The Cascadia Earthquake.
<p>The original uploader was <a href="https://en.wikipedia.org/wiki/User:Arg" class="extiw" title="wikipedia:User:Arg">Arg</a> at <a href="https://en.wikipedia.org/wiki/" class="extiw" title="wikipedia:">English Wikipedia</a>..
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Later versions were uploaded by <a href="https://en.wikipedia.org/wiki/User:Remember_the_dot" class="extiw" title="en:User:Remember the dot">Remember the dot</a> at <a class="external text" href="https://en.wikipedia.org">en.wikipedia</a>.
18 July 2007 (original upload date)
<a rel="nofollow" class="external free" href="https://geomaps.wr.usgs.gov/pacnw/pacnweq/pdf/subd_eqpg.pdf">https://geomaps.wr.usgs.gov/pacnw/pacnweq/pdf/subd_eqpg.pdf</a>