Ever wonder how the Earth "hears" a large mass movement? AVO recorded seismic signals from an approximately 5-mile-long ice and rock avalanche on Iliamna Volcano in June 2019. The ground motion data in this movie are sped up by a factor of 200, turning the normally sub-audible rumbling into a soundtrack humans can hear. The bottom panel shows ground velocity over time, and the top panel shows the corresponding frequency content (i.e., the "pitch" of the sound).