What happens when you have a planet with a broken crust, a slow-flowing mantle and a hot, liquid outer core?
KTS budding geologists set off to investigate.
Our planet is for the most part solid and firm but the tectonic plates--those floating portions of mantle and crust-- are shifting, and they have been doing that for a few million years! That movement created the continents and oceans we are familiar with today.
But how do we know the Earth's plates are moving? Ask Alfred Wegener, a meteorologist who in the early 1900's came up with a big idea: a long time ago, he said, there was one enormous supercontinent that later broke up into separate plates that drifted from each other over time. How did he come up with this idea? He noticed, as you probably did too, that the different continents fit together like giant puzzle pieces. he also saw the rock layers and certain ancient fossils were very similar in continents now thousands of miles apart.
Because he couldn't explain what caused the plates to move, his theory was not readily accepted. Much debate ensued among those supporting "continental drift" and those who believed the continents were fixed--the fixists.
This clever video tells us the story:
Today, KTS geologists joined the debate and using puzzle pieces of the Earth's continents and fossil evidence, they investigated Wegener's theory.
They also looked into what happens when the plates move and, say, crash into each other! They did it with Graham crackers!
A delicious class!
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