It could be from the crust/hardcore punk band Tragedy. They are
from Portland, Oregon. I have seen that logo on one of their
stickers.
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Continental crust.
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The Oceanic crust is denser than the continental crust
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There are two types of crust, and they are the oceanic crust and
the continental crust. Oceanic crust is thinner yet more dense than
continental crust, and continental crust is on average older than
oceanic crust :)