The February 21, 2008 earthquake
M5.9near Wells, Nevada
A magnitude 5.9 earthquake 4.9 miles deep, centred in Elko County. The 16th strongest in Nevada’s record since 1900, and the strongest within 50 miles in the catalogue, which runs from 1900. 278 aftershocks of magnitude 2.5 or more followed within 30 days.
Watch the sequence unfoldMagnitude 5.9 · February 21, 2008
How the ground moved
Every recorded earthquake in the sequence, in order, through the month after.
The earthquake
- Magnitude
- 5.9
- moment magnitude (mw)
- Depth
- 4.9 mi
- 7.9 km below the surface
- Local time
- Thursday, February 21, 2008
- 06:16 PST; 14:16 UTC
- In Nevada’s record
- 16th
- strongest of 8,110 since 1900
USGS ANSS Comprehensive Earthquake Catalog, event nn00234425 (“8 km ENE of Wells, Nevada”). The USGS event page carries the ShakeMap, felt reports and the official summary.
Aftershocks
Earthquakes of magnitude 2.5 or more within 20 miles of the epicentre in the 30 days after.
278
Aftershocks in 30 days
5.1
Largest aftershock, Feb 21, 2008 · its page
107
On the first day
0
In the 7 days before
- The search radius is the surface rupture length expected for an earthquake of this magnitude (Wells and Coppersmith, 1994), at least 20 and at most 600 miles, so a great earthquake's sequence is counted along its whole fault.
Counties and cities within 50 miles
Distance from the epicentre to each county boundary (zero when inside) and to each city centre.
Counties
- Elko CountyNV · inside
- Box Elder CountyUT · 44.4 mi
- Tooele CountyUT · 44.4 mi
Earthquakes around the epicentre
159 earthquakes of magnitude 3 or more within 50 miles of this epicentre since 1973.
USGS ANSS Comprehensive Earthquake Catalog. Local time is the time zone of the county nearest the epicentre. Magnitudes are as the catalogue reports them.