How is carbon dating proved to be accurate?

Question

Who was around 3,000,000 years ago to validate the carbon dating test?

Answer 1

Radiometric dating, of which carbon dating is a type, is done this way (this is a fairly dumbed down version):

We know, through experiments, the rate at which isotopes of elements decay. All organisms take in carbon-14 during their lives. When they die they stop taking more in and what is in their body begins to decay. We can then examine a sample (from say a bone) and determine how far along the decay is and that tells us how long it has been since the organism it was obtained from died.

Carbon dating is not reliable for anything older than about 60,000 years. For things of great age, such as rocks, other forms of dating are used such as potassium-argon.

Answer 2

There are times when we know the date of a particular sample through other means and these dates have been confirmed by carbon dating.  There are some limitations and it isn't perfect but it is a good way to date items less than 50,000 years old.  

Answer 3

A typical question asked by someone who has no interest in the answer. It is just a method of putting forward his uneducated misconceptions to get a reaction.

Answer 4

Radiocarbon dating techniques, first developed by the American chemist Willard F. Libby and his associates at the University of Chicago in 1947, are frequently useful in deciphering time-related problems in archaeology, anthropology, oceanography, pedology, climatology, and recent geology. Through metabolic activity, the level of carbon-14 in a living organism remains in constant balance with the level in the atmosphere or some other portion of the earth’s dynamic reservoir, such as the ocean. Upon the organism’s death, carbon-14 begins to disintegrate at a known rate, and no further replacement of carbon from atmospheric carbon dioxide can take place. The rapid disintegration of carbon-14 generally limits the dating period to approximately 50,000 years, although the method is sometimes extended to 70,000 years. Uncertainty in measurement increases with the age of the sample.

Although the method is suited to a variety of organic materials, accuracy depends on the half-life to be used, variations in levels of atmospheric carbon-14, and contamination. (The half-life of radiocarbon was redefined from 5570 ± 30 years to 5730 ± 40 years in 1962, so some dates determined earlier required adjustment; and due to radioactivity more recently introduced into the atmosphere, radiocarbon dates are calculated from ad 1950.) The radiocarbon time scale contains other uncertainties, as well, and errors as great as 2000 to 5000 years may occur. Postdepositional contamination, which is the most serious problem, may be caused by percolating groundwater, incorporation of older or younger carbon, and contamination in the field or laboratory.

Thus, we can't say that carbon dating testing is that accurate...and its impossible to use carbon dating within a period of 3,000,000 years, since it's limited to 50,000 to 70,000 years only.

Answer 5

The carbon in the atmosphere normally combines with oxygen to make carbon dioxide (CO2). Plants breathe CO2 and make it part of their tissue. Animals eat the plants and make it part of their tissues. A very small percentage of the carbon plants take in is radioactive C-14. When a plant or animal dies it stops taking in air and food so it should not be able to get any new C-14. The C-14 in the plant or animal will begin to decay back to normal nitrogen. The older an object is, the less carbon-14 it contains. One gram of carbon from living plant material causes a Geiger counter to click 16 times per minute as the C-14 decays.

Answer 6

Carbon dating has agreed well with tree ring and varve,

(seasonal lake sediment deposit), dating when comparisons

were available.

It doesn't go back 3 mil. Yr.s though.