“…(c) FeO*/MgO versus SiO2 (wt. %) and age ranges for plutons from: Amatignak Island (red squares), Finger Bay Pluton (orange circles), Hidden Bay plutonic complex (blue diamonds) [ Citron et al , ; Kay and Kay, 1982; Kay et al , , 1990], Attu Island [ Delong and McDowell, 1975; Yogodzinski et al , ; Sheldon, 1986], Ilak Island (brown circles; Fraser and Barnett, 1959; Wilson et al , ), Amchitka's East Cape pluton (black diamond) [ Kay, ; Jicha et al , ] Unalaska's Captain Bay pluton (yellow circles) [ Marlow et al , ; Perfit et al , ], Atka pltuons (gray circle) [ Hein et al , ], and Kagalaska pluton (pink diamond) (Kay and Jicha, unpublished). Calc‐alkaline and tholeiitic fields from Miyashiro [].…”