Snowball Earth Theory

Halie M.

What is Snowball Earth?

700 million years ago the earth became covered in a heavy duty thick sheet of ice. Since it was such thick sheet of ice there was no way the sun could get to the center to melt it. Also due to how cold it was on Earth at the time they said it was almost as if it was

Mars. In the result of Glacial Flowage (glacial erratics, tills, moraines, eskers) gave us proof. This crazy thing of Earths past lasted for nearly 200million years!!

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What caused Snowball Earth

When the atmosphere of Earth lowered, it made greenhouse gases increase. This caused ice to form quickly and became very thick very fast. So when then the suns heat rays tried to melt the ice, a thing called feed-back happened which is when sun is not let through due to the ice reflecting the ice rays. If earth ended up to be covered half in ice again it would not stop spreading due to feedback. If this were to happen again it probably would last 200 million years or longer.
Snowball Earth?

How it Ended

The Snowball Earth ended by the Co2 radioactive build-up over a long period of time which slowed down he cold increase. Which then caused volcanic and metamorphic Co2 to be made. Also the movement of plate tectonics and gravity caused heat to form. And due to chemical mixes, explosions and heat underground forming.
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Evidence that Snowball Earth happened

Scientist can tell that Snowball Earth happened because it has been seen in the levels of the Earth, rocks that have been dug up and also deposits. Another way they could tell was because of past ocean temperatures and the way that it changed over time. Also the temperature of the water. And because of geomatic field.

Sources

"Beyond Earthly Skies." : Snowball Earth: Thawing a Snowball. N.p., n.d. Web. 07 Nov. 2014. <http://beyondearthlyskies.blogspot.com/2013/09/snowball-earth-thawing-snowball.html>.

"Slushball Earth May Have Helped Trigger Life's Explosion." New Scientist 196.2633 (2007): 18. Science Reference Center. Web. 3 Nov. 2014.

Snowball Earth (BBC Documentary). 2013. Web. <http://unofficialnetworks.com/2013/08/snowball-earth-bbc-documentary>.

"SNOWBALL EARTH." SNOWBALL EARTH. U.S. National Science Foundation (EAR - Geology & Paleontology Division), 2009. Web. 04 Nov. 2014.

"Snowball Earth?" YouTube. YouTube, n.d. Web. 07 Nov. 2014. <https://www.youtube.com/watch?v=mX3pHD7NH58>.