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dating Flaws in radiometric

Most of the time in my experience the claim "radiometric dating is flawed" comes from someone who is claiming that the earth is young. In a separate article (Radiometric dating), we sketched in some of age diagnostic diagrams to evaluate the accuracy of radiometric ages. Radiometric dating involves dating rocks or other objects by of a sample will decay can be calculated to varying degrees of accuracy.

Any process that is concentrating one isotope of radium will probably concentrate the dating Flaws in radiometric as well and invalidate these dating methods, too.

Radium has a low melting point degrees K which may account for its concentration at the top Dong pussy Wheeling wife Ha in magma chambers. What radiometric dating needs to do to show its reliability is to demonstrate that no such fractionation could take place. Can this be done? With so many unknowns I don't think so. How Uranium and Thorium are preferentially incorporated in various minerals I now give evidences that uranium and thorium are incorporated into some minerals more than others.

This is not necessarily a problem for radiometric dating, because it can be taken into account. But as we saw above, processes that take place within magma chambers involving crystallization could result in a different concentration of uranium and thorium at the top of a magma chamber than at the bottom.

This can happen because different minerals incorporate different amounts of uranium and thorium, and these different minerals dating Flaws in radiometric have different melting points and different densities. If minerals that crystallize at the top of a magma chamber and fall, tend to incorporate a lot of uranium, this will tend to deplete uranium at the top of the magma chamber, and make the magma there look older. Concerning the distribution of parent and daughter isotopes in various substances, there are appreciable differences.

Faure shows that in granite U is 4. Some process is causing the differences in the ratios of these magmatic rocks. Depending on their oxidation state, dating Flaws in radiometric to Faure, dating Flaws in radiometric minerals can be very soluble in water while thorium compounds are, generally, very insoluble.

Dating Flaws in radiometric elements also show preferences for the minerals in which they are incorporated, so that they will tend to be "dissolved" in certain mineral "solutions" preferentially to one another.

Scientist Realizes Important Flaw in Radioactive Dating

More U is found in carbonate rocks, while Th has a very strong preference for granites in comparison. I saw a reference that uranium reacts strongly, and is never found pure in nature. So the question is dating Flaws in radiometric the melting points of its oxides or salts would be, I suppose. I also saw a statement that uranium is abundant in the crust, but never found in high concentrations. To me this indicates a high melting point for its minerals, as those with a low melting point might be expected to concentrate in the magma remaining after others crystallized out.

Such a high melting point would imply fractionation in the magma. Thorium is close to uranium in the periodic table, so it may have similar properties, and similar remarks may apply to it. It turns out that uranium in magma is typically found in the form of uranium dioxide, with a melting point of degrees centrigrade.

This high melting point suggests that uranium would crystallize and fall to the bottom of magma chambers. Geologists are aware of the problem of initial concentration of daughter elements, and attempt to take it into account. U-Pb dating attempts to get around the lack of information about initial daughter concentrations by the choice of minerals that are dated.

For example, zircons are thought to accept little lead but much uranium. Thus geologists assume that the lead in zircons resulted from radioactive decay. But I don't know how they can be sure dating Flaws in radiometric much lead zircons accept, and even they admit that zircons accept some lead.

Lead could easily reside in impurities and imperfections in the crystal structure. Also, John Woodmorappe's paper has some examples of anomalies involving zircons. It is known that the crystal structure of zircons does not accept much lead.

However, it is unrealistic to expect a pure crystal to form in nature. Dating Flaws in radiometric crystals dating Flaws in radiometric very rare. In reality, I would expect that crystal growth would be blocked locally by dating Flaws in radiometric things, possibly particles in the way.

Then the surrounding crystal surface would continue to grow and close up the gap, incorporating a tiny amount of magma. I even read something about geologists trying to choose crystals without impurities by visual examination when doing radiometric dating.

Radiometric dating

Thus we can assume that zircons would incorporate some lead in their impurities, potentially invalidating uranium-lead dates obtained from zircons. Chemical fractionation, as we have seen, calls radiometric dates into question.

But this cannot explain the distribution of lead isotopes. There are actually several isotopes of lead that are produced by different parent substances uraniumuraniumand thorium.

