University of Utah Seismograph Stations.
The Wasatch Plateau-Book Cliffs coal-mining area of central-eastern Utah is shown in this map. Epicenters of "seismic events" during almost 30 years are shown as red circles and yellow stars. Of the total 17,417 events, about 98 percent were induced by mining and less than 2 percent were natural earthquakes. One of the larger events, marked "August 6, 2007," was the tragic collapse in the Crandall Canyon Mine, which led to the deaths of six miners and three rescuers.