I wasn't aware that Idaho had a bunch of Volcanoes forming an arc to the south of the Epicenter.
Also of huge note. Large Eq often have after shocks, but these usually spread out in all directions, or at least a few directions on a fault line.
This EQ was unusual.....all the after shocks were off to one side, indicating this movement was all one way. I am thinking a big piece of mantle dropped off and down.
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