Sun, W.W.SunZhang, H.H.ZhangLing, M.-X.M.-X.LingDing, X.X.DingSUN-LIN CHUNGZhou, J.J.ZhouYang, X.-Y.X.-Y.YangFan, W.W.Fan2020-05-152020-05-152011https://scholars.lib.ntu.edu.tw/handle/123456789/493248Adakites may form by partial melting of either the subducting oceanic lithosphere or the lower part of the continental crust. These two magma types can be discriminated geochemically using a combination of La/Yb, Sr/Y ratios, MgO and Na2O contents, and Sr�VNd isotopes. Given that the basaltic crust has Cu concentrations more than two times higher than the lower continental crust and the mantle wedge, ��primitive�� adakites produced by oceanic slab melting should contain significantly higher Cu contents than adakites derived from the continental crust, as well as normal arc andesites. A globally compiled dataset shows that Cu concentrations in adakites are generally lower than that in normal arc rocks. We attribute this low copper content to loss of magmatic fluids as a result of sulphate reduction during adakitic magma differentiation, in turn induced by the crystallization of Fe�VTi oxides, essential to mineralization. Therefore, the underflow of oceanic-slab-derived adakites that can release larger amounts of Cu (presumably Au as well) by crystal fractionation leads to higher potential for Cu�VAu mineralization along convergent margins, usually associated with ridge subduction. Such basaltic slab melts initially have considerably higher Cu contents and thus play a crucial role particularly in the relatively closed magma system responsible for generating porphyry Cu deposits.[SDGs]SDG14other10.1080/00206814.2010.5073622-s2.0-79952013116https://www.scopus.com/inward/record.uri?eid=2-s2.0-79952013116&doi=10.1080%2f00206814.2010.507362&partnerID=40&md5=21b8b19e6794f18e560be0d9eb636ad9