Carbon has a weight of twelve atomic mass units (AMU’s), and is the building block of all organic matter (plants and animals). A small percentage of carbon atoms have an atomic weight of 14 AMU’s. This is carbon-14. Carbon-14 is an unstable, radioactive isotope of carbon 12. For every one trillion carbon-12 atoms, you will find one carbon-14 atom.
Carbon-14 is made when cosmic rays knock neutrons out of atomic nuclei in the upper atmosphere. These displaced neutrons, now moving fast, hit ordinary nitrogen (14N) at lower altitudes, converting it into 14C. Unlike common carbon (12C), 14C is unstable and slowly decays, changing it back to nitrogen and releasing energy. This instability makes it radioactive.
Plants utilize, or “breath in” carbon dioxide, then ultimately release oxygen for animals to inhale. The carbon-14 dioxide is utilized by plants in the same way normal carbon dioxide is. This carbon-14 dioxide then ends up in humans and other animals as it moves up the food chain.
Carbon-14, a radioactive isotope of carbon with a half-life of 5,730 years, is used to find the age of formerly living things through a process known as radiocarbon dating. The theory behind carbon dating is fairly simple. Scientists know that a small amount of naturally occurring carbon is carbon-14. Although carbon-14 decays into nitrogen-14 through beta decay, the amount of carbon-14 in the environment remains constant because new carbon-14 is always being created in the upper atmosphere by cosmic rays. Living things tend to ingest materials that contain carbon, so the percentage of carbon-14 within living things is the same as the percentage of carbon-14 in the environment. Once an organism dies, it no longer ingests much of anything. The carbon-14 within that organism is no longer replaced and the percentage of carbon-14 begins to decrease as it decays. By measuring the percentage of carbon-14 in the remains of an organism, and by assuming that the natural abundance of carbon-14 has remained constant over time, scientists can estimate when that organism died. For example, if the concentration of carbon-14 in the remains of an organism is half of the natural concentration of carbon-14, a scientist would estimate that the organism died about 5,730 years ago, the half-life of carbon-14.
OK, simple. Now lets look at why this dating method is said to have “significant uncertainty’s”
from the journal Radiocarbon: Conventional radiocarbon ages (CRA)
A CRA embraces the following recommended conventions:
- a half-life of 5568 years;
- ..
- the assumption that all C14 reservoirs have remained constant through time.
To clear up the date issue:
Originally a carbon-14 half-life of 5568±30 years was used, which is now known as the Libby half-life. Later a more accurate figure of 5730±40 years was determined, which is known as the Cambridge half-life. However, laboratories continue to use the Libby figure to avoid inconsistencies when comparing raw dates and when using calibration curves to obtain calendrical dates.
So sweet. no big deal. Just pointing that out. Anyway:
The proportions of C-14 in the atmosphere in historic times is unknown. The C-14:C-12 atmospheric ratio is known to vary over time.
Complicating things further, various plants have differing abilities to exclude significant proportions of the C-14 in their intake. This varies with environmental conditions as well. The varying rates at which C-14 is excluded in plants also means that the apparent age of a living animal may be affected by an animals diet. An animal that ingested plants with relatively low C-14 proportions would be dated older than their true age.
To make carbon-14 dating work, Dr. Libby also assumed that the amount of carbon-14 being presently produced had equaled the amount of carbon-12 – he assumed that they had reached a balance. The formation of carbon-14 increases with time, and at the time of creation was probably at or near zero. Since carbon-14 is radioactive, it begins to decay immediately as it’s formed. If you start with no carbon-14 in the atmosphere, it would take over 50,000 years for the amount being produced to reach equilibrium with the amount decaying. Currently the amount of carbon-14 in the atmosphere is only 78% what it would be if the earth were old.
Dr. Robert Lee. In 1981, he wrote an article for the Anthropological Journal of Canada, in which stated:
“The troubles of the radiocarbon dating method are undeniably deep and serious. Despite 35 years of technological refinement and better understanding, the underlying assumptions have been strongly challenged, and warnings are out that radiocarbon may soon find itself in a crisis situation. Continuing use of the method depends on a fix-it-as-we-go approach, allowing for contamination here, fractionation there, and calibration whenever possible. It should be no surprise then, that fully half of the dates are rejected. The wonder is, surely, that the remaining half has come to be accepted…. No matter how useful it is, though, the radiocarbon method is still not capable of yielding accurate and reliable results. There are gross discrepancies, the chronology is uneven and relative, and the accepted dates are actually the selected dates.”
The list of non-compliant dates from this method is endless. Most evolutionists today would conclude that carbon-14 dating is – at best – reliable for only the last 3000 to 3500 years. There is another reason that carbon-14 dating has yielded questionable results – human bias. 😉
Lastly:
Coal is mean to be millions of years old. Yet No source of coal has been found that completely lacks 14C.
I have a few more points to put in later on, but this is long enough for now.
seeking reality 