Smithsonian Report, 1961— Benson 



PLATE 4 



Enlarged view of cut and polished section of a 1-inch core of glassy basalt recovered from 

 near the top of the second layer of the oceanic crust, about 575 feet below the ocean floor 

 under 11,700 feet of water, off Guadalupe Island, April 1961. (Photograph by U.S. 

 Geological Survey.) 



