'4 billion-year secret': Earth’s mantle hides ancient tectonic puzzle
Produced by: Mohsin Shaikh
Mantle Mystery
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.
Anomalous Zones
Ancient tectonic plate-like structures, far from subduction sites, suggest mantle dynamics are more complex than previously believed, says lead author Thomas Schouten.
Imaging Breakthrough
Using full-waveform inversion, researchers mapped the mantle with unprecedented detail, finding anomalies undetectable by older seismic models.
Material Origins
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.
Global Patchwork
These anomalies suggest the mantle may be a patchwork of diverse materials, challenging long-held assumptions about its uniformity.
Comparative Limitations
While seismic waves reveal the speed of mantle structures, their chemical composition and elasticity remain unknown, requiring advanced modeling.
Unexpected Findings
ETH professor Andreas Fichtner compared the discovery to finding arteries in unexpected places, highlighting its transformative implications for geology.
Credit: Daniel Winkler / ETH Zurich
Ancient Clues
If confirmed, these zones could be among the oldest surviving remnants of the Earth’s mantle, offering a rare glimpse into its formative years.
Future Studies
Researchers aim to investigate similar anomalies globally and decode the material properties influencing mantle dynamics, shaping our understanding of Earth’s interior.