Reviewed by USGSIraq110y ago
M5.5 earthquake 39 km SSW of Ḩalabja, Iraq
Tuesday, July 24, 1917, 16:13:17 UTC · 34.869°N, 45.779°E
A magnitude 5.5 earthquake struck 39 km SSW of Ḩalabja, Iraq on Tuesday, July 24, 1917, 16:13:17 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
- 5.5
- Moderate · 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
2 kilotons of TNT
That is about 1/7 of the Hiroshima bomb. It released about 5 times the energy of a magnitude 5.0.
Tectonic setting
77 km
from the nearest mapped plate boundary, between the Arabian and Eurasian 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 75 km
USGS has not published any M2.5+ earthquake within 75 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1 M5.0+ earthquake 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 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 180 recorded deaths. The most severe:
- 1864M6.4
Zurbatiyah, Badrah, Tursaq, Baghdad
2 Dec 1864 · 167 km away · intensity VIII
100 deathsModerate damage ($1–5M)
- 1781
Al-Mawsil (Mosul)
1781 · 290 km away · intensity X
80 deathsModerate damage ($1–5M)
- 1769
Baghdad
1 May 1769 · 239 km away · intensity VII
Severe damage ($5–24M)
- 1857
Lake Urmia (Lake Urmi)
9 Apr 1857 · 285 km away
Severe damage ($5–24M)
- 1872
Hamadan
Jun 1872 · 207 km away
Severe damage ($5–24M)
- 1872
Songhor(Sonqor)
16 Sep 1872 · 166 km away
Severe damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.