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大多数OIB源区都含有经俯冲作用或其他过程再循环进入地幔的地壳组分。早期研究一般认为再循环地壳组分为MORB,经过海底热液蚀变及俯冲作用后具有高U/Pb值,最终进入OIB源区形成具极端放射性成因Pb同位素组成特征(206Pb/204Pb>20)的HIMU型OIB。但是用俯冲MORB型洋壳来解释HIMU的地球化学特征受到了越来越多的质疑。
Most OIB source areas contain crustal components recycled into the mantle by subduction or other processes. Earlier studies suggested that the recirculated crustal component is MORB and possesses high U / Pb value after seafloor hydrothermal alteration and subduction, finally entering the OIB source region to form Pb isotopic composition with extreme radiogenic origin (206Pb / 204Pb> 20) HIMU type OIB. However, the subduction of MORB-type oceanic crust to interpret the geochemical characteristics of HIMU has been more and more questioned.