The Sr, Nd, and Pb isotopic compositions of five Cretaceous guyots (Limalok, Lo-En, Wodejebato, MIT, and Takuyo-Daisan) within the West Pacific Seamount Province (WPSP) indicate that they originated from geochemically enriched mantle sources. They are characterized by large isotopic variations in Pb (²⁰⁶Pb/²⁰⁴Pb = 18.58-19.80, ²⁰⁷Pb/²⁰⁴Pb = 15.55-15.68, and ²⁰⁸Pb/²⁰⁴Pb...
Within the Australian-Antarctic Discordance (AAD), a boundary exists between isotopically defined “Pacific-type” and “Indian-type” mid-ocean ridge basalt (MORB) erupted along the Southeast Indian Ridge (SEIR). This boundary has migrated westward beneath the easternmost AAD spreading segment at a minimum rate of 25 mm/yr since 4 Ma; however, its long-term history...
Lavas from seamounts of the central Galápagos Platform and the Carnegie Ridge increase in age with distance from the western edge of the platform, consistent with a hotspot model for the generation of these features. The areal distribution of seamount ages suggests that the pattern of dispersed volcanism seen on...
