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Apr 14, 1527
Abraham Orteilus
Ortelius was the first to underline the geometrical coincidence between the coasts of America and Europe-Africa, and to propose continental drift as an explanation. Kious described Ortelius' thoughts in this way:[5]
Abraham Ortelius in his work Thesaurus Geographicus ... suggested that the Americas were "torn away from Europe and Africa ... by earthquakes and floods" and went on to say: "The vestiges of the rupture reveal themselves, if someone brings forward a map of the world and considers car -
Nicolaus Steno Law of Superposition
Steno challenged the century-old belief that the Earth had remained unchanged since its creation. Steno took the dynamic view, based on his observations of layers in the Earth's crust. These different strata, he believed, had been left by former seas, which were altered by erosion, earthquakes, and volcanic eruptions. -
Period: to
Plate Tectonics
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James Hutton Uniformitarian Principle
The forces that work now have always happened. The present is the key to the past. -
Alfred Lothar Wegener is born
Theory: (1912) Continental Drift (hypothesized that continents were slowly drifting around Earth) thought that there was a landmass called Pangea (where all land was connected)
Evidence: There were similarities of the fossils and rocks from one side of the Atlantic to the other side. Also, it looked like continents all fit together. His hypothesis was not accepted until the 1950s -
Arthur Holmes is born
Holmes major contribution was the hypothesis that the radioactive decay occurring in the mantle of Earth would generate heat, and thereby convection currents that would be the means by which the continents could move. It was his passion and commitment to radiometric dating that allowed him to develop this hypothesis. -
Dan Mckenzie is born
Provided a mathematical model explaining them movement of the earths crust. -
Henry Hess Sea Floor Spreading Theory
He theorized that the ocean floor is most only a few hundred million years old. This is how long it takes for molten rock to rise up and ooze out of the volcano. The ocean would open up and hot magma would come out and cool and expand.
