FIGURE 8.21 Turnagain Heights slide caused by the 1964 Alaskan earthquake. A Vibrations from the earthquake caused cracks to appear near the edge of the bluff. B. Within seconds blocks of land began to slide toward the sea on a weak layer of day. In less than 5 minutes, as much as 200 meters of the Turnagain Heights bluff area had been destroyed. C. Photo of a small portion of the Tumagain Heights slide. (Photo courtesy of US Geological Survey)