Magnitude 7.9 Earthquake Strikes South-Central Alaska

Magnitude 7.9 Earthquake Strikes South-Central Alaska

An intense earthquake struck central Alaska about 90 miles south of Fairbanks at 1:12 p.m. local time on November 3, 2002. With a magnitude of 7.9, the quake was the ninth largest to be recorded in the United States. The shaded-relief image above shows the location of the earthquake, which occurred on the Denali fault alongside the Alaska Range. The fault appears as a dark arch running across the image.

The powerful quake knocked sections of the trans-Alaska oil pipeline off its supports, cracked nearby roads, triggered smaller earthquakes in California and Montana, and even rocked houseboats in Louisiana lakes. A six mile stretch of the main highway running between Anchorage and Fairbanks had to be closed after a three-foot-wide fissure opened up in the road. At some places along the fault, the quake caused the ground on one side of the fault to slide horizontally a full 2.5 meters (8.2 feet) past the other side. Only one relatively minor injury was reported when a 76-year-old woman broke her arm after losing her balance on the stairs of her home.

For more information, visit the USGS National Earthquake Information Center Earthquake Bulletin.

Image courtesy USGS Alaska Science Center