The June 12, 1988 earthquake
M5.3near East Foothills, California
A magnitude 5.3 earthquake 5.6 miles deep, centred in Santa Clara County. The 269th strongest in California’s record since 1900, and the strongest within 50 miles since a magnitude 5.7 on March 31, 1986. 9 aftershocks of magnitude 2.5 or more followed within 30 days.
The earthquake
- Magnitude
- 5.3
- local magnitude (ml)
- Depth
- 5.6 mi
- 9.1 km below the surface
- Local time
- Sunday, June 12, 1988
- 18:45 PDT; 01:45 UTC on Jun 13, 1988
- In California’s record
- 269th
- strongest of 97,065 since 1900
USGS ANSS Comprehensive Earthquake Catalog, event nc10087352 (“6 km E of East Foothills, California”). 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.
9
Aftershocks in 30 days
3.3
Largest aftershock, Jun 13, 1988
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
- Santa Clara CountyCA · inside
- Alameda CountyCA · 9.3 mi
- San Joaquin CountyCA · 14.5 mi
- Stanislaus CountyCA · 14.9 mi
- San Mateo CountyCA · 21.1 mi
- Santa Cruz CountyCA · 21.2 mi
- Contra Costa CountyCA · 25.5 mi
- San Benito CountyCA · 31.5 mi
- Monterey CountyCA · 32.8 mi
- Merced CountyCA · 33.4 mi
- San Francisco CountyCA · 40.8 mi
- Sacramento CountyCA · 43.3 mi
- Solano CountyCA · 45.9 mi
- Marin CountyCA · 48.8 mi
Earthquakes around the epicentre
2,055 earthquakes of magnitude 3 or more within 50 miles of this epicentre since 1973.
Earlier earthquakes of magnitude 5 or more within 50 miles, strongest first
- July 1, 1911M6.5
- October 22, 1926M6.3
- October 22, 1926M6.3
- August 2, 1903M6.2
- April 24, 1984M6.2
- June 11, 1903M6.1
- September 4, 1955M5.8
- March 10, 1910M5.8
- August 6, 1979M5.8
- January 24, 1980M5.8
USGS ANSS Comprehensive Earthquake Catalog. Local time is the time zone of the county nearest the epicentre. Magnitudes are as the catalogue reports them.