Image attribution: Hugo Moreira / Nature Geoscience
A recent scientific investigation has established a correlation between archaic changes in the Earth’s atmosphere and its mantle’s chemical makeup, thereby contributing new perspectives on planetary evolution.
A global consortium of researchers has revealed a crucial connection between the Earth’s primordial atmosphere and the chemical composition of its deep-seated mantle.
Spearheaded by experts from the University of Portsmouth and the University of Montpellier, the research offers fresh insights into Earth’s biological development and the emergence of atmospheric oxygen.
Table of Contents
Examining the Great Oxidation Event
The researchers scrutinized magmas generated in ancient subduction zones, regions where Earth’s crust re-enters the mantle. They focused on a critical juncture in Earth’s chronology—the Great Oxidation Event (GOE). Occurring approximately between 2.1 and 2.4 billion years ago, this event marked a rapid rise in atmospheric oxygen levels, thereby revolutionizing life forms and terrestrial conditions. However, the impact of such atmospheric transformations on Earth’s mantle has been largely unexplored.
Image attribution: Dr. Hugo Moreira
Plate Tectonics and the Earth’s Mantle
The study, published in Nature Geoscience, investigated the function of plate tectonics—the mechanism causing Earth’s external shell to move and reshape—in transferring elements between the atmosphere, Earth’s surface, and its inner mantle. Prior to this, there were no dependable techniques to decipher these complex interactions.
Upon examining magmas before and after the GOE, the researchers discerned a change from less oxidized to more oxidized magmas. This shift was prompted by the deep subduction of oxidized sediments from eroded mountains, which were subsequently recycled into the mantle. This demonstrates how the recycling of sediments granted the atmosphere access to the mantle.
Image attribution: Dr. Hugo Moreira
The Discovery’s Import
The findings suggest that these ephemeral oxygen increases may have modified the mantle by promoting the oxidation of calc-alkaline magma, altering the constitution of the continental crust, and facilitating the creation of ore deposits on Earth.
Dr. Hugo Moreira, the lead author from the University of Montpellier and visiting scholar at the University of Portsmouth, commented, “These discoveries have dramatically advanced our comprehension of Earth’s early ‘respiration.’ They not only offer vital clues into Earth’s geological metamorphosis but also illuminate the intimate connection between atmospheric variations and the mantle.”
Research Techniques
To perform their analysis, the research team utilized the ID21 beamline at the European Synchrotron Radiation Facility in France. They examined the sulfur states in minerals preserved in two-billion-year-old zircon crystals from the Mineiro Belt in Brazil. Their observations revealed a more oxidized state in minerals post-GOE compared to those pre-GOE.
Image attribution: The European Synchrotron Radiation Facility
Concluding Remarks
Dr. Moreira stated, “Oxygen fugacity in the mantle, plainly speaking, is an index of oxygen’s role in driving chemical reactions in magmas, and is essential for comprehending volcanic activities and ore formations. The study offers a robust framework for understanding the interaction between Earth’s external and internal domains.”
Professor Craig Storey from the University of Portsmouth added, “Our research inaugurates promising new dimensions for study, deepening our grasp of Earth’s archaic history and its vital connection to atmospheric evolution.”
Dr. Moreira concluded, “As the inquiry into Earth’s geological past persists, one thing remains unequivocal: there is much yet to unearth beneath our feet.”
For further details on this research, refer to “Decoding Earth’s Ancient Atmospheric Mysteries.”
Reference: “Sub-arc mantle fugacity shifted by sediment recycling across the Great Oxidation Event” by Hugo Moreira et al., published on 31 August 2023 in Nature Geoscience. DOI: 10.1038/s41561-023-01258-4
The collaborative effort included scholars from the University of Portsmouth, the Universities of Brest and Montpellier in France, the Federal University of Ouro Preto and University of São Paulo in Brazil, as well as the European Synchrotron Radiation Facility.
Frequently Asked Questions (FAQs) about Earth’s mantle chemistry
What is the primary focus of the research conducted by the University of Portsmouth and the University of Montpellier?
The primary focus of the research is to understand the link between Earth’s ancient atmospheric shifts and its mantle’s chemical composition, with particular attention to the Great Oxidation Event and the role of plate tectonics.
Who were the lead researchers in this study?
The study was spearheaded by Dr. Hugo Moreira from the University of Montpellier, who was also a visiting researcher at the University of Portsmouth, and co-authored by Professor Craig Storey, Professor of Geology at the University of Portsmouth.
What is the Great Oxidation Event (GOE), and why is it significant in this study?
The Great Oxidation Event, which occurred approximately 2.1 to 2.4 billion years ago, was a critical juncture in Earth’s history where oxygen levels in the atmosphere increased rapidly. The study investigates how this event impacted the chemistry of Earth’s mantle.
What role do plate tectonics play in the study?
The study examines the role of plate tectonics in the cycling and exchange of elements between Earth’s atmosphere, surface, and deep mantle. It investigates how plate tectonic processes may have allowed atmospheric access to the mantle, particularly during the GOE.
What was the research methodology used?
The research team employed the ID21 beamline at the European Synchrotron Radiation Facility in France to analyze the sulfur states in minerals from two-billion-year-old zircon crystals.
What are the key findings of the study?
The study found that magmas became more oxidized after the Great Oxidation Event due to the deep subduction of oxidized sediments. This discovery implies that ancient atmospheric changes may have had a lasting impact on the Earth’s mantle chemistry and contributed to Earth’s geological evolution.
How does this study contribute to our understanding of Earth’s history?
The study significantly advances our understanding of Earth’s geological and atmospheric evolution by revealing how ancient atmospheric shifts are intimately connected to changes in Earth’s deep mantle. It also opens new avenues for research into the interplay between Earth’s external and internal reservoirs.
What are the implications of the study for the future?
The study lays the foundation for deeper inquiries into Earth’s ancient past and its relationship with atmospheric changes, posing new questions about the evolution of magma types over time and how plate tectonics are intertwined with atmospheric cycles.
Who else was involved in the study?
The study was a collaborative effort that included scholars from the Universities of Brest and Montpellier in France, the Federal University of Ouro Preto and University of São Paulo in Brazil, as well as the European Synchrotron Radiation Facility.
More about Earth’s mantle chemistry
- Nature Geoscience Journal
- University of Portsmouth Research
- University of Montpellier Research
- European Synchrotron Radiation Facility
- Information on the Great Oxidation Event
- Understanding Plate Tectonics
- Federal University of Ouro Preto
- University of São Paulo Research
- Universities of Brest and Sorbonne
6 comments
I gotta say, I’m pretty stoked to see where this study leads. Plate tectonics, atmospherc shifts, and Earth’s mantle… it’s like the Holy Trinity of geology.
Wow, this is groundbreaking! Who woulda thought the air we breath could have such deep connections, like literally into the Earth’s mantle.
The methodolgy seems complex but worth it. Its crazy how they use sulfur state to figure out ancient atmospherc shifts. I’m curious about whats next in this line of research.
Huh, so this could explain why there’s diff types of ore in the Earth? That’s something i hadn’t thought about. Got to dig deeper, no pun intended.
seriously this is some next-level stuff. I mean, we’re talkin billions of years ago and these scientists are putting the pieces together like its a jigsaw.
That Great Oxidation Event sounds like a big deal. Makes u wonder what else changed back then that we still don’t know bout.