The April 20, 2002 earthquake
M5.3near Au Sable Forks, New York
A magnitude 5.3 earthquake 3.0 miles deep, centred in Clinton County. The 2nd strongest in New York’s record since 1900, and the strongest within 50 miles in the catalogue, which runs from 1900. 2 aftershocks of magnitude 2.5 or more followed within 30 days.
The earthquake
- Magnitude
- 5.3
- as reported (mlg)
- Depth
- 3.0 mi
- 4.8 km below the surface
- Local time
- Saturday, April 20, 2002
- 06:50 EDT; 10:50 UTC
- In New York’s record
- 2nd
- strongest of 187 since 1900
USGS ANSS Comprehensive Earthquake Catalog, event ld2002042000 (“8 km NNW of Au Sable Forks, New York”). 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.
2
Aftershocks in 30 days
3.7
Largest aftershock, Apr 20, 2002
2
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
- Clinton CountyNY · inside
- Essex CountyNY · 5.1 mi
- Franklin CountyNY · 11.9 mi
- Grand Isle CountyVT · 16.8 mi
- Chittenden CountyVT · 16.9 mi
- Addison CountyVT · 25.6 mi
- Franklin CountyVT · 27.2 mi
- Lamoille CountyVT · 39.1 mi
- Hamilton CountyNY · 39.6 mi
- Washington CountyVT · 42.5 mi
- St. Lawrence CountyNY · 47.3 mi
Cities, largest first
- BurlingtonVT · 22.6 mi
- South BurlingtonVT · 26.0 mi
- PlattsburghNY · 17.1 mi
- Essex JunctionVT · 28.8 mi
Earthquakes around the epicentre
23 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.