LSIB helicorder trace from the Lassen Volcanic Center on June 24, 2024.

This digital helicorder record from station LSIB on the Northern California Seismic Network emphasizes the dozens of tiny earthquakes in Lassen's June 24 swarm. Earch line of the helicorder shows 15 minutes of time, with the entire record covering 24 hours. Red colors indicate maxed-out amplitudes because of proximity or shallowness of earthquakes, while blue and black colors are only used to distinguish alternating lines.