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Ancient Rocks Reveal Rare Traces of Proto Earth

10/19/2025

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Summary

Story summary

Massachusetts Institute of Technology researchers have found rare traces of proto Earth dating to 4.5 billion years ago in ancient rocks.
The findings, published in Nature Geosciences, reveal an unusual potassium isotope imbalance in those rocks.
The researchers say the anomaly cannot be explained by known geological processes and may be the first direct evidence of preserved proto Earth materials, prompting further study.

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Story summary

Massachusetts Institute of Technology researchers have found rare traces of proto Earth dating to 4.5 billion years ago in ancient rocks.
The findings, published in Nature Geosciences, reveal an unusual potassium isotope imbalance in those rocks.
The researchers say the anomaly cannot be explained by known geological processes and may be the first direct evidence of preserved proto Earth materials, prompting further study.