|Start:||January 8, 2006 ||Observed|
|Stop:||January 22, 2006 ± 2 Days||Observed|
|Seismicity with no confirmed eruption: ||
|Eruption Type:||Not an eruption.|
From Neal and others (2009): "On January 10, 2006, AVO raised the Level of Concern from GREEN to YELLOW after a sharp increase in earthquake activity beneath Mount Martin that had begun on January 8 (Dixon and others, 2007). Roughly 300 earthquakes were located in just over 2 days [see fig. 38 in original text], a significant increase over the long-term average rate of less than one event per day since the seismic network was installed in 1996. Satellite data did not indicate any obvious changes at the surface.
"Elevated seismicity continued for about 2 weeks after which the rate of shallow volcano-tectonic earthquakes decreased to levels considered background for Mount Martin. On January 27, AVO downgraded the Level of Concern to GREEN. Throughout this seismic swarm, no surface manifestations of the increase in seismicity were noted in satellite imagery or by passing pilots. The cause of this swarm remains uncertain (John Power, USGS, oral commun., 2007)."