Abstract:

The elemental and isotope geochemical characteristics of oceanic island basalts can be used to trace chemical structure and
chemical evolution of the deep mantle. HIMU (Highμ,μ=238U/204Pbt=0) -type basalt is a kind of oceanic island basalts which has unique elemental and isotopic composition and is thought to be directly associated with recycled oceanic crust in the mantle plume. Therefore, the genesis of HIMU basalts is a long-term topic of the mantle plume (hot spot) researches. This paper summarizes the geochemical definition, distribution, stages of volcanic evolution and changes in lithology of HIMU-type ocean island basalts.Furthermore, we discuss the differences of the source compositions and genesis between classical HIMU basalts and other intraplate basalts against their elemental, radiogenic isotopic compositions and noble gas isotopic compositions.

Key words: HIMU, spatial distribution, isotope, genetic model