“Small moves Ellie, small moves.” is more than a famous quote from the motion picture ‘Contact’, it is also an important mantra for many Scientists. In geophysics, a small increase/decrease in the value of a measurement may easily influence an interpretation…. or “miss”- interpretation. See the image below…. this graphic illustrates how “small moves” in frequency can yield different interpretations of seismic waves. Detecting ground motion from the ocean tides, for example, requires instrumentation which can measure very low frequencies; conversely, detecting the ground motion from the sound of fireworks requires a seismograph that can detect very high frequencies. When we observe ground motion recorded on a seismograph, illustrations can help us begin to interpret the data. Image is courtesy of Peter Bormann, Klaus Klinge and Siegfried Wendt.