Recent Study Reveals the Role of Water in Earth’s Core Formation
A recent study published in the journal Nature Geoscience has shed new light on the formation of a thin layer around the molten metal of the Earth’s outer core. For decades, the origin of this layer has remained uncertain, but researchers now believe that the presence of water on the surface has played a crucial role in its differentiation.
According to the study, water from the Earth’s surface is carried down by descending tectonic plates, eventually reaching the core after a journey of 2,900 kilometers (1,800 miles). Over billions of years, this process has led to the alteration of the edge between the bottom of the mantle and the top of the core, resulting in the formation of a hydrogen-rich silicate-depleted layer.
The alteration scenario suggests that this modified layer of liquid metal undergoes reactions that create silica crystals, which then move into the mantle. This process also results in the layer being less dense with lower seismic velocity, as observed by geologists.
Dr. Dan Shim of Arizona State University, a co-author of the study, explained, “For years, it has been believed that material exchange between Earth’s core and mantle is small. Yet, our recent high-pressure experiments reveal a different story. We found that when water reaches the core-mantle boundary, it reacts with silicon in the core, forming silica.”
The study’s findings point to a far more dynamic interaction between the Earth’s core and mantle than previously thought, suggesting substantial material exchange. This discovery has significant implications for our understanding of the deep interior of our planet.
The study’s lead author, Dr. Margaret Smith, emphasized the importance of more precise seismic data collected from earthquakes and better simulations in revealing new details of the Earth’s interior. She also highlighted the recent discovery of evidence that two regions around the core were remnants of the planetary collision that formed the Moon.
The study’s findings provide valuable insights into the role of water in the formation and evolution of the Earth’s core. With further research and advancements in seismic analysis and simulation, scientists hope to continue unraveling the mysteries of the deep interior of our planet.