Unreliability of Radiometric Dating and Old Age of the Earth
The textbooks speak of the radiometric dating techniques, and the dates Carbon dating can be used to find the ages of some items. time if you know several things: the amount of sand in the top of the hourglass when it. The carbon-dating process that dated Stonehenge to about B.C. was conducted by the technique's godfather, Willard Libby