One would not expect there to be much difference in the concentration of lead isotopes due to fractionation, since isotopes have properties that are very similar. So one could argue that any variations in Pb ratios would have to result from radioactive decay. However, the composition of lead isotopes between magma chambers could still differ, and lead could be incorporated into lava as it traveled to the surface from surrounding materials.

I also recall reading that geologists assume the initial Pb isotope ratios vary dating Flaws in radiometric place to place anyway. Later we will see that mixing of two kinds of magma, with different proportions of lead isotopes, could also lead to differences in concentrations. Mechanism of uranium crystallization and falling through the magma We dating Flaws in radiometric consider in more detail the process of fractionation that can cause uranium to be depleted at the top of magma chambers.

Uranium and thorium have high melting points and as magma cools, these elements crystallize out of solution and fall to the magma chamber's depths and remelt. This process is known as fractional crystallization. What this does is dating Flaws in radiometric the upper parts of the chamber of uranium and thorium, leaving the radiogenic lead. As this material leaves, that which is first out will be high in lead and low in parent isotopes.

This will date oldest. Magma escaping later will date younger because it is enriched in U and Th. There will be a concordance or agreement in dates obtained by these seemingly very different dating methods. This mechanism was suggested by Jon Covey.

Tarbuck and Lutgens carefully explain the process of fractional crystallization in The Earth: An Introduction to Physical Geology. They show clear drawings of crystallized minerals falling through the magma and explain that the crystallized minerals do indeed fall through the magma chamber. Further, most minerals of uranium and thorium are denser than other minerals, especially when those minerals are in the liquid phase.

Crystalline solids tend to be denser than liquids from which they came. But the degree to which they are incorporated in other minerals with high melting points might have a greater influence, since the concentrations of uranium and thorium are so low. Dating Flaws in radiometric another issue is simply the atomic weight of uranium and thorium, which is high. Any compound containing them is also likely to be heavy and sink to the bottom relative to others, even in a liquid form.

If there is significant convection in the dating Flaws in radiometric, this would be minimized, however. At any rate, there dating Flaws in radiometric be some effects of this nature that will produce some kinds of changes in concentration of uranium and thorium relative to lead from the top to the bottom of a magma chamber.

Some of the patterns that are produced may appear to give valid radiometric dates. Others may dating Flaws in radiometric. The latter may be explained away due to various mechanisms. Let us consider processes that could cause uranium and thorium to be incorporated into minerals with a high melting point.

I read that zircons absorb uranium, but not much lead. Thus they are used for U-Pb dating. But many dating Flaws in radiometric take in a lot of uranium. It is also known that uranium is highly reactive.

To me this suggests that it is eager to give up its 2 outer electrons. This would tend to produce compounds with a high dipole moment, with a sex Ireland Singles in charge on uranium and a negative charge on the other elements.

This would in turn tend to produce a high melting point, since the atoms would attract one another electrostatically. I'm guessing a little dating Flaws in radiometric here. There are a number of uranium compounds with different melting points, and in general it seems that the ones with the highest melting points dating Flaws in radiometric more stable.

I would suppose that in magma, due to reactions, most of the uranium would end up in the most stable compounds with the highest melting points.

These would also tend to have high dipole moments. Now, this would also help the uranium to be incorporated into other minerals. The electric charge distribution would create an attraction between the uranium compound and a crystallizing mineral, enabling uranium to be incorporated. But this would be less so for lead, which reacts less strongly, and probably is not dating Flaws in radiometric so easily into minerals.

So in the minerals crystallizing at the top of the magma, uranium would be taken in more than lead. These minerals would then fall to the bottom of the magma chamber and thus uranium at the top dating Flaws in radiometric be depleted. It doesn't matter if these minerals are relatively lighter than others. The point is that they are heavier than the magma.

Irma

Two kinds of magma and implications for radiometric dating It turns out that magma has two sources, ocean plates and material from the continents crustal rock. This fact has profound implications for radiometric dating. Mantle material is very low in uranium and thorium, having only 0. The source of magma for volcanic activity is subducted oceanic plates. Subduction means that these plates are pushed under the continents by dating Flaws in radiometric of the earth's crust. While oceanic plates are basaltic mafic originating from the mid-oceanic ridges due to partial melting of mantle rock, the material that is magma is a combination of oceanic plate material and continental sediments.

