Earth’s Mantle Holds Surprising Secrets: New Study Reveals Widespread Presence of Ultra-Low Velocity Zones
Scientists have long been fascinated by the Earth’s mantle, a vast and mysterious region beneath our feet. A new study published in AGU Advances has shed light on a peculiar phenomenon within the mantle, known as ultra-low velocity zones (ULVZs). These enigmatic features, characterized by a significant slowdown of seismic waves, have been found to be more common than previously thought.
ULVZs are located in the lower mantle, near the boundary with the Earth’s core. Initially linked to volcanic hotspots, such as Hawaii, researchers have discovered that these zones might be widespread, extending across large areas of the mantle. The study, led by geologist Michael Thorne, used data from deep earthquakes to model seismic wave travel and identified patterns indicative of slow-down zones beyond previously known locations.
The research focused on powerful quakes, which travel through various layers of the Earth, including the core and mantle. Precursor PKP waves, which arrive before the main seismic waves, were found to scatter off unknown features in the mantle, leading to the discovery of potential ULVZs in regions such as North America, North Africa, and Papua New Guinea.
Theories suggest that ULVZs might be remnants from ancient meteor impacts or actively formed today. Thorne speculates that these zones could result from mid-ocean basalt, formed at seafloor spreading ridges, which melts and creates pockets when subducted into the mantle. These pockets might then be redistributed by tectonic activity, contributing to the widespread nature of ULVZs.
Understanding ULVZs could enhance our knowledge of volcanic hotspots and mantle dynamics. While the study has made significant progress, many questions remain unanswered. As researchers continue to explore these mysterious features, they hope to uncover more about the processes shaping our planet’s interior.
This groundbreaking research has the potential to revolutionize our understanding of the Earth’s mantle and its complex dynamics. As scientists continue to delve deeper into the mysteries of ULVZs, we may uncover new insights into the Earth’s history and the processes that shape our planet.
