Reviewed by USGSIran119y ago
M7.3 earthquake 43 km NW of Delījān, Iran
Saturday, January 23, 1909, 02:48:29 UTC · 34.306°N, 50.396°E
A magnitude 7.3 earthquake struck 43 km NW of Delījān, Iran on Saturday, January 23, 1909, 02:48:29 UTC, at a depth of 15.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.
- Magnitude
- 7.3
- Major · mw
- Depth
- 15 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VIII
- Severe (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
1.3 megatons of TNT
That is about 89 times the Hiroshima bomb. It released about 2,818 times the energy of a magnitude 5.0.
Tectonic setting
288 km
from the nearest mapped plate boundary, between the Arabian and Eurasian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
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 200 km
USGS has not published any M2.5+ earthquake within 200 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists no earlier M5.0+ earthquakes within 300 km.
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 14 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 77,500 recorded deaths. The most severe:
- 1755
N: Tabriz,Kashan
7 Jun 1755 · 107 km away
40,000 deathsSevere damage ($5–24M)
- 1778
Kashan
30 Jan 1778 · 115 km away
30,000 deathsSevere damage ($5–24M)
- 1909M7.3
Silakor
23 Jan 1909 · 0 km away · intensity IX
5,500 deathsModerate damage ($1–5M)
- 1844M6.4
Kashan, Qamsar, Kamu, Kushian, Chuka
12 May 1844 · 121 km away
1,500 deathsSevere damage ($5–24M)
- 1830
Damavand,Tehran,Semnan,Damghan
9 May 1830 · 219 km away
500 deathsSevere damage ($5–24M)
- 1825M6.7
Harhaz
1825 · 283 km away · intensity VIII
Severe damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.