Small Glacial Outburst Flood from Spurr in Alaska

The plume from the August 18, 1992 eruption of Alaska's Spurr. The eruptive period started on June 27, 1992. Image by R.G. McGimsey, courtesy of AVO/USGS. Brief note, just because I love coincidences like this: Twenty years ago today (June 27), Mt. Spurr in Alaska produced one of the largest eruptions of the Aleutians in the past 50 years - a VEI 4 eruption that featured at 20 km / 65,000 foot plume. That eruption deposited 2 mm of ash as far at 270 km from the volcano. Over the next few months following the June 27 eruption, a number of smaller eruptions followed before the volcano went quiet again in September 1992. You can check out a nice "guided tour" of images from the 1992 volcanic crisis at Spurr. Why do I bring this up? Well, Spurr must have felt festive as the volcano had a "minor increase in seismicity" that coincided with a small glacial outburst flood on Monday (June 25). The increase in earthquake activity was brief - by the morning of the 26th, the seismicity was over. Now, this doesn't mean the volcano is ramping up for anything. Spurr is snow/ice-covered, so slow melting under the ice could pool water until it is dramatically released with an ice or sediment dam holding it back releases. The Alaska Volcano Observatory mentions that Spurr had a similar event in June 1993 as well. However, it is a good way to remind us that Alaskan volcanoes are always a threat to produce significant eruptions. Be sure to check out AVO's Spurr page to see the webcam and webicorders for the volcano.