Sanukitoid stable isotopes reveal complex crust-mantle dynamics in the early Earth
Abstract The Archean to Paleoproterozoic Earth underwent significant changes in surface, crust and mantle systems, yet interactions between these reservoirs remain poorly constrained. Sanukitoids are generated by mantle–crust interaction, and thus provide a record of early Earth recycling processes. Here we combine Barium (Ba) and Magnesium (Mg) stable isotopes with radiogenic isotopes and elemental data from 3.4-2.1 Ga sanukitoids to trace crust-mantle interaction across this critical interval. Archean sanukitoids display highly variable Ba and Mg isotopic compositions, suggesting contributions from altered ocean crust, hydrothermal barite and/or sediment. In contrast, Paleoproterozoic sanukitoids show uniformly lighter isotopic signatures, closely resembling Phanerozoic arc magmas influenced by pelagic sediments. Importantly, Ba isotope fractionation before the Great Oxidation Event indicates local sulfate production and oxidized conditions in sanukitoid sources. These results reveal variable recycling of locally-oxidized ocean crust since the Paleoarchean, and confirm sanukitoids as a key archive of early Earth crust-mantle dynamics.
Authors
- C. Storey
- Henrique Bruno (ORCID: https://orcid.org/0000-0003-3863-6576)
- Kumar Batuk Joshi (ORCID: https://orcid.org/0000-0002-6949-7778)
- Marc‐Alban Millet (ORCID: https://orcid.org/0000-0003-2710-5374)
- Laura Spencer
- Mike Fowler
- Hugo Moreira (ORCID: https://orcid.org/0000-0001-5910-3731)
- Ren-Zhi Zhu (ORCID: https://orcid.org/0000-0001-5433-9585)
- Guochun Zhao (ORCID: https://orcid.org/0000-0002-5429-0758)
- Xiaoping Long (ORCID: https://orcid.org/0000-0003-0996-196X)
- Fang Huang (ORCID: https://orcid.org/0000-0003-1885-3311)
- Jiyuan Yin (ORCID: https://orcid.org/0000-0003-3554-7674)
- Robert H. Smithies (ORCID: https://orcid.org/0000-0003-1878-597X)
- Shaocong Lai
Institutions
- University of Science and Technology of China (CN)
- Geological Survey of Western Australia (AU)
- Central University of Himachal Pradesh (IN)
- Chinese Academy of Geological Sciences (CN)
- Universidade do Estado do Rio de Janeiro (BR)
- Continental (United Kingdom) (GB)
- University of Portsmouth (GB)
- Cardiff University (GB)
- University of Hong Kong (HK)
Publication Details
- Journal
- Communications Earth & Environment
- Published
- 2026-05-30
- DOI
- https://doi.org/10.1038/s43247-026-03700-y
- Primary Topic
- Geological and Geochemical Analysis
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Natural Science Foundation of China
- National Science and Technology Major Project
- Chinese Academy of Geological Sciences