Historic Earthquakes
Prince William Sound, Alaska
1964 March 28 03:36 UTC
1964 March 27 05:36 p.m. local time
Magnitude 9.2
Largest Earthquake in Alaska
Damage Photos
One span of the "Million Dollar" truss-bridge of the former
Copper River and Northwestern Railroad was dropped into the
Copper River by the earthquake, and the other truss spans
were shifted on their piers.
The earthquake shifted the steel trusses of the Copper
River and Northwestern Railroad bridge near Round Island
from 1 to 2 feet. This view shows one of the displaced
trusses, which pounded against an adjacent steel girder
span. The girder span was moved to the right, its
concrete pedestal was rotated, and the girder span almost
fell into the river. Note the shortening indicated by
buckling of the guardrail.
A series of earthquake triggered landslides in glacial
deposits disrupted almost a mile of The Alaska Railroad
main line at Potter Hill, near Anchorage.
Close-up of damaged homes at Turnagain Heights landslide,
Anchorage.
A subsidence trough (or graben) formed at the head of the
"L" Street landslide in Anchorage during the earthquake.
The slide block, which is virtually unbroken ground to the
left of the graben, moved to the left. The subsidence
trough sank 7 to 10 feet in response to 11 feet of
horizontal movement of the slide block. The volume of the
trough is theoretically equal to the volume of the void
created at the head of the slide by movement of the slide
block. A number of houses seen in this photograph were
undercut or tilted by subsidence of the graben. Note also
the collapsed Four Seasons apartment building
and the undamaged three story
reinforced concrete frame building beside it, which are on
the stable block beyond the graben.
A detail illustrating the violence of the surge waves that
struck Whittier: man holds mounted tire where wave has
driven a piece of wood through the tire.
Trees up to 24 inches in diameter and between 88 and 101 feet above
sea level were broken and splintered by the surge wave generated
by an underwater landslide in Port Valdez, Prince William Sound.
The rails in this approach to a railroad bridge near the
head of Turnagain Arm were torn from their ties and
buckled laterally by channelward movement of the river
banks during the earthquake. The bridge was also
compressed and developed a hump from vertical buckling.
The rails were buckled by lateral movement of the embankment fill
toward an underlying culvert, which had collapsed.
Photos from the Earth Science Photographs from the U.S. Geological Survey Library, by Joseph K. McGregor and Carl Abston, U.S. Geological Survey Digital Data Series DDS-21, 1995.

