Why is radiometric dating of carbon not a useful means to determine the age of the earth
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This assumes of course that no daughter atoms Y existed in the original sample, nor that any contamination took place in between. Carbon-14 dating relies on the fact that due to incidence of cosmic rays on the earth's atmosphere, carbon-14 is constantly being made by reaction with nitrogen in the atmosphere. There are other dating techniques such as isochrons and discordia which avoid the need to estimate initial daughter product concentrations. So if we take a lava flow and date several minerals for which one knows the daughter element is excluded, we should always get the exact same date, and it should agree with the accepted age of the geological period. Coffin mentions that fission tracks can survive transport through lava, for example. When the isotope is halfway to that point, it has reached its half-life. This also means that plants and animals that lived in the past had less C-14 in them than do plants and animals today.

Carbon-14 is a method used for young less than 50,000 year old sedimentary rocks. But the rate of a large group of them is such at after 1. The straight lines, which seem to make radiometric dating meaningful, are easily assumed to be the result of simple mixing. An example of a U-Pb discordia age is shown in. If you find a rock whose radioactive material has a half life of one year and measure 3. He states that the number of dates within range are less than the number of anomalies, except for the Cenozoic and Cretaceous.

Any amounts chosen must be based on assumption. Thus, the Earth and the atmosphere now contain about equal amounts of 40Ar, and the total could be generated if the Earth contained only 170 ppm potassium and released half of its 40Ar to the atmosphere. At the temperature or pressure, collisions with stray cosmic rays or the emanations of other atoms may cause changes other than those of normal disintegration. The intercept of the line on the ordinate gives the isotopic composition of the initial strontium present when the rock formed. And the original amount of the mother element isn't needed, because you can determine the date of solidification by the ratio of mother to daughter. This conclusion was clearly stated by both Wasserburg and others and by Faure and Powell. This could cause trouble for Rb-Sr dating.

Similarly with various Uranium to Lead transitions. It would be difficult to measure the tiny changes in concentration that would suffice to make large changes in the radiometric ages over long time periods. The study of the Liberian diabase dikes, discussed above, is a good example of this practice. In fact the pre-Flood proportion of C-14 could have even been less than this. Radiometric Dating Is Not Inaccurate Perhaps a good place to start this article would be to affirm that radiometric dating is not inaccurate. Anyway, as for C14 dating in general, it seems clear that many, many results are much too young according to the standard view, and that explaining away one or two of them does not appreciably diminish the problem. In nearly every case, the measured K-Ar age was zero, as expected if excess argon is uncommon.

There is nothing wrong with these ages; they are consistent with the known geologic relations and represent the crystallization ages of the Canadian samples. Then the partial pressure of argon 40 in the magma will never decrease below p; excess argon 40 will remain dissolved in the lava or magma as it cools. There are many radiometric clocks and when applied to appropriate materials, the dating can be very accurate. It was found that the extent of the haloes around the inclusions varies over a wide range, even with the same nuclear material in the same matrix, but all sizes fall into definite groups. Thus any method based on simple parent to daughter ratios such as Rb-Sr dating is bound to be unreliable, since there would have to be a lot of the daughter product in the magma already.

After another half-life, one fourth of the original substance will remain. Since no one was there, no one knows for sure. In his book on prehistoric America, Ceram notes a classic case of the difficulties that befall C14 dating. Granting that U-238 has a half-life of 4. This paper also discusses Mount St. It is interesting that Woodmorappe 1979 gives a number of cases in which standard geological tests are ignored. Also bear in mind that not all fossils are remains of living matter, for example, a remnant of a hole dug by an insect or worm could be a fossil.

In a number of samples where the abundance of 204Pb was very low no attempt was made to measure the amount of it as the determination would be of no particular value. This may be the main reason why radiometric dating often gives vastly inflated age estimates. But there is more carbon in the atmosphere now than there was 4 thousand years ago. And let me recall that both potassium and argon are water soluble, and argon is mobile in rock. The use of radiometric dating in Geology involves a very selective acceptance of data.

With radiocarbon dating, we see that carbon-14 decays to nitrogen-14 and has a half-life of 5,730 years. The weighted mean of these two measurements is 11. I treated this issue of percentage of anomalies in considerable detail in my original Radiometric Dating Game article. This would make them appear old. Thus the assumption of immense ages has not been proven.

Coal is not water soluble at least, coal cars aren't covered, and no one seems to worry about thunderstorms dissolving the coal away , and wood is waterproof, so one would expect that coalified wood would also be waterproof. It seems very possible that spontaneous disintegration of radioactive elements are related to the action of cosmic rays and the rate of disintegration varying from century to century according to the intensity of the rays. See for the derivation of the equation to which Dalrymple refers. According to the geologic column used by evolutionary geologists, three of these samples would be classified as Eocene, three as Cretaceous, and four as Pennsylvanian. I do think that radiometric dating is an accurate way to date the earth, although I am a geochronologist so I have my biases. As a result, glauconite is used for dating only with extreme caution.