Earthquake activity beneath Mount St. Helens remained at a low level during January 1996. Fourteen small earthquakes occurred beneath the volcano during January, compared to 26 earthquakes in December 1995. This continues a trend of declining activity since October 1995. There were no explosions or other unusual events at the volcano during January.
Caption: Cross-sectional view showing the locations of earthquakes beneath Mount St. Helens during January 1996. The cross-section represents a vertical slice of the crust downward from line A-A' in the map view. The earthquakes occurred in and around the magma conduit system that leads from the magma reservoir to the dome. In this graph, 0 depth is referenced to 1.5 km (about 1 mile) below the current summit of Mount St. Helens (8,363 feet above sea level). Data and graph provided by the Geophysics Program, University of Washington.
Caption: Graph showing relationship between time and depth of earthquakes beneath Mount St. Helens from February 1, 1995 to January 31, 1996. In this graph, 0 depth is referenced to 1.5 km (about 1 mile) below the current summit of Mount St. Helens (8,363 feet above sea level). Data and graph provided by the Geophysics Program, University of Washington.
The U.S. Geological Survey and University of Washington monitor earthquakes and other activity at Mount St. Helens as part of the USGS Volcano Hazards Program. Information updates will be posted here during the first week of each month, or more often if conditions warrant.
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