April 2011 Fukushima earthquake
| UTC time | 2011-04-11 08:16:12 |
|---|---|
| ISC event | 16416735 |
| USGS-ANSS | ComCat |
| Local date | 11 April 2011 |
| Local time | 17:16 JST |
| Magnitude | 6.6 Mw |
| Depth | 13 km (8 mi) |
| Epicenter | 37°00′04″N 140°24′04″E / 37.001°N 140.401°E |
| Fault | Iodzawa fault, Yunodake fault |
| Type | Normal |
| Areas affected | Japan |
| Max. intensity | MMI VIII (Severe) JMA 6− |
| Peak acceleration | 2.11 g 2071.7 Gal |
| Tsunami | No |
| Landslides | Yes |
| Casualties | 4 dead, 10 injured |
A strong intraplate earthquake, with a magnitude of 6.6 on the moment magnitude scale (Mw ), occurred at 17:16 JST (08:16 UTC) on 11 April, in the Hamadōri region of Fukushima, Japan. It had a shallow focus of 13 km (8.1 mi), with an inland epicentre, about 36 km (22 mi) west of Iwaki, causing widespread strong to locally severe shaking. It was triggered by the 2011 Tōhoku earthquake, and the strongest such event to have its epicentre located inland.
The earthquake occurred as a result of normal faulting to the west of Iwaki, and triggered numerous landslides across adjacent mountainous areas. A few fires broke out, and 220,000 households lost electricity. Officials issued localised tsunami alerts, though no significant waves were generated. The earthquake caused little structural damage, but killed four people and injured ten others. The strong ground movements caused by the reactivation of two geological faults in this area of low seismicity, prompted researchers to conduct extensive surveys in the region.