Radiocarbon Dating

Radiocarbon dating is a chemical analysis used to determine the age of organic materials based on their content of the radioisotope carbon-14, to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Archaeology and other human sciences use radiocarbon dating to prove or disprove theories. Over the years, carbon 14 dating has also found applications in geology, hydrology, geophysics, and atmospheric science. Not all materials can be radiocarbon dated. Most, if not all, organic compounds can be dated. Samples that have been radiocarbon dated since the inception of the method include charcoal, wood, twigs, seeds, bones, shells and water, among others. When plants during photosynthesis they include a certain amount of 14C, the isotope in the atmosphere matches the same level approximately. Through photosynthesis Carbon dioxide is taken in by the plant, which is also ingested by animals, therefore every living organism is continually exchanging carbon-14 with its surrounding area as long as it lives. On the other hand when the organism dies the exchanges stops, so the amount of carbon-14 slowly decreases by radioactive beta decay with a half-life of 5,730+-40 years, half-life is the period of time it takes for the amount of a substance undergoing decay to decrease by half.

There are three main types of techniques which are used to measure carbon-14 content of any given sample: gas proportional counting, liquid scintillation counting, and accelerator mass spectrometry. Firstly counting proportional counting is a conventional radiometric dating technique, which counts the quantity of beta particles that are produced by a given sample. A product of radiocarbon decay is beta particles. Measurement of the carbon in the gas proportional counters takes place after it is converted to carbon dioxide. Secondly there liquid scintillation counting which is another radiocarbon dating technique, this was well known in the 1960s.In the process of this method the sample is presented in a liquid form then a scintillator is added. Furthermore the scintillator produces a flash of light when it meets with a beta particle. Between two photomultipliers a sample passed between them, the count can only be made when both devices register the flash of light. The last technique is accelerator mass spectrometry, which is a modern technique of radiocarbon dating method, it is seen as the most effective way of measuring radiocarbon content. This method does not count the beta particles however it does of the number of carbon atoms, the carbon 14 is measured directly unlike the carbon 12 and 13.

|TABLE 1 Age Determinations on Samples of Known Age |
|Sample |Specific activity |Age (years) |
| |(cpm/g of carbon) | |
| |Found |Expected |Found |Expected |
|Tree Ring |11.10 ±0.31 |10.65 |1100 ±150 |1372 ±50 |
| |11.52 ±0.35 | | |(577±50 A.D.) |
| |11.34 ±0.25 | | | |
| |10.15 ±0.44 | | | |
| |11. 08 ±0.31 | | | |
| |Average : 10.99 ±0.15 | | | |
|Ptolemy |9.5 ±0.45 |9.67 |2300 ±450 |2149 ±150 |
| | | | |(200 ±150 B.C.) |
|Tayinat |8.97 ±0.31 |9.10 |2600 ±150 |2624 ±50 |
| |9. 03 ±0.30 | | |(675 ±50 B.C.) |
| |9.53 ±0.32 | | | |
| |Average: 9.18 ±0.18 | | | |
|Redwood |8.81 ±0.26 |8.78 |3005 ±165 |2928 ±52 |
| |8.56 ±0.22 | | |(979 ±52 B.C.) |
| |Average : 8. 68 ±0.17 | | | |
|Sesostris |7.73 ±0.36 |7.90 |3700 ±400 |3792 ±50 |
| |8. 21 ±0.50 | | |(1843 ±50 B.C.) |
| |Average : 7.97 ±0.30 | | | |
|Zoser : Sneferu |7.88 ±0.74 |7.15 |4750 ±250 |4650 ±75 |
|Zoser |7.36 ±0.53 | | |(2700 ±75 B.C.) |
|Sneferu |6.95 ±0.40 | | |4575 ±75 |
| |7.42 ±0.38 | | |(2625 ±75 B.C.) |
| |6.26 ±0.41 | | |Average: |
| |Average: | | |4600 ±75 |
| |7.04 ±0.20 | | |(2650 ±75 B.C.) |

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The studies by Rutherford and Holmes on the age of the earth by radiometric dating. Radiometric dating has been ongoing since the year 1905; it was invented by Ernest Rutherford a method that might possibly determine the age of the earth. Radiometric dating is a method used to age materials such as rocks etc. it is the principal source of information about the absolute age of rocks and other geological features, this includes the age of the earth, furthermore it can be used to date a variety of natural and man-made materials.

