  | |
| Local date | 22 December 856 |
|---|---|
| Local time | At night |
| Magnitude | 7.9 Ms |
| Epicenter | 36°12′N 54°18′E / 36.2°N 54.3°E[1] |
| Fault | Astaneh Fault System |
| Type | Strike-slip |
| Areas affected | Iran |
| Max. intensity | MMI X (Extreme) |
| Casualties | 200,000 dead |
The 856 Damghan earthquake or the 856 Qumis earthquake occurred on 22 December 856 (242 AH). The earthquake had an estimated magnitude of 7.9, and a maximum intensity of X (Extreme) on the Mercalli intensity scale. The meizoseismal area (area of maximum damage) extended for about 350 kilometres (220 mi) along the southern edge of the eastern Alborz mountains of present-day Iran including parts of Tabaristan and Gorgan. The earthquake's epicenter is estimated to be close to the city of Damghan, which was then the capital of the Persian province of Qumis. It caused approximately 200,000 deaths and is listed by the USGS as the sixth deadliest earthquake in recorded history.[2] This death toll has been debated.[3]
- ^ National Geophysical Data Center / World Data Service (NGDC/WDS): NCEI/WDS Global Significant Earthquake Database. NOAA National Centers for Environmental Information (1972). "Comments for the Significant Earthquake". NOAA National Centers for Environmental Information. doi:10.7289/V5TD9V7K. Retrieved 17 December 2021.
- ^ USGS (14 April 2011). "Earthquakes with 50,000 or More Deaths". Archived from the original on 5 June 2013. Retrieved 18 October 2011.
- ^ Sorkhabi, Rasoul (21 December 2017). Tectonic Evolution, Collision, and Seismicity of Southwest Asia: In Honor of Manuel Berberian's Forty-Five Years of Research Contributions. Geological Society of America. p. 146. ISBN 978-0-8137-2525-3.