Palaeotsunamis and their influence on Polynesian settlement

Abstract

The 11 March 2011 Tōhoku-oki tsunami caused widespread devastation to coastal communities in Japan. This event however was merely the latest, yet largest, of several similar occurrences in the Pacific that include the 2007 Solomon Islands, 2009 South Pacific and 2010 Chilean tsunamis. All have had their predecessors, and a growing data base of palaeotsunamis in the Pacific suggests recurrent events comparable with, and of larger magnitude than their recent historical counterparts. Here we show that evidence for regional palaeotsunamis provides an opportunity to re-evaluate hypotheses used to explain the punctuated history of human settlement patterns across the Pacific. In particular, the almost two millennia ‘long pause’ in eastward migration, and the abandonment of long distance sea-voyaging in the 15th century, may be related to palaeotsunamis, with potential sources including the tectonically active Tonga-Kermadec trench, the Kuwae caldera collapse, and the more distant Pacific-wide Ring of Fire.