Hess Harry Hammond

Hess

(hĕs), Harry Hammond 1906-1969.
American geologist who studied the sea floor and developed the theory of sea-floor spreading. He theorized that sea floors were constantly renewed by the flow of magma from the Earth's mantle through the oceanic rifts. Hess's hypothesis became an important component of the theory of plate tectonics.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.