Description: From Neal and others (2014): "Low level seismicity was recorded at Makushin Volcano throughout 2010. At about 7:00 p.m. Alaska Standard Time on February 17, a veteran pilot noted an unusual dark plume over the volcano during exceptionally clear conditions. Later, Guardian Flight paramedic Wayne Boots sent AVO images of strong fumarolic output at the Makushin summit from February 19. AVO reviewed seismic data and saw no change of any significance related to a possible plume. On February 24, a strong vapor plume was visible with satellite imagery but again, no change in seismicity was noted. On March 3, AVO satellite analysts reported slightly elevated temperatures in the vicinity of the summit craters; not an unusual observation for the fumarolically active summit of Makushin.
Seismicity increased slightly with a small swarm on April 7 and again in May. AVO did not elevate the Aviation Color Code or Alert Level for Makushin for either of these slight departures from background."