In a groundbreaking study published in Nature Geoscience, Dr. Qian Yuan, Assistant Professor in Texas A&M’s Department of Geology & Geophysics and Principal Investigator of the Intelligent Modeling of Planetary Accretion, Convection, and Tectonics (IMPACT) Lab, has helped uncover a new explanation for some of the most enigmatic features of Earth’s deep interior.
Working with Dr. Jie Deng at Princeton University, the project lead, along with Dr. Yoshinori Miyazaki at Rutgers University, Yuan and his collaborators have developed a model that sheds light on the origins of Large Low-Velocity Provinces (LLVPs) and Ultra-Low Velocity Zones (ULVZs)—vast, anomalous regions at the base of the mantle that have long puzzled geoscientists.
Their model, called the Basal Exsolution Contaminated Magma Ocean (BECMO), proposes that during Earth’s early evolution, a deep magma ocean at the core-mantle boundary was continuously infused with materials exsolved from the core, such as silicon and magnesium oxide. These contaminants altered the way the magma ocean crystallized, suppressing the formation of dense minerals and instead producing lighter silicate phases.
The process results in a mantle structure that naturally gives rise to LLVPs and ULVZs, regions with distinct seismic and geochemical signatures that may also be the source of prominent volcanic hotspots (e.g., Hawaii). The BECMO model not only aligns with seismic observations but also explains the isotopic fingerprints found in ocean island basalts (OIBs), linking them to deep, primordial reservoirs.
Dr. Yuan’s contribution to this study helps bridge critical gaps in our understanding of mantle dynamics and Earth’s formative processes. By integrating core-mantle interactions into models of early Earth, the research offers a unified mechanism for the formation of deep mantle heterogeneities—one that could reshape how scientists think about the planet’s interior and its long-term evolution.
This research was supported by the National Science Foundation’s Division of Earth Sciences (EAR‐2330810) and Texas A&M start-up funds.