Lava from different parts of the world may actually come from the same source deep within the Earth’s mantle, according to a new study. This challenges previous beliefs that the mantle was a mix of different rock compositions. The study suggests that the mantle is more uniform and well-mixed than scientists previously thought, similar to a blended smoothie rather than a stew.
The research focused on hotspot lavas, which come from plumes rising from the Earth’s deep mantle and erupting at volcanoes on the surface. Despite variations in trace elements in these lavas, the study found that they all share a similar starting composition. This indicates that the differences in lavas from different hotspots are due to changes as they rise through the upper mantle and crust, rather than originating from different reservoirs of rock.
The study looked at concentrations of nickel, niobium, and chromium in hotspot lavas to determine how much they had changed from their original source in the mantle. The results showed that the lavas with the least amount of changes had major similarities in composition, pointing to a common starting composition for hotspot lavas worldwide.
This new understanding of the mantle challenges previous theories about structures in the deep mantle, such as large low-shear velocity provinces (LLVPs), which were thought to be remnants of ancient space rocks or material from Earth’s crust. The study suggests that these structures may have the same composition as the rest of the mantle, with differences in temperature being the only significant factor.
Overall, the study reveals a simpler and more uniform picture of the Earth’s mantle than previously believed. This new insight could reshape our understanding of how the mantle and crust interact and may eliminate the need for complex explanations about unmixed pockets of rock within the mantle.
Stephanie Pappas, a contributing writer for Live Science, provided this information. She covers a wide range of topics, including geoscience, archaeology, and human behavior. Her background in psychology and science communication gives her a unique perspective on scientific discoveries. Stephanie’s work has been featured in various publications, highlighting her expertise in translating complex scientific concepts for a broader audience.
