Max Webb, Lloyd White & Robert Hall


The aim of this study is to understand the petrogenesis, age and deformation history of the Netoni Intrusive Complex located in the northern Bird’s Head. This will be achieved by mapping and collecting samples of the Netoni granitoids on the northern and southern side of the large Sorong Fault Zone (SFZ). Samples from either side of the fault zone will be characterized on the basis of petrological, geochemical and geochronological data.



The Netoni Intrusive Complex represents a suite of granitoids (quartz monzonite, granite, quartz diorite and diorite). These are reported to have been emplaced during the Triassic to Cretaceous (240-78 Ma) on the basis of hornblende and biotite K-Ar dates from float material. Early maps indicate that the southern margin of the plutonic complex is cut by the Sorong Fault Zone (SFZ), a major east-west trending, strike-slip fault system several hundred kilometres long. However, reconnaissance mapping by David Gold (SEARG) indicated that granitic material is also prominent on the southern side of the Sorong Fault Zone.