Plot of recorded earthquake activity (≥ M 1.5) at Yellowstone fro...

Plot of recorded earthquake activity (≥ M 1.5) at Yellowstone from 1974 through 2004 (blue bars) along with caldera uplift and subsidence (red dotted line). The green line shows the cumulative number of earthquakes for the thirty-year period (Updated from a figure in Waite and Smith, 2002).