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

ABSTRACT: Rare high-³He/⁴He signatures in ocean island basalts (OIB) erupted at volcanic hotspots derive from deep-seated domains preserved in Earth's interior. Only high-³He/⁴He OIB exhibit anomalous ¹⁸²W-an isotopic signature inherited during the earliest history of Earth-supporting an ancient origin of high ³He/⁴He. However, it is not understood why some OIB host anomalous ¹⁸²W while others do not. We provide geochemical data for the highest-³He/⁴He lavas from Iceland (up to 42.9 times atmospheric) with anomalous ¹⁸²W and examine how Sr-Nd-Hf-Pb isotopic variations-useful for tracing subducted, recycled crust-relate to high ³He/⁴He and anomalous ^182</

SUBMITTER: Jackson MG 

PROVIDER: S-EPMC7733831 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature