Fatal mine collapse covered 50 acres

This map shows the part of the Crandall Canyon Mine that was being mined in August 2007, when a collapse occurred. A smaller collapse in March 2007 (red rectangle marked "March Damage") forced coal miners out of the north barrier pillar. Mining later resumed in the south part of the mine. The solid red rectangle marked "Aug. 6 Collapse" represents the Mine Safety and Health Administration's original estimate of how much of the mine collapsed. A new study by University of Utah seismologists concludes the collapse covered an area four times larger, or 50 acres, represented by red-dashed rectangle. The new study also concludes the mine collapse's "hypocenter" -- the underground point (red star) where a seismic event begins -- was located very near where miners were working at the time of the collapse and near areas that had been mined during July and early August. Credit: University of Utah Seismograph Stations