A "quick" slow motion clip illustrates how a seismograph measures the vertical motion of S and P waves. [0:13]

Two animated GIFs of a reverse fault and station seismogram teachers can use for a presentation.

See how travel-time curves are created. [2:52]

Scientists have developed far-more sensitive seismometers that, with faster computers, have enabled them to record & interpret a broader spectrum of seismic signals than was possible in the 1930's, when the Richter magnitude was...

In this animation take a look at two magnitude scales, and use two examples of magnitude changing. [6:54]