Produced by: Mohsin Shaikh
Hidden zones in the Earth’s mantle, uncovered by seismic imaging, defy geological theories, revealing remnants of unknown processes, according to ETH Zurich and Caltech researchers.
Ancient tectonic plate-like structures, far from subduction sites, suggest mantle dynamics are more complex than previously believed, says lead author Thomas Schouten.
Using full-waveform inversion, researchers mapped the mantle with unprecedented detail, finding anomalies undetectable by older seismic models.
The anomalies could be ancient silica-rich remnants from 4 billion years ago or iron-rich rock accumulations formed by billions of years of mantle convection.
These anomalies suggest the mantle may be a patchwork of diverse materials, challenging long-held assumptions about its uniformity.
While seismic waves reveal the speed of mantle structures, their chemical composition and elasticity remain unknown, requiring advanced modeling.
ETH professor Andreas Fichtner compared the discovery to finding arteries in unexpected places, highlighting its transformative implications for geology.
Credit: Daniel Winkler / ETH Zurich
If confirmed, these zones could be among the oldest surviving remnants of the Earth’s mantle, offering a rare glimpse into its formative years.
Researchers aim to investigate similar anomalies globally and decode the material properties influencing mantle dynamics, shaping our understanding of Earth’s interior.