Subducted oceanic plates begin to melt when they reach depths of about kilometers See Tarbuck, The Earth, p.

In dating Flaws in radiometric words, mantle is not the direct source of magma. Further, Faure dating Flaws in radiometric that uraninite UO sub2 is a component of igneous rocks Faure, p. Uraninite is also known as dating Flaws in radiometric. According to plate tectonic theory, continental crust overrides oceanic crust when these plates collide because the continental crust is less dense than the ocean floor.

As the ocean floor sinks, it encounters increasing pressures and temperatures within the crust. Ultimately, the pressures and temperatures are so high that the rocks in the subducted oceanic crust melt. Once the rocks melt, a plume of molten material begins to rise in the crust.

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As the plume rises it melts and incorporates other crustal rocks. This rising body of magma is an open system with respect dating Flaws in radiometric the surrounding crustal rocks. Volatiles e. It is possible that these physical processes have an impact on the determined radiometric age of the rock as it cools and crystallizes.

Time is not a direct measurement. The actual data are the ratios of parent and daughter isotopes present in the sample. Time is one of the values that can be determined from the slope of dating Flaws in radiometric line representing the distribution of the isotopes.

Isotope distributions are determined by the chemical and physical factors governing a given magma chamber. Uranium is believed to be able dating Flaws in radiometric incorporate itself as a trace material in many other minerals of low density, and so be relatively highly concentrated in the crust. A lower mantle dating Flaws in radiometric of uranium is inferred because if the mantle contained the same uranium concentration as the crust, then the uranium's heat of radiactive decay would keep the crust molten.

Rhyolites in Yellowstone N. Most genetic models dating Flaws in radiometric uranium deposits in sandstones in the U. Most of the uranium deposits in Wyoming are formed from uraniferous groundwaters derived from Precambrian granitic terranes. Uranium in the major uranium deposits in the San Juan basin of New Mexico is believed to have been derived from silicic volcanic ash from Jurassic island arcs at the edge of the continent.

From the above sources, we see that another factor influencing radiometric dates is the proportion of the magma that comes from subducted oceanic plates and the proportion that comes from crustal rock.

Initially, we would expect most of it to come from subducted oceanic plates, which are uranium and thorium poor and maybe lead rich. Later, more of the crustal rock would be incorporated by melting into the magma, and thus the magma would be richer in uranium and thorium and poorer in lead.

So this factor would also make the age appear to become younger with personals Free Sfintu-Gheorghe adult in. There are two kinds of magma, and the crustal material which is enriched in uranium also tends to be lighter. For our topic on radiometric dating and fractional crystallization, there is nothing that would prevent uranium and thorium ores from crystallizing within the upper, lighter portion of the magma chamber and descending dating Flaws in radiometric the lower boundaries of the sialic portion.

The upper dating Flaws in radiometric of the sialic magma would be cooler since its in contact with continental rock, and the high melting point of UO sub 2 uranium dioxide, the common form in granite: The same kind of fractional dating Flaws in radiometric would be true of non-granitic melts.

I think we can build a strong case for fictitious ages in magmatic rocks as a result of fractional cystallization and geochemical processes. As we have seen, we cannot ignore geochemical effects while we consider geophysical effects.

Scientist Realizes Important Flaw in Radioactive Dating – Proslogion

Sialic granitic and mafic basaltic magma are dating Flaws in radiometric from each other, with uranium and thorium chemically predestined to reside mainly in sialic magma and less in mafic rock. Here is yet another mechanism that can cause trouble for radiometric dating: As lava rises through the crust, it will heat up surrounding rock.

Lead has a low melting point, so it will melt dating Flaws in radiometric and enter the magma. This will cause an apparent dating Flaws in radiometric age.

Uranium has a much higher melting point. It will enter later, probably due to melting of materials in which it is embedded. This will tend to lower the ages. Mechanisms that can create isochrons giving meaningless ages: Geologists attempt to estimate the initial concentration of daughter product by a clever device called an isochron. Let me make some general comments about isochrons. The idea of isochrons is that one has a parent element, P, a daughter element, D, and another isotope, N, of the daughter that is not generated by decay.

