A note on volcanism in Papua New Guinea
Papua New Guinea has 19 active volcanoes 34 potentially active and 26 inactive volcanoes. Volcanic activities are common along the major plate boundaries of Solomon Sea and South Bismarck Sea plates. The subduction interaction between these two micro plates is responsible for the current volcano-tectonic environment in the region. Major volcanic groups are defined by their location in relation to their tectonic relationship. Most active volcanism in the region especially the Bismarck volcanic arc and the Bougainville volcanoes are island arc subduction volcanoes. Although there are more complexities in the relationships between the evolution of the tectonic setting with volcanism and magmatism than what is studied in the region.
Bismarck volcanic arc consists of volcanoes that lie along the Solomon Sea-South Bismarck Sea plate boundary. The East Papuan volcanoes and the D’Entecastreaux volcanoes are related to the Trobriand trough and the Woodlark spreading center or an earlier tectonic setting/configuration that has long been inactive. Admiralty group of volcanoes are North Bismarck intra plate volcanoes that are related to the Manus spreading center. The Bougainville volcanoes are tectonically related to the Solomon Sea plate-Pacific plate interactions along the western segment of its subduction. The New Guinea volcanoes are old inactive volcanoes along older inactive and complex paleo-tectonic settings related to the larger geological synthesis of the various accretionary terranes and island arcs that shaped Mainland New Guinea.