Grays
Lake, Idaho Earthquake Series, November 10, 1992
On November 10, 1992
an intense earthquake swarm began at Grays Lake, north of Soda
Springs, Idaho. The first two and largest events were composed
of multiples of three to four earthquakes. Within the multiples,
two of the earthquakes had magnitudes of ML 4.9 and 4.8 (BUT).
These events were
felt at Wayan, Georgetown, Bancroft, Montpelier, Idaho Falls,
and Pocatello, Idaho, and at Grover, Alpine, Freedom, Thayne,
Afton, Bedford, Etna, and Fairview, Wyoming.
This swarm had a total
of fifteen earthquakes exceeding ML 3.0. In a twenty-four hour
period, over 2000 earthquakes were observed on an analog record
for TMI. Some of the earthquakes had a component of low frequency
suggesting very shallow focal depths (possibly less than 5 km).
The temporary station
GLKI was installed late in the sequence to monitor the activity.
As result of this swarm, INEL installed two permenant stations
near Gray's Lake, ECRI and GRRI. The 2001 sequence is just south
of Gray's Lake near GRRI.
- personal communication,
Suzette Jackson, INEL, 2001.
