[Rockhounds] 2.5 Billion-Year-Old “Time Capsule” Rocks Rewrite History: New Study Challenges Mantle Oxidation Theory

[Kreigh Tomaszewski]

Researchers at the Smithsonian’s National Museum of Natural History
<https://scitechdaily.com/tag/smithsonian/> have conducted a new analysis
of rocks believed to be at least 2.5 billion years old, shedding light on
the chemical history of Earth’s mantle, the layer beneath the planet’s
crust. Their findings enhance our understanding of Earth’s earliest
geologic processes and contribute to a long-standing scientific debate
regarding the planet’s geologic history. Notably, the study provides
evidence that the oxidation state of most of Earth’s mantle has remained
stable over geological time, challenging previous assertions by other
researchers about major transitions.

“This study tells us more about how this special place in which we live
came to be the way it is, with its unique surface and interior that have
allowed life and liquid water to exist,” said Elizabeth Cottrell, chair of
the museum’s department of mineral sciences, curator of the National Rock
Collection and co-author of the study. “It’s part of our story as humans
because our origins all trace back to how Earth formed and how it has
evolved.”
https://scitechdaily.com/2-5-billion-year-old-time-capsule-rocks-rewrite-history-new-study-challenges-mantle-oxidation-theory/