Everest Isn’t Earth’s Tallest Mountain Anymore: Scientists Uncover Hidden Mega-Structures 100X Taller and Billions of Years Old

Key Points:

• Researchers at Utrecht University used normal-mode seismology to create a detailed 3D model (QS4L3) of Earth's mantle, revealing two colossal structures called Large Low Shear Velocity Provinces (LLSVPs) rising about 1,000 km from the core-mantle boundary beneath Africa and the central Pacific.
• These LLSVPs, spanning up to 5,000 km across, are thermochemical structures distinguished by low seismic attenuation and velocity, suggesting they have a unique composition with larger mineral grains and are not merely hotter regions.
• The study supports the theory that LLSVPs are ancient subducted oceanic slabs that have persisted for billions of years at the core-mantle boundary, resisting mixing due to their distinct chemistry and influencing mantle convection.
• The LLSVPs act as stable anchors beneath the Earth’s surface, affecting tectonic plate movements and feeding volcanic hotspots like Hawaii and Iceland through mantle plumes rising from their summits.
• This breakthrough in seismic attenuation measurement across the entire mantle provides new insights into the deep Earth’s structure and dynamics, highlighting the existence of the tallest "mountains" on Earth far below the surface.