1983 Borah Peak earthquake
| UTC time | 1983-10-28 14:06:09 |
|---|---|
| ISC event | 567352 |
| USGS-ANSS | ComCat |
| Local date | October 28, 1983 |
| Local time | 08:06 MDT |
| Magnitude | 6.9 Mw |
| Depth | 16 km (9.9 mi) |
| Epicenter | 44°05′N 113°48′W / 44.08°N 113.8°W |
| Fault | Lost River Fault |
| Type | Normal |
| Areas affected | Central Idaho United States |
| Total damage | $12.5 million |
| Max. intensity | MMI IX (Violent) |
| Landslides | Yes |
| Aftershocks | 5.6 Mw Oct 28 at 19:51 UTC 5.5 Mw Oct 29 at 23:29 UTC |
| Casualties | 2 killed, three injured |
The 1983 Borah Peak earthquake occurred on October 28, at 8:06:09 a.m. MDT in the western United States, in the Lost River Range at Borah Peak in central Idaho.
The shock measured 6.9 on the moment magnitude scale and had a maximum Mercalli intensity of IX (Violent). It was the most violent earthquake in the lower 48 states in over 24 years, since the 1959 Hebgen Lake earthquake in nearby southwestern Montana.