Deep beneath Earth’s surface, in the mantle, lie two giant blobs. These large structures, called the “large low-shear-velocity provinces” and “ultra-low-velocity zones,” are around 1,800 miles down and could help explain how life began on our planet.
Scientists can’t get to these blobs directly, but they study them by measuring seismic waves that travel through Earth. When these waves pass through the blobs, they slow down, suggesting that the blobs have different materials compared to the surrounding mantle. This intriguing discovery suggests that these formations aren’t just random formations—they can tell us a lot about Earth’s early history.
Yoshinori Miyazaki, a geodynamicist at Rutgers University, leads the research on these structures. He believes these blobs may be remnants from Earth’s beginnings, formed billions of years ago when the planet was still a molten mass. As the planet cooled, distinct layers were supposed to form in the mantle, but these blobs indicate something different occurred.
Miyazaki and his team propose that if silicon and magnesium leaked from the core into the mantle, this mix created uneven cooling, leading to the blob structures we see today. This could provide key insights into why Earth became capable of supporting life. Their research indicates that understanding these core-mantle interactions can illuminate how Earth cooled, its volcanic activity, and the development of our atmosphere.
Jie Deng, another researcher from Princeton University, highlights the importance of combining various fields to unravel Earth’s mysteries. He points out that these deep mantle structures may hold chemical clues about previous interactions in Earth’s core, leading to new insights about our planet’s unique evolution.
A recent study published in Nature Geoscience dives deeper into these findings, showcasing the relevance of this work in understanding the history of our planet. This ongoing exploration is not just about looking back; it’s also about understanding how these ancient processes have shaped the world we live in today.
