#2058: Rock Wall

XKCD comic, described below.
Transcript

[Ponytail is gesturing towards Megan with her hand, while talking to her.]

Ponytail: I live next to a wall of rock 20 miles thick. There's no way around or over it. I'm trapped on this side forever.

Ponytail: I study the stuff on the other side.

[Caption below the frame:]

Mantle geology seems like the most frustrating field.


(Sourced from explainxkcd.com)

Title text:I don't trust mantle/core geologists because I suspect that, if they ever get a chance to peel away the Earth's crust, they'll do it in a heartbeat.


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