carbon dating is not used for fossiles, it is used for dating younger items (not older than 30 000 years AFAIK)
Some of the oldest rocks on earth are found in Western Greenland. Because of their great age, they have been especially well studied. The table below gives the ages, in billions of years, from twelve different studies using five different techniques on one particular rock formation in Western Greenland, the Amitsoq gneisses.
Technique Age Range (billion years)
uranium-lead 3.60±0.05
lead-lead 3.56±0.10
lead-lead 3.74±0.12
lead-lead 3.62±0.13
rubidium-strontium 3.64±0.06
rubidium-strontium 3.62±0.14
rubidium-strontium 3.67±0.09
rubidium-strontium 3.66±0.10
rubidium-strontium 3.61±0.22
rubidium-strontium 3.56±0.14
lutetium-hafnium 3.55±0.22
samarium-neodymium 3.56±0.20
(from:
http://www.asa3.org/ASA/resources/Wiens.html Radiometric Dating - A Christian Perspective)
more at:
http://www.talkorigins.org/faqs/dating.html