Primordial neon and the deep mantle origin of kimberlites
The genesis of kimberlites is unclear despite the economic and scientific interest surrounding these diamond-bearing magmas. One critical question is whether they tap ancient, deep mantle domains or the shallow convecting mantle with partial melting triggered by plumes or plate tectonics. To address this question, we report the He-Ne-Ar isotopic compositions of magmatic fluids trapped in olivine from kimberlites worldwide. The kimberlites which have been least affected by addition of deeply subducted or metasomatic components have Ne isotopes less nucleogenic than the upper mantle, hence requiring a deep-mantle origin. This is corroborated by previous evidence of small negative W isotope anomalies and kimberlite location along age-progressive hot-spot tracks. The lack of strong primordial He isotope signatures indicates overprinting by lithospheric and crustal components, which suggests that Ne isotopes are more robust tracers of deep-mantle contributions in intraplate continental magmas. The most geochemically depleted kimberlites may preserve deep remnants of early-Earth heterogeneities.
Authors
- Bradley J. Peters (ORCID: https://orcid.org/0000-0003-2249-6927)
- D. Graham Pearson (ORCID: https://orcid.org/0000-0001-5974-4192)
- Mark D. Kurz (ORCID: https://orcid.org/0000-0003-1745-2356)
- Quentin Charbonnier (ORCID: https://orcid.org/0000-0001-7234-9461)
- Finlay M. Stuart (ORCID: https://orcid.org/0000-0002-6395-7868)
- Janne M. Koornneef (ORCID: https://orcid.org/0000-0003-4090-8315)
- Andrea Giuliani (ORCID: https://orcid.org/0000-0002-6823-2807)
- Peter H. Barry (ORCID: https://orcid.org/0000-0002-6960-1555)
- Senan Oesch (ORCID: https://orcid.org/0000-0002-8187-5866)
- Joshua Curtice
- Kristoffer Szilas (ORCID: https://orcid.org/0000-0002-5541-306X)
Institutions
- University of Copenhagen (DK)
- Planetary Science Institute (US)
- University of Alberta (CA)
- Carnegie Institution for Science (US)
- ETH Zurich (CH)
- Scottish Universities Environmental Research Centre (GB)
- Woods Hole Oceanographic Institution (US)
- Vrije Universiteit Amsterdam (NL)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-04-05
- DOI
- https://doi.org/10.1038/s41467-025-58625-5
- Citations
- 4
- Primary Topic
- Geological and Geochemical Analysis
- Type
- article
- Field-Weighted Citation Impact
- 7.47
Funders
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung