The July 27, 1902 earthquake
M5.8Near Los Alamos, California
A magnitude 5.8 earthquake, centred in Santa Barbara County. The 108th strongest in California’s record since 1900, and the strongest within 50 miles in the catalogue, which runs from 1900. 1 aftershock of magnitude 2.5 or more followed within 30 days.
The earthquake
- Magnitude
- 5.8
- local magnitude (ml)
- Depth
- —
- Not recorded
- Local time
- Sunday, July 27, 1902
- 22:57 PST; 06:57 UTC on Jul 28, 1902
- In California’s record
- 108th
- strongest of 97,065 since 1900
USGS ANSS Comprehensive Earthquake Catalog, event ushis404 (“Near Los Alamos, 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.
1
Aftershocks in 30 days
5.8
Largest aftershock, Jul 31, 1902 · its page
0
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.
- Before the modern seismic networks of the 1970s many small aftershocks went unrecorded, so early sequences read short.
Counties and cities within 50 miles
Distance from the epicentre to each county boundary (zero when inside) and to each city centre.
Counties
- Santa Barbara CountyCA · inside
- San Luis Obispo CountyCA · 9.2 mi
- Kern CountyCA · 46.3 mi
Cities, largest first
- Santa MariaCA · 9.5 mi
- Santa BarbaraCA · 47.7 mi
- San Luis ObispoCA · 35.6 mi
- LompocCA · 10.3 mi
- GoletaCA · 39.8 mi
- Arroyo GrandeCA · 24.7 mi
- Grover BeachCA · 25.4 mi
- Morro BayCA · 47.3 mi
Earthquakes around the epicentre
169 earthquakes of magnitude 3 or more within 50 miles of this epicentre since 1973.
No earlier earthquake of magnitude 5 or more within 50 miles in the catalogue since 1900.
USGS ANSS Comprehensive Earthquake Catalog. Local time is the time zone of the county nearest the epicentre. Magnitudes are as the catalogue reports them.