Volcanic and Magmatic History of Papua New Guinea
Cenozoic tectonics of the southwest Pacific are defined by multiple episodes of large-scale tectonic reorganization driven primarily by major collision events, such as the collision of the Ontong Java Plateau with the Melanesian arc, and the collision of the Australian continent with New Guinea. However, the nature and timing of these events are under dispute, which in turn compromise our understanding of even the basic regional geodynamic framework of the southwest Pacific. Studies of the nature of arc magmatism through time – particularly during periods of tectonic change – can provide us with insights into subduction dynamics and crustal processes that may be difficult to resolve via other means.
The Maramuni arc of Papua New Guinea, for example, represents the only continuous tectonic element throughout the dynamic Miocene, marked by complex collision events and orogenesis. Therefore, the Maramuni arc presents an ideal setting to examine the tectonic and geodynamic processes associated with arc magmatism, subduction, orogenesis, continental growth and mineralization. Of additional significance, the Maramuni arc of Papua New Guinea and West Papua hosts some of the world's largest subduction-related porphyry ore deposits including Ok Tedi, Frieda River, Porgera and Grasberg.
This research utilises detailed geochemical and geochronological investigations into the volcanic and magmatic history of Papua New Guinea to inform regional geodynamic models to help explain the complex tectonic history of the region, and also address complimentary geoscience branches such as volcanism and natural hazards.