Reviewed by USGSCalifornia113y ago
M6.3 earthquake 237 km WSW of Ferndale, California
Thursday, May 6, 1915, 12:09:03 UTC · 40.148°N, 127.003°W
A magnitude 6.3 earthquake struck 237 km WSW of Ferndale, California on Thursday, May 6, 1915, 12:09:03 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M6.5 on August 5, 1910.
- Magnitude
- 6.3
- Strong · mw
- Depth
- 15 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquake
In context
How big was it, and why here?
Energy released
44 kilotons of TNT
That is about 3 times the Hiroshima bomb. It released about 92 times the energy of a magnitude 5.0.
Tectonic setting
31 km
from the nearest mapped plate boundary, between the Pacific and Juan de Fuca plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
15 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
Did You Feel It?
Where it was felt
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 100 km
USGS has not published any M2.5+ earthquake within 100 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 6 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 4 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1865
Fort Humboldt, Eureka
1 Oct 1865 · 232 km away · intensity IX
Moderate damage ($1–5M)
- 1871M5.9
Humboldt County
2 Mar 1871 · 239 km away · intensity VII
Limited damage (under $1M)
- 1898
N Coast,Mendocino County
14 Apr 1898 · 287 km away · intensity X
Limited damage (under $1M)
- 1855
Northern
20 Mar 1855 · 246 km away · intensity V
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.