M A S T E R P A G E
Continental Drift: 1910 to 1960
The theory of continental drift originated early in this century, but it did not gain general acceptance until the late
1960s. Between 1910 and 1912, the German meteorologist, geophysicist, and explorer Alfred L. Wegener
formulated the theory called continental drift. He collected evidence from the rocks, fossils, and climatic records
of several continents to show that they had once been joined together. Wegener knew little about the oceanic
crust, which had not yet been explored, and thought that the continents merely moved horizontally, plowing
through the oceanic crust.
Plate Tectonics: 1960 to the Present
In the early 1960s, British geophysicists Fred Vine and Drummond Matthews used magnetic data to show that the
ocean floor is spreading apart at the mid-ocean ridges. As they shared the evidence for the process they called
sea-floor spreading, scientists began to realize that the continents were also moving. By 1968, a new explanation
for the dynamics of Earth’s surface had been created, combining Wegener’s hypothesis with evidence from the
ocean floor. Scientists call it the theory of plate tectonics.
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