Event Name : Augustine 1998/7
|Start:||July 1998 ||Observed|
|Lahar, debris-flow, or mudflow: ||
|Eruption Type:||Not an eruption.|
McGimsey and others (2003) consider the 1998 activity non-eruptive : "On July 12, 1998, charter pilots from Homer who routinely fly by Augustine noted fingers of mud up to about 250 ft wide (76 m) extending down from the cloud-enshrouded summit to snowfields on the upper north-northeastern flank. Other snowfields near the summit were discolored by fine gray ash deposits. One particular flow of pinkish muddy material had reached the sea. AVO received this information on July 13 and immediately canvassed the seismic, tiltmeter, and temperature sensor data for the previous several days. Rockfall and small avalanches are a common, if not everyday, occurrence on Augustine and have recognizable seismic signatures. The seismic records for July 10 showed a larger than usual avalanche event at 21:23 ADT that lasted at least 30 seconds. On July 14, the same charter pilots flew by Augustine - this time during clear weather - they reported that a portion of the spine that was extruded from the summit dome in 1986 (see figure 5 in original text) had collapsed and was the apparent source of the small mudflows observed several days earlier. They also reported that the volcano seemed to be steaming more than usual. AVO geophysicist John Power measured fumarole temperatures near the base of the toppled spine later in July and reported temperatures of 93.8 and 96.9oC, similar to those measured in 1997."