Apparently earthquakes are common in northern Chile--one struck just last June that left 12 people dead and destroyed many homes.
Meanwhile, I thought it might be interesting to comment (since that's what I'm here for, I suppose ;-) ) that if I'm not mistaken, Bolivia has no natural coastline and there have been tensions between the two countries recently (in the past several months) about Bolivia's access to Chile's coastline. Just a little connection there--hopefully it won't have any implications.