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along oceanic trenches and submarine mountain
ranges. OCE 661 Ocean floor mapping
About two thirds of the Earth's surface lies
beneath the oceans.
• Before the 19th century, the depths of the
open ocean were largely a matter of
speculation, and most people thought that the
ocean floor was relatively flat and featureless.
• 19th century: deep-sea line soundings
(bathymetric surveys) in the Atlantic and
• 1855, a bathymetric chart published by U.S.
Navy Lieutenant Matthew Maury revealed the
first evidence of underwater mountains in the
central Atlantic (which he called "Middle
Ground"). OCE 661 • later confirmed by survey ships laying the trans-Atlantic
• after World War I (1914-18): echo-sounding devices
began to measure ocean depth by recording the time it
took for a sound signal from the ship to bounce off the
ocean floor and return. –> ocean floor is much more
rugged than previously thought.
–> demonstrated the continuity and roughness of the
submarine mountain chain in the central Atlanti...
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- Winter '14
- Plate Tectonics, Atlantic Ocean, Mantle, Alfred Wegener, Richards