Disclaimer: St. Helens Earthquakes
There have been at least 4,000 microearthquakes recorded at Mt. St. Helens
since September 23, 2004. The small fraction that you're seeing represents
the largest, most easily located earthquakes only.
How this Affects our Webpages
Earthquake Counts: Our plots of earthquake counts are far too small.
Earthquake Locations: There are far more earthquakes at St. Helens than the earthquake location and time-depth figures suggest. However, the range of earthquake locations and depths, as shown in the figures, should be accurate.
Earthquake Magnitudes: The magnitude-time plot really only characterizes maximum magnitude.
Energy Released: Our energy release calculations are too low. Changes in energy release may
be accurately represented.
By our estimates, only 2-4% of earthquakes since September 25, 2004 are processed and located.
The catalog is relatively complete through September 24, 2004.
This is file SEIS/PNSN/HELENS/msh_disclaimer.html, last modified
12/07/06 (14:31)
. If you see any problems e-mail:
seis_web@ess.washington.edu
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