西太平洋麦哲伦海山区是重要的富钴结壳成矿区，被认为形成于南太平洋同位素和热异常区，因此是研究洋岛玄武岩（OIB）源区组成和成因的重要靶区。而其岩浆起源、演化和岩石成因仍不清楚。本项目拟对麦哲伦海山区四座海山玄武岩进行系统的岩相学、主量和微量元素以及Sr-Nd-Pb同位素分析，并首次开展Hf同位素分析，通过模拟计算识别DMM、EM1、EM2、HIMU和FOZO端元对其源区贡献比例，揭示主量元素和不相容元素比值与Sr-Nd-Pb-Hf同位素之间的关系以及Nd-Hf同位素之间的耦合关系，结合OIB源区各种潜在物质来源的地球化学特征，揭示本海山区玄武岩岩石成因，深入探讨麦哲伦海山玄武岩源区组成和形成过程，对进一步认识OIB源区组成和成因具有重要意义。本项目研究成果还将为我国已经开展的西太平洋海山区的富钴结壳勘探提供岩石学和地球化学方面的基础资料。

The Magellan Seamounts in the West Pacific Seamount Province are prime areas for mineralization of Co-rich Mn crusts and are interpreted to be derived from the South Pacific Isotopic and Thermal Anomaly. Thus the Magellan Seamount basalts are good candidates for studying the source component of ocean-island basalts (OIB). However, it remains unclear concerning their magmatic evolution, magma source component and petrogenesis. We employ a systematic and detailed petrographical, major and trace element and Sr-Nd-Pb-Hf isotope approach to investigate the relative contribution of DMM, EM1, EM2, HIMU and FOZO in the mantle source of the Magellan Seamounts. Using these data, we attempt to unravel the relationships between major elements and ratios of incompatible elements and Sr-Nd-Pb-Hf isotopes, and Nd-Hf isotopic correlations. Combined with distinct geochemical characteristics of OIBs derived from different mantle sources, these results allow us to further investigate the source component of the Magellan Seamounts and their petrogenesis. This has bearings on the source component and origin of global OIB and provides petrological and geochemical inferences for the prospecting of Co-rich Mn crusts on the Western Pacific seamounts.