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Landforms--Plate Tectonics. Forces that Build. Why is the earth’s surface so dynamic in contrast to the Moon?. Tectonic forces/Gradational forces. Abraham Ortelius-1564-’Theatre of the World’.
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Landforms--Plate Tectonics Forces that Build
Why is the earth’s surface so dynamicin contrast to the Moon?
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 carefully the coasts of the three [continents]."
What is so strange about coal being discovered in Antartica?How can it be explained?
Alfred Wegener-1911-German meteorologist/Theory of Continental Drift
The Earth's magnetic field is slowly changing and appears to have been changing throughout its existence. When the tectonic plates form along the oceanic ridges, the magnetic field that exists is imprinted on the rock as they cool. The slowly moving plates act as a kind of a recorder leaving information about the strength and direction of past magnetic fields. By sampling these rocks and using radiometric dating techniques it has been possible to reconstruct the history of the Earth's magnetic field for the last 160 million years or so. Older "paleomagnetic" data exists but the picture is less continuous. An interlocking body of evidence, from many locations and times, give paleomagnetists confidence that these data are revealing a correct picture of the Earth's plate motions. In addition, if one "plays this tape backwards" the continents, which ride on the tectonic plates, reassemble along their edges with near perfect fits. These "reassembled continents" have matching fossil floras and faunas.
There are 4 types of plate interactions. Each will have a different effect on landforms.1. Divergence2. Sideswipe (Transform boundary)3. Convergence4. Hot spots
“The quake hit San Francisco on Wednesday, April 18, at precisely 12 minutes past five o'clock in the morning. But San Francisco wasn't the only place to get hit… In San Jose, 8000 people were homeless. Santa Rosa, a town of 7000, was leveled. Trees were uprooted. Fences curved. And in some place the earth flowed like water. The quake had the impact of six million tons of TNT or roughly 12,000 times the power of the atomic bomb exploded over Hiroshima. It remains the greatest natural disaster suffered by a North American city.
I shouldn't wonder if San Francisco had sunk. That was some earthquake. We don't know but the Atlantic may be washing up at the feet of the Rocky Mountains!" ---Jack London
