Annotated 24-hour webicorder display for station CKN at Mount Spurr Volcano on September 10, 2014. During a daily check of seismic data as the AVO duty seismologist, AVO geophysicist John Lyons noted the protracted, sudden onset signal that occurred just after 11:21 local time. He interpreted this as a likely outburst of water from beneath one of the glaciers that flow southward off Mount Spurr. AVO seismologists have seen other examples of this type of long-duration signal when high-discharge events have been seen in the field. Note how different this appears from a typical regional earthquake (at top) and the twice-daily station calibration pulses (at left). Figure by John Lyons, USGS/AVO.
Volcano(es): Spurr
Photographer: Lyons, John
URL: avo.alaska.edu/image/view/67731
Spurr 2014/6
From Cameron and others, 2017: "A swarm of low-frequency earthquakes began in early June, following a M3.8 earthquake 13 km (8 mi) west of Mount Spurr. A total of 300 earthquakes were located in this swarm, which ended in mid-October. A swarm in the same area occurred in late 2012. The cause of the swarm remains undetermined. In 2004, seismicity, surface heat flux, and gas emissions suggested a magmatic intrusion (Power, 2004; Neal and others, 2005; Coombs and others, 2006).
"At 20:20 UTC (11:20 a.m. AKDT) on September 10, the Spurr seismograph network recorded a signal interpreted by AVO seismologists as a glacial outburst flood. The flow appears as a single event lasting about 20 minutes. Similar events, but of longer duration, have been recorded at Mount Spurr on several occasions, most recently in 2012 (Herrick and others, 2014). AVO was unable to visually confirm the inferred outburst event."
Use Restriction: Please cite the photographer and the Alaska Volcano Observatory / U.S. Geological Survey when using this image.
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