mantle

The scientists based their analysis on a theoretical framework they recently proposed called 'mantle wave' theory, which was named a finalist for Science magazine's 2024 Breakthrough of the Year.

As Earth's metallic core formed, elements such as iron and molybdenum migrated inward and became concentrated there, leaving the mantle with much lower amounts.

Both strongly slow seismic waves, suggesting they contain materials or conditions unlike the surrounding mantle.

Some volcanic regions lack evidence of recycled crust, while others seem too shallow and cool to be driven by deep mantle plumes.

Rock from the subducting plates turns to magma when it reaches the mantle, creating hot spots that, over millennia, melt through the crust and break through as lava, forming volcanoes.