Denali Earthquake Oct. 23, 2002
This is a high-altitude view eastward along the main strand of the
Denali fault, which is marked here by a prominent linear valley
along the southern edge of the Alaska Range. The view shows the
approximate location of the epicenter of the magnitude 6.7 earthquake
that occurred in the early morning of October 23, 2002. The Denali
fault is a major fault that follows an arcuate trace across southern
Alaska, following the Alaska Range for much of its length. The eastern
part of the fault shows about 400 km of right-lateral strike-slip
displacement since early Tertiary time. Offset surficial deposits
and seismicity indicate that the fault has remained active to the
present, but the October 23 earthquake is the largest seismic event
so far recorded on the fault. The Nenana River, in the foreground,
marks the eastern boundary of Denali National Park, and the Parks
Highway, which connects Anchorage and Fairbanks lies immediately
east of the river. The epicenter was approximately 25 miles (40
km) east of the highway. In the distance, the rugged peaks of Mts.
Deborah and Hess rise to about 12,000 feet (3650 m) just north of
the bend in the Denali fault.
(Photo and interpretation by Wesley K. Wallace, Geophysical Institute,
University of Alaska Fairbanks)
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