Ice piled onto a landmass presses it down into the squishy mantle layer below Earth's crust. (discovermagazine.com)
• Sticky problem: Earth's mantle layer flows slowly but is solid (2 September, p 40). (newscientist.com)
For instance, oceanic crust loaded with carbon - rich sediment could delve, or subduct, to mix with the upper mantle layer of hot rock that reaches about 410 miles (660 kilometers) down, or even to the lower mantle below that. (scientificamerican.com)