Ancient helium and tungsten isotopic signatures preserved in mantle domains least modified by crustal recycling

This is the authors' abstract. We don't add key points for this paper.

Significance The recent discovery of anomalous 182 W signatures in modern, plume-derived hotspot lavas provides evidence for survival of domains in Earth’s interior since the early Hadean. Only lavas with ancient, high- 3 He/ 4 He signatures preserve anomalous 182 W signatures. However, it is not known why only high- 3 He/ 4 He lavas have anomalous 182 W, while other hotspot lavas do not. We show that only hotspot lavas lacking strong recycled crust signatures exhibit high 3 He/ 4 He and anomalous 182 W. This observation is explained by subduction of W- and 4 He-rich crust that has low 3 He/ 4 He and normal 182 W: Following subduction, the crust masks high- 3 He/ 4 He and anomalous 182 W signatures characteristic of ancient mantle domains. Our model links destruction of Hadean geochemical signatures with the geodynamic process of plate subduction and recycling.