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> In other words, mantle plumes are parts of the mantle that are hotter than the other identically composed mantle around them. The parent's link suggests that
by valarauko 4y ago
> In other words, mantle plumes are parts of the mantle that are hotter than the other identically composed mantle around them.
The parent's link suggests that alternate views exist, that the mantle plumes are indeed chemically distinct from the surrounding rock.
From the linked article:
This suggests that the edges of the blobs mark a transition between materials, not just temperature.
In this view, the blobs are so-called thermochemical piles, clumps of dense rock with a distinct chemical composition. Because of their prolonged contact with the core, they are hotter than the rest of the mantle, causing plumes to sprout.
- jofer 4y agoYes, there's a chemical component as well. I was simplifying. Regardless, though, they're not core material rising up. They're still basically olivine+pyroxenes+etc, same as what's around them. They're not the exact same, and indeed they bring deep mantle material up, but they're not nickle-iron rising up from the outer core, which is what I was trying to get across.