Transcript Scientists contribution to early Ideas of Plate Tectonics

Early Ideas of Plate Tectonics
Early Ideas of Crustal Movement:
 Early in this century, geologists thought that the ocean
basins and continents were fixed. During the past 70
years these ideas have brought about a scientific
revolution in which new evidence and data support a
slowly but continually moving planet.
 It was not until 1968 that a theory called Plate Tectonics
provided reliable evidence supporting a mobile Earth.
Reference:
Tarbuck and Lutgens
Pages 180 - 185
Early Ideas of Plate Tectonics
Important people of the past and the contribution they
made to support a moving Earth (Plate Tectonics).
1) F. B. Taylor
 In 1910, he published an article explaining the formation of the
Himalayan mountains by moving continents. His ideas were not
accepted because he failed to provide supporting evidence.
2) Alfred Wegener
 In 1915, Wegener rattled the scientific community again when
he published articles concerning continental drift. He suggested
a super continent called Pangaea existed approximately 200
million years ago and since gradually split apart. (evidence was
given, but no mechanism provided to support his ideas)
Early Ideas of Plate Tectonics
Important people of the past and the contribution
they made to support a moving Earth.
3) Arthur Holmes
 In 1950’s, he discovered the mechanism to explain why Earth’s
lithosphere can move, this was referred to as “convection
currents” in the mantle (asthenosphere).
4) Alexander DuToit
 In 1937, he mapped the fit of the continents more accurately by
using the continental Margins (shelves) instead of the coastlines.
See Africa and South America.
Early Ideas of Plate Tectonics
Important people of the past and the contribution
they made to support a moving Earth.
5) Harry Hess and Robert Deitz
 In the 1960’s, they suggested the “Sea Floor Spreading”
hypothesis and suggested that the sea-floor can be no greater
than 200 million years old.
6) Frederick Vine and Drummond Mathews
 In 1963, these two scientist studied the ocean floor and found
that the magnetism in the rocks appear to change (reverse) as
you move away from oceanic ridges. This idea was called
“magnetic reversals” and is known to support the idea of Sea
Floor Spreading (plate tectonics theory).
Early Ideas of Plate Tectonics
Important people of the past and the contribution
they made to support a moving Earth.
5) J. Tuzo Wilson
 In the 1965,
6) Xavier Le Pichon and Dan McKenzie
 In the 1970’s,
Early Ideas of Plate Tectonics
Important people of the past and the contribution
they made to support a moving Earth.
7) Tuzo Wilson
 Was a Canadian geologist who proposed the Plate Tectonic
Theory. He put forth the idea that, “Earth consisted of several
fragments called plates, instead of being made up of one rigid,
solid layer”. This revolutionized the way scientist think of
Earth today.