Researchers at the Hebrew University have made a significant breakthrough in understanding the Earth’s mantle, revealing the first natural evidence of nickel-rich alloys located beneath 300 kilometers deep. Led by Yaakov Weiss and his colleague Yael Kempe, this study sheds light on the planet’s redox landscape and its implications for volcanic activity.
The research team utilized diamonds from South Africa’s Voorspoed mine, which contain minute inclusions that provide valuable insights into the mantle’s characteristics. Weiss emphasized just how important these discoveries are. They give us an incredible glimpse into the complex chemical reactions taking place far beneath the Earth’s surface.
Unveiling the Earth’s Redox Landscape
Yaakov Weiss, a prominent researcher at the Hebrew University’s Institute of Earth Sciences, has dedicated his work to understanding the characteristics of the Earth’s mantle, particularly focusing on its redox state. His latest study is a big step forward in this effort. It bottom lines the fact that preferential oxidation of iron over nickel enriches residual alloys with nickel.
This study provides strong support for the importance of melt-rock interactions in influencing the course of the Earth’s redox landscape. Weiss and Kempe joined forces to take a more comprehensive look. Notably, they observed the presence of nickel-rich alloys and explored the mechanisms behind their formation.
“This is a rare snapshot of mantle chemistry in action,” – Yaakov Weiss
Weiss and Kempe went on a detective hunt and made a thrilling find. In doing so, they discovered that nickel-rich alloys are key to producing volatile-rich magmas. Learning about these processes is ideally a prerequisite. That understanding gives us insight into the formation of a variety of volcanic rock types, including kimberlites, lamprophyres, and ocean island basalts.
Diamonds as Time Capsules
These specific diamonds analyzed in this study make for excellent geological time capsules. They lock into place metamorphic reactions that would otherwise be destroyed as minerals equilibrate with their environment. Weiss explained that with these additions, scientists can work backwards to tell the story of key moments in mantle chemistry.
“The diamonds act as tiny time capsules, preserving a reaction that would otherwise vanish as minerals re-equilibrate with their surroundings.” – Yaakov Weiss
These observations highlight the value of using natural samples such as diamonds to gain insight into our planet’s interior. Climate scientists study these nano- and micro-inclusions embedded in these diamonds. This enables them to develop a deeper understanding of the chemical processes in the mantle and their wider relevance for planetary geology.
Implications for Volcanic Activity
This figurative ice-breaking research has significant ramifications for insight into volcanic eruptions and magma creation, among other activities. Our joint experimental and observational study shows compelling links between subduction processes and mantle redox dynamics. It’s these connections that are key to generating volatiles-rich magmas.
Additionally, the information collected by this research project would greatly improve our understanding of how different volcanic systems work and change over time. By linking the oxidation processes occurring deep in the mantle with surface volcanic activity, Weiss and Kempe’s work contributes to a more integrated view of Earth’s geological processes.
Their work, published in the Proceedings of the National Academy of Sciences, has broken ground for future, more detailed studies involving complicated interactions. More specifically they look at both the connections between subduction, mantle dynamics and magmatic evolution.