25 June 1965
Vol 148, Issue 3678

About The Cover

Fault displacement associated with the 1964 Alaska earthquake. The northwest block (left) of the Hanning Bay Fault has been displaced upward between 4 and 5 meters, relative to the southeast block, along a high-angle reverse fault. The white coating on the reef rock of the upthrown block consists of the bleached remains of calcareous algae and bryozoans that lived below mean tide level. See page 1675. [George Plafker, U.S. Geological survey]