Real-time Detection of Earthquake Swarms at Redoubt Volcano, 2009

Alarm systems can play a critical role in alerting scientists to anomalous seismicity such as earthquake swarms and volcanic tremor that often precedes or coincides with explosive volcanic eruptions or dome failures. By reducing the need for visual data monitoring, a reliable alarm system can also be a cost effective way to monitor seismicity and minimize fatigue of volcano observatory staff during a prolonged period of volcanic unrest. Recognizing this we designed and implemented a real-time earthquake swarm alarm system capable of identifying the start of, escalations during, and end of a swarm. This system was used to monitor seismicity throughout the 2009 eruption of Redoubt volcano.