Eli5 why can’t we hear/feel the earth’s magma churning away under our feet always?

Question

The earth is so big, and as I understand, constantly moving and roiling away inside – why isn’t there a constant low level rumble?

In: 6

Answer 1

[The Kola Superdeep Borehole](https://en.wikipedia.org/wiki/Kola_Superdeep_Borehole) is the deepest hole on Earth at 12,262m deep. Still no magma. The crust is very thick relative to a human. It’s very thin relative to the Earth as a whole.