - 4.7 million years ago and 5.9 million years ago; there is no evidence of eruptive or thermal activity unlike at its neighbour Mount Berlin. Earthquakes have been recorded at Mount Moulton and are either of volcano-tectonic origin or due to the movement of ice along the flanks of the volcano.