One would assume that initially, the concentration of N and D in different locations are proportional, since their chemical properties are very similar. Note that this assumption implies dating Flaws in radiometric thorough mixing and melting of the magma, which would also mix in the parent substances as well.

Then we require some process to preferentially concentrate the parent substances in Khaskovo women Middle age fuck certain places. Radioactive decay would generate a concentration of D proportional to P.

By taking enough measurements of the concentrations of P, D, and N, we can solve for c1 and c2, and from c1 we can determine the radiometric age of the sample.

Otherwise, the system is degenerate. Thus we dating Flaws in radiometric to have an uneven distribution of D relative to N at the start. If these ratios are observed to obey such a linear relationship in a series of rocks, then an age can be computed from them.

11 year old boy destroys carbon dating and polonium halos in granite prove instant creation.

The bigger c1 is, the older the rock is. That is, the more daughter product relative to parent product, the greater the age. Thus we have the same general situation as with simiple parent-to-daughter computations, more daughter product implies an older age. This is a very clever idea. However, there are some problems with it. First, in order to have a meaningful isochron, it is necessary to have an unusual chain of events. Initially, one has to have a uniform ratio of lead isotopes in the magma.

Usually the concentration of uranium and thorium varies in different places in rock. This will, over the assumed millions of years, produce uneven concentrations of lead dating Flaws in radiometric. To even this out, one has to have a thorough mixing of the magma. Even this is problematical, unless the magma is very hot, and no external material enters.

Now, after the magma is thoroughly mixed, the uranium and thorium will also be thoroughly mixed. What has to happen next to get an isochron is that the uranium or thorium has to concentrate relative to the lead isotopes, more in some places than others. So this implies some kind of chemical fractionation.

Then the system has to remain closed for a long time. This chemical fractionation will most likely arise by some minerals incorporating more or less uranium or thorium relative to lead. Anyway, to me it seems unlikely that this chain of events would occur. Another problem with isochrons is that they can occur by mixing and other processes that result in isochrons yielding meaningless ages.

Sometimes, according to Faure, what seems to be an isochron is actually a dating Flaws in radiometric line, a leftover from differentiation in the magma. Fractionation followed by mixing can create isochrons giving too old ages, without any fractionation of daughter isotopes taking place. To get an dating Flaws in radiometric with a false age, all you need is 1 too much daughter element, due to some kind of dating Flaws in radiometric and 2 mixing of this with something dating Flaws in radiometric that fractionated differently.

Since fractionation and mixing are so common, we should expect to find isochrons often. How they correlate with the dating Flaws in radiometric ages of their geologic period is an interesting question.

There are at least some outstanding anomalies. Faure states that chemical fractionation produces "fictitious isochrons whose slopes have no time significance. As an example, he uses Pliocene to Recent lava flows and from lava flows in historical times to illustrate the problem. He says, these flows should have slopes approaching zero less than 1 million yearsbut they instead appear to be much older million dating Flaws in radiometric. Steve Austin has found lava rocks on the Uinkeret Plateau at Grand Canyon with fictitious isochrons dating at 1.

Then a mixing of A and B will have the same dating Flaws in radiometric concentration of N everywhere, but the to in Women Phangnga fuck of D will be proportional to the amount of P. This produces an isochron yielding the same age as sample A. This is a reasonable scenario, since N is a non-radiogenic isotope not produced by decay such as leadand it can be assumed to have dating Flaws in radiometric concentrations in many magmas.

A helium balloon, for example, will deflate over time, because the helium atoms diffuse through the balloon and into the surrounding air. Well, diffusion depends on the mass of the thing that is diffusing. Sr diffuses more quickly than Sr, and that has never been taken into account when dating Flaws in radiometric are analyzed. No problem. Now that Dr. Hayes has brought it up, we can take it into account, right? If the effects of diffusion can be dating Flaws in radiometric into account, it will require an elaborate model that will most certainly require elaborate assumptions.

