PRINCE WILLIAM SOUND EARTHQUAKE, MARCH 28, 1964

Turnagain Heights Landslide, Anchorage, Alaska

[LANDSLIDES] This slide shows the Turnagain Heights landslide in Anchorage. Seventy-five homes twisted, slumped, or collapsed when liquefaction of subsoils caused parts of the suburban bluff to move as much as 2,000 feet (606 m) downward toward the bay forming a complex system of ridges and depressions. The slide developed because of a loss in strength of the soils, particularly of lenses of sand, that underlay the slide. The motion involved the subsidence of large blocks of soil, the lateral displacement of clay in a 25 feet (7.6 m) thick zone, and the simultaneous lateral translation of the slide debris on liquefied sands and silts. Photograph Credit: NOAA/NGDC.