The Wafi-Golpu Cu-Au porphyry system is located in the Marobe Province in Papua New Guinea approximately 65 km SW of Lae. It is owned by the Wafi-Golpu Joint Venture (WGJV) which is a joint venture between Harmony Gold and Newcrest Mining. The total mineral resource for the system as at December 2017 is estimated at 27 Moz Au and 8.6 Mt Cu. There are three major deposits; the Wafi high sulphidation deposit and the Golpu and Nambonga Cu-Au porphyry deposits.The Wafi-Golpu project area is hosted within the 25km NNE trending Wafi Transfer Zone. It lies along the eastern margin of the Aure Trough - a geosynclinal structural basin that developed during the Tertiary period and is mainly composed of turbidites and volcaniclastic sediments (Newcrest 2012). The regional geology and RTP magnetics are shown in Figure 1. CITATION: Hoschke, T and Frankcombe, K, 2019. Processing of historical geophysical data as an aid to mapping alteration and mineralisation in the Wafi-Golpu porphyry system, Papua New Guinea, in Proceedings PACRIM 2019, pp 6265 (The Australasian Institute of Mining and Metallurgy: Melbourne).