Direct Associations Between Potassic Igneous Rocks and Gold-Copper Deposits

Abstract

An overview of spatial associations between potassic igneous rocks and gold-copper deposits in the Southwest Pacific area is shown in Figure 6.1. Examples of direct associations between potassic igneous rocks and copper-gold deposits investigated in this study are, in order of increasing age: The Quaternary Ladolam gold deposit, Lihir Island, Papua New Guinea (Wallace et al. 1983; Plimer et al. 1988; Moyle et al. 1990; Dimock 1993; Hoogvliet 1993). The Tertiary Emperor gold deposit, Viti Levu, Fiji (Gill 1970; Colley and Greenbaum 1980; Anderson and Eaton 1990). The Pliocene Porgera gold deposit, Papua New Guinea (Handley and Henry 1990; Richards 1990a, 1990, 1992; Richards et al. 1990, 1991). The Eocene Bingham copper deposit, Utah, USA (Lanier et al. 1978a, 1978b; Warnaars et al. 1978; Bowman et al. 1987). The Eocene Twin Buttes copper deposit, Arizona, USA (Titley 1982; Barter and Kelly 1982). The Mesozoic to Recent Chilean Andes which host many epithermal gold and porphyry copper-gold deposits (Gustafson and Hunt 1975; Dostal et al. 1977b; Deruelle 1982; Gröpper et al. 1991; Sillitoe 1991; Vila and Sillitoe 1991; Hildreth and Drake 1992; Clark 1993). The Ordovician Goonumbla porphyry Cu-Au deposit, New South Wales, Australia (Heithersay et al. 1990; Müller et al. 1994).