"No one saw it happen, but a crack 50' wide and 6 football fields long has opened in Wyoming..."

No one saw it happen, but a crack 50' wide and 6 football fields long has opened in Wyoming https://t.co/IPfMmtQvju pic.twitter.com/i0SZSeQcfd

— 9NEWS Denver (@9NEWS) October 30, 2015

WaPo quotes some "experts" "allay[ing the] fears" of social media folk who are speculating about volcanoes and earthquakes.