1139 Ganja earthquake
| Local date | 30 September 1139 |
|---|---|
| Magnitude | 7.7 MLH, 7.5 Ms, 7.0–7.3 Mw |
| Depth | 23–16 km (14.3–9.9 mi) |
| Epicenter | 40°18′N 46°12′E / 40.3°N 46.2°E |
| Areas affected | Seljuk Empire (present-day Azerbaijan) |
| Max. intensity | MMI IX (Violent) or MMI XI (Extreme) |
| Casualties | 230,000–300,000 dead (estimation) |
The 1139 Ganja earthquake was one of the worst seismic events in history. It affected the Seljuk Empire and the Kingdom of Georgia, in modern-day Azerbaijan and Georgia. The earthquake had an estimated magnitude of 7.7 MLH, 7.5 Ms and 7.0–7.3 Mw. A disputed death toll of 230,000–300,000 resulted from this event, making it one of the deadliest earthquakes ever recorded.