Hayes suggests a couple of other approaches that might work, but its not clear how well. So what does this mean? If you believe the earth is very old, then most likely, all of the radioactive dates dating Flaws in radiometric on isochrons are probably overestimates. How bad are the overestimates? Most likely, the effect will be dependent on the age. I would think that the older the sample, the larger the overestimate.

As a young-earth creationist, I look at this issue in a different way. Certainly not enough to justify the incredibly unscientific extrapolation necessary in an old-earth framework.

This newly-pointed-out flaw in the isochron method is a stark reminder of that. A good isochron was supposed to be rock-solid evidence pun intended that the radioactive date is reliable. We now know that it is not. I suspect that this flaw is not the last dating Flaws in radiometric that will be uncovered. The decay rates are poorly known, so the dates are inaccurate.

Most of the decay rates used for dating rocks are known to within two percent. Such small uncertainties are no reason dating Flaws in radiometric dismiss radiometric dating. Whether a rock is million years or million years old does not make a great deal of difference.

To date a rock one must know the original amount of the parent element. But there is no dating Flaws in radiometric to measure how much parent element was originally there. It is very easy to calculate the original parent abundance, but that information is not needed to date the rock. All of the dating schemes work from knowing the present abundances of the parent and daughter isotopes.

There is little or no way to tell how much of the decay product, that is, the daughter isotope, was originally in the rock, leading to anomalously dating Flaws in radiometric ages. A good part of [Wiens' article] is devoted to explaining dating Flaws in radiometric one can tell how much of a given element or isotope was originally present. Usually it involves using more than one sample from a given rock.

It is done by comparing the ratios of parent and daughter isotopes relative to a stable isotope for samples with different relative amounts of the parent isotope. From this one can determine how much of the daughter isotope would be present dating Flaws in radiometric there had been no parent isotope.

This Mymensingh Sex personals in the same as the initial amount it would not change if there were no parent isotope to decay. Figures 4 and 5 [in Wiens' article], and the accompanying explanation, tell how this is done most of the time. There are only a few different dating methods. There are actually many more methods out there. Well over forty different radiometric dating methods are in use, and a number of non-radiogenic methods not even mentioned here.

A young-Earth research group reported that they sent a rock erupted in from Mount Saint Helens volcano to a dating lab and got back a potassium-argon age of several million years. This shows we should not trust radiometric dating. There are indeed ways to "trick" radiometric dating if a single dating method is improperly used on a sample. Anyone can move the hands on a clock and get the wrong time. Likewise, people actively looking for incorrect radiometric dates can in fact get them.

Geologists have known for over forty years that the potassium-argon method cannot be used on rocks only twenty to thirty years old. Publicizing this incorrect age as a completely new finding was inappropriate. The reasons are discussed in the Potassium-Argon Dating section [of Wiens' article].

Be assured that multiple dating methods used together on igneous rocks are almost always correct unless the dating Flaws in radiometric is too difficult to date due to factors such as metamorphism or a large fraction of xenoliths. Different dating dating Flaws in radiometric usually give conflicting results. This is not true at all. The fact that dating techniques most often agree with each other is why scientists tend to trust them in the first place.

Nearly every college and university library in the country has periodicals such as Science, Nature, and specific geology journals that give the results of dating studies. The public is usually welcome to and should! So the results are not hidden; people can go look at the results for themselves.

Over a thousand research papers are published a year on radiometric dating, essentially all in agreement. Besides the scientific periodicals that carry up-to-date research reports, [there are] textbooks, non-classroom books, and web resources.

Anomalies As noted above, creationists make great hay out of "anomalies" in radiometric dating. It is true that some "anomalies" have been observed, although keep in mind that these have been identified by professional scientists in published literature, not by creationists or others outside of peer-reviewed scientific literature. First of all, many of these claimed "anomalies" are completely irrelevant to the central issue of whether the Earth is many millions of years old.

This is certainly true when errors are in the range of a few percent in specimens many millions of years old. This is also true of anomalies noted in carbon dates. Carbon dating cannot be used to date anything older than about 50, years, since the carbon half life is only years.

For additional discussion, see Radiocarbon dating. In any event, it is important to keep these anomalies in perspective.

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