A seismologist was a scientist who studied earthquakes.
Professor Katsoudas and Nikos Spiridakis were seismologists. Katsoudas claimed to have the ability to predict earthquakes, but in reality he was the one causing them. (PROSE: The Seismologist's Story)
The Spy Master kidnapped and shrunk dozens of seismologists with his Tissue Compression Eliminator. (TV: The Power of the Doctor)