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Alfred Wegner hypothesis' contenintal drifting
Around 1910 a German meteorologist began to come up with a hypothesis that the continents were once one landmass and had since drifted apart. He called this land mass Pangaea. He gathered evidence from everywhere he used fossils, land features, and the climates to back up his hypothesis. In the end though his hypothesis was rejected because he couldn't come up with the force that moved the continents. -
Arthur Holmes
He was the first man to try to date the Earth. In his first caculations he figured the Earth was about 1.6 billion years old. Then he revisited this number and came up with a new age which was 3 billion years old and he was able to do this by radioactive decay. In his first paper that 3 billion was the age he stuck with, but people thought the Earth was much younger like 20 to 100 million years old. Ever since his death we have estimated the Earth is about 4.5 billion years old. -
Kiyoo Wadati
He was a Japanese seismologist who mainly studied subduction zone earthquakes. After studing these areas he was able to put together a paper. Finally he got a seismic plate called the Wadati-Benioff Zone. -
U.S. Research Ship Atlantis
Atlantis is designed for research of the sea. First Atlantis was the start in a long line of Atlantises. the Atlantis can spend 60 days out in the ocean at a speed of 17,280 miles (nautical miles). It is 270 feet long and weighs 3,510 tons. There have been three Atlantises and only two have been retired so far. this ship will help us understand the world we live in even more. -
Hugo Benioff
Benioff invented the seismometer in 1932. He also charted deep earthquakes. A seismic place was named after him called the Wadati-Benioff zone. -
Alexander Du Toit
Alexander Du Toit madified Wegener's hypothesis. Alexander suggested that after Pangea split up there were two new major landmasses. He called these two land masses Lauraisaa, the landmass to the north, and Gondwenaland, the landmass to the south. -
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learning about the ocean floor
Scientist would map the ocean floor by using sonar equipment. By sending down sonar waves they would measure the time it took for the waves to get back and that determined the distance to the ocean floor. By using a magnetometer the scientist figured out the magnetic north and south poles at that time because the magnetic rock would point to them. Finally scientist found the rocks age from samples they brought up, in the Glomar challenger, these rocks had matching rocks on the opposite side. -
Henry Hess
In 1960 Henry Hess, an American geolegist proposed and idea to then scientific community. His idea was that Wegener was right about Continental drifting and the force that pushed the continents was the midocean ridges. He discribed them as a conveyor belt with the continents on them. The way it worked was that when new crust would form from the mid-ocean ridges it would push the old crust out of its way which would eventually push the continents. -
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Robert S. Dietz
This man added on to sea-floor spreading and infact named the process that. He elaborated on Hess' idea by saying that when the mid-ocean ridges bring up new material throwing the other part of the sea-floor out of its way, This slow makes the sea-floor sprea apart. -
Drummond Matthews and Fred Vine's finding
They were the men tht discovered that the Earth's crust isn't made up of just one big plate but many seperate plates. -
Sir Edward Bullard
He was the man that started to look at how all some shore lines like America adnEurope's match up like a puzzle. He also was able to match up radioactively-dated rocks on both South America And Africa -
The Glomar Challenger
The Glomar Challehger was a drilling ship. This ship was specialy built to drill samples out of the ocean floor. this helped scientist determne the age of the rock and throughout the whole process the figured out that the father away you get the older the rocks get. So this meant the youngest rocks were closer to the ridges.
