2002 M7.9 Denali Fault Earthquake

 

 

The fault rupture for the Denali Fault Earthquake was a complex rupture, occurring on three separate faults. Rupture started on the previously unrecognized Susitna Glacier Thrust fault, a splay fault south of the McKinley strand of the Denali fault system (DFS). The rupture then transferred onto the main strand of the DFS and continued eastward as a right-lateral strike-slip event for ~137 miles (220 km) until it reached the Totschunda fault. At that point, it right-stepped onto the more south-easterly trending Totschunda fault rupturing an additional ~44 miles (70 km).

A team of geologists surveyed the total length of the ruptured faults and reported 4 meters of maximum vertical offsets on the Susitna Glacier Thrust Fault and maximum horizontal offsets of 8.8 meters west of the Denali and Totschunda fault junction.

fault line

Photo and interpretation by Wesley K. Wallace, Geophysical Institute, University of Alaska Fairbanks