Plate-tectonic evolution and delayed partial melting in Western Papua New Guinea

Abstract

Late Cainozoic volcanoes in the Papua New Guinea Highlands overlie cratonic crust but yet produce arc-type volcanics. The data from the study of these supposedly anomalous igneous rocks suggest that a mantle magma source which has been chemically modified during subduction and which has passed through rapid and pronounced changes in tectonic setting may later on be the source of magmas produced during a favourable but non-arc tectonic regime.