Possible solar noble-gas component in Hawaiian basalts

M. Honda; I. McDougall; D.B. Patterson; A. Doulgeris; D.A. Clague

doi:10.1038/349149a0

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Possible solar noble-gas component in Hawaiian basalts

M. Honda·I. McDougall·D.B. Patterson·A. Doulgeris·D.A. Clague

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Abstract

The noble-gas elemental and isotopic composition in the Earth is significantly different from that of the present atmosphere, and provides an important clue to the origin and history of the Earth and its atmosphere. Possible candidates for the noble-gas composition of the primordial Earth include a solar-like component, a planetary-like component (as observed in primitive meteorites) and a component similar in composition to the present atmosphere. In an attempt to identify the contributions of such components, we have measured isotope ratios of helium and neon in fresh basaltic glasses dredged from Loihi seamount and the East Rift Zone of Kilauea 1–3 . We find a systematic enrichment in 20 Ne and 21 Ne relative to 22 Ne, compared with atmospheric neon. The helium and neon isotope signatures observed in our samples can be explained by mixing of solar, present atmospheric, radiogenic and nucleogenic components. These data suggest that the noble-gas isotopic composition of the mantle source of the Hawaiian plume is different from that of the present atmosphere, and that it includes a significant solar-like component. We infer that this component was acquired during the formation of the Earth.

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Source-reported bounding extent: 18.917466° to 22.23317° latitude; -160.24961° to -154.809379° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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M. Honda, I. McDougall, D.B. Patterson, A. Doulgeris, D.A. Clague. 1991. Possible solar noble-gas component in Hawaiian basalts. https://doi.org/10.1038/349149a0

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