Ra on the Easter Island Heads and Nazca Lines

[MangusKhan]

Radiocarbon dating is only useful for determining the age of organic substances. So if we're talking about a giant stone head, or massive drawings in the earth, then I'm not sure how you could use the process of organic radioactive decay to put an age on the structures themselves. Obviously if you try to use carbon dating to find the age of the organic remnants in the area, you will just find the date of the last group of people who lived there.

I have to say though, for drawings supposedly made by advanced extraterrestrials, those Nazca figures are pretty sloppy.