According to a study by the Geological Institute of ETH Zurich, unusual structures are found deep beneath the Pacific Ocean.
These anomalies were observed using seismic waves generated by earthquakes, reports the media outlet Sciencepost. In certain areas beneath the Pacific Ocean, researchers observed that these waves slowed down in strange and unexpected ways, suggesting the presence of colder structures or those with a different composition than their molten rocky surroundings. These anomalies, hidden in the Earth's lower mantle, remain unexplained for the time being.
As Sciencepost reports, the unusual formations identified in the Earth's mantle are generally thought to be tectonic plates sinking very slowly into the depths. However, beneath the Pacific Ocean, this explanation doesn't seem to hold water: a single tectonic plate supports this region. This could disrupt conventional understandings of the dynamics of the Earth's mantle.
Ancient remains? Accumulations of rock?
According to researchers at the Geological Institute of ETH Zurich, several hypotheses can be put forward: these anomalies could be ancient remains dating back to the Earth's formation, nearly 4 billion years ago, which have survived the internal changes our planet has undergone. Another possibility is that these structures are the result of accumulations of particularly iron-rich rocks, formed following the evolution of the Earth's mantle.
"We thought we understood the Earth's mantle, but these discoveries show that we still have a huge amount to learn," emphasizes Thomas Schouten, lead author of the study and a doctoral student at ETH Zurich.
The dynamics of the Earth's mantle could be much more complex than scientists previously thought. With only a single factor to analyze—wave speed variations that can deduce the composition and density of materials located deep within—researchers are still unable to dispel doubts about these strange structures.
(MH with Raphaël Liset - Source : Sciencepost - Illustration : ©Unsplash)
Quick links