I personally don't believe the earth or it's inhabitants have only been around 6K years. For those who believe the earth is roughly 6K years or 10K years old, have you ever read about ice core dating? Basically we can extract large tubes of ice from the polar caps and analyze them...we can see "rings" which stand for annual snowfall.
They also use other dating methods as you go farther back in time since the ice gets compressed and the rings are no longer visible. Scientists have dated ice cores in the tens of thousands or even hundreds of thousands of years.
Just thought this would be an interesting discussion.
I edited my message because I wanted to post a link to a site that explains what I'm talking about in better detail.
This link is an article on ice core dating from Manchest University:
http://www.doc.mmu.ac.uk/aric/gccsg/3-3-2-3.html