earth's shifting tectonic plates

 

Here.

very difficult to stop

Stones rolling downhill.

How we know the earth is older than 6000 years

All our evidence for changes in the Earth comes from looking at rocks. Folds and fossils in sedimentary rocks, radioactive dating and the weathering of ancient craters show that the oldest rocks are about 4000 million years old. That means the Earth must be at least as old as this. It is from being able to understand the age of the rocks on the earth that we know how old the earth itself is. The technique of dating the age of rocks is known as radiometric dating:

https://en.wikipedia.org/wiki/Radiometric_dating.

For specifics of how the rocks are used to evaluate the age of the earth, please see this article:

https://en.wikipedia.org/wiki/Age_of_the_Earth, which gives much more detail on the geological calculations used in this science. 

 You might also be interested in this recent data from National Geographic:

http://news.nationalgeographic.com/news/2014/02/140224-oldest-crust-australia-zircon-science/, 

which finds the Earth to be 4.4 Billion years old (4400 000 000).

Kind regards,

Victoria

Public Information Volunteer
David Suzuki Foundation
219 – 2211 West 4th Avenue
Vancouver, BC V6K 4S2
604-732-4228
www.davidsuzuki.org

oldest rocks

Canadian researchers have discovered the oldest rocks in the world. The remnants of the Earth's early crust are 4.28 billion years old and were found in a belt of ancient bedrock in northern Quebec, along the eastern shore of Hudson Bay. More.