Photo credit: www.gadgets360.com
A recent study featured in the journal Nature indicates that the formation of a magma ocean near Earth’s core commenced approximately 4.4 billion years ago. This early geological phenomenon may still influence contemporary Earth through unusual mantle anomalies. The findings suggest that a basal magma, likely situated at the boundary between the mantle and the core, has played a pivotal role in elucidating the structure of the mantle, including the Large Low-Velocity Provinces (LLVPS), identified through seismic imaging techniques. This historical formation has significantly shaped Earth’s thermal and tectonic evolution.
Discovery and Implications
Leading the study, Assistant Professor Charles-Édouard Boukaré from York University, Toronto, noted in an interview with Live Science that these ancient magma oceans could influence the thermal dynamics between the mantle and core, thereby affecting the positions of tectonic plates.
The research team has introduced a new model that amalgamates geochemical and seismic data, facilitating an understanding of how early crystallization processes contributed to the enduring molten layer deep within the Earth. Boukaré, along with James Badro and Henri Samuel, affiliated with French research institutions, made significant contributions to this study published in Nature.
Formation of Basal Magma Ocean
The researchers concluded that the emergence of a magma ocean was unavoidable, regardless of whether the Earth’s mantle solidified from core to surface or vice versa. In both scenarios, their model suggests that denser iron oxide-rich solids would subside near the Earth’s core, melting again due to the extreme temperature and pressure, which would result in a permanent molten layer. Boukaré highlighted that the formation of a basal melt is likely even under the least favorable conditions.
Lasting Effects and Geological Memory
This investigation reveals that the ancient magma ocean has left an enduring mark on the Earth’s interior, a memory that has persisted for hundreds of millions of years. Boukaré pointed out that the internals of Earth were defined very early in its history and continue to significantly affect geological processes, including tectonic shifts and mantle convection. The LLVPS, dating back around 4.4 billion years, may represent remnants of this ancient primordial layer.
Looking to Other Planets
Boukaré plans to extend the research model by incorporating additional trace elements and applying it to rocky planets beyond Earth. He posits that the event of a basal magma ocean might not be exclusive to our planet, suggesting that this research could significantly enhance our understanding of planetary formation throughout the solar system.
Source
www.gadgets360.com