The possible conflicts between religious beliefs, some Christians believe that "Outside the range of recorded history, calibration of the 14C clock is not possible." This was true back in the 1950s. A team of researchers, headed by Willard F. Libby calibrated the C-14 measuring technique by comparing the measured age of samples from ancient Egypt with their known date. For example, they tested a piece of wood from Pharaoh Zoser's tomb with the known tomb date, which was known to be circa 2700 to 2600 BCE. The agreement was excellent. Since then, extended calibration checks have been made using U.S. bristlecone pine, German and Irish oak, and other species of trees. That work pushed the calibration back well beyond recorded history to 10,000 BP other correlations have extended that to 26,000 years BP. It may eventually go back as far as 45,000 years, which is the approximate limit of the C-14 technique. Christians also believe that The flood of Noah, as described in Genesis, Chapter 6 to 8, would have upset the carbon balance on earth by burying large amounts of carbon containing plants which became coal, and gas. This would lower the total C-12 in the atmosphere at that time and upset the C-14 dating process. The Genesis flood is described in Genesis as occurring circa 2349 BCE. Samples from Egypt before, during and after the flood whose dates are precisely known have been C-14 dated without any difficulty. Either the worldwide flood of Noah did not happen, or it did not create any significant disturbance in the C-12/C-14 balance at the time. Again, if it did have an effect, it would be corrected by the calibration process. Furthermore Volcanoes emit a great deal of carbon dioxide which contains very little C-14. Since a massive degree of volcanism occurred during the flood of Noah, objects which died shortly after the flood would give inaccurate C-14 dating results. Again, C-14 dating results on Egyptian samples before, during and after the flood were found to be accurate when the data was compared with the actual dates as independently obtained. If there were a great deal of volcanism in the 23rd century BCE, it does not show up in the C-14 data.

The evidence from the use of these dating methods. Is it reliable and valid? The accuracy of this method, however mainly relies on many imperfect assumptions. Firstly for c14 dating to be accurate, however the rate of decay for the carbon-14 has remained steady during the years. On the other hand the evidence shows us that the opposite is true. The radioactive isotopes of Uranium-238 and iron-57, experiments have been carried out with them, also change in the surrounding environment which can alter decay rates. Secondly the faulty assumption is that the rate of carbon-14 formation has remained the same over many years that have gone past. There are quite a few reasons to believe this statement is flawed. The amount of carbon-12 has greatly increased over the years because an increase in the industrial revolution through the burning of coal. In 1950 there was an increase carbon-14 concentrations, this was caused by an atomic bomb testing around the 1950s. Moreover, for the carbon-14 to be more precise and accurate, both concentrations of carbon-12 and 14 must have remained persistent in the atmosphere. However the great flood which Noah and his family survived provides another piece of evidence that it is an incorrect statement. This is because during the flood subterranean water chambers would have been penetrated because of all the pressure, therefore the outcome would be that immense quantity of carbon-12 would be released into the ocean and atmosphere. There would have been an upset on the ration of carbon-14 and 12. Carbon dating is reliable for 50-60,000 years back. Beyond that, there isn't enough radiocarbon left to tell much. Carbon dating has been shown to be reliable by comparing the age of materials from means other than carbon dating with age determined by carbon dating. For example, we might know the age of a coin because of the minting. If we also figure out the age by carbon dating and we compare those numbers, we can "test" the carbon dating method. It has proven to be very reliable. In those instances where it breaks down, it is for reasons that make sense. Also Dr. Libby assumed to make carbon-14 dating work the amount of carbon-14 being produced up-to-date had equaled the amount of carbon-12, thus he expected they had reached a balance. At the time of creation carbon-12 was at or near 0 and gradually increases along with time, however because it is radioactive, as soon as it is formed it will decay thus if you start with nothing it will take you more than 50,000 years for there to be an equilibrium.

|Reference |Source |Reliability |
|1 |www.unmaskingevolution.com/1-carbon14.htm |22/04/2012 |
|2 |www.religioustolerance.org/c14datc.htm |25/04/2012 |
|3 |www.radiocarbon.com/about-carbon-dating.htm |25/04/2012 |
|4 |www.c14dating.com/int.html |23/04/2012 |
|5 |http://christiananswers.net/ |24/04/2012 |
|7 |www.allaboutcreation.org/radiometric-dating.htm |23/04/2012 |
|8 |http://www.c14dating.com/k12.html |26/04/2012 |
|9 |Age determinations by radiocarbon content: checks with |Arnold, J.R.; Libby, W.F. (1949) |
| |samples of known age | |
|10 |www.chcpublications.net/radcarbn.htm |25/04/2012 |