The Earth’s mantle is currently divided into the African and Pacific domains, separated by the circum-Pacific subduction girdle, and each domain features a large low shear-wave velocity province (LLSVP) in the lower mantle. However, it remains controversial as to whether the LLSVPs have been stationary through time or dynamic, changing in response to changes in global subduction geometry. Here we compile radiogenic isotope data on plume-induced basalts from ocean islands and oceanic plateaus above the two LLSVPs that show distinct lead, neodymium and strontium isotopic compositions for the two mantle domains. The African domain shows enrichment by subducted continental material during the assembly and breakup of the supercontinent Pangaea, whereas no such feature is found in the Pacific domain. This deep-mantle geochemical dichotomy reflects the different evolutionary histories of the two domains during the Rodinia and Pangaea supercontinent cycles and thus supports a dynamic relationship between plate tectonics and deep-mantle structures.

目前，地球的地幔分为非洲和太平洋地区，由环太平洋俯冲带隔开，每个地区在下地幔中都有一个较大的低剪切波速度省（LLSVP）。然而，关于LLSVP是否随时间静止还是随着时间变化而动态变化仍然是有争议的，它是根据整体俯冲几何形状的变化而变化的。在这里，我们收集了来自两个LLSVP之上的大洋岛屿和海洋高原的羽状玄武岩的放射同位素数据，这些玄武岩显示出两个地幔域的铅，钕和锶同位素组成不同。在超大陆Pangaea的组装和破裂过程中，非洲地区显示出俯冲大陆物质的富集，而在太平洋地区则没有发现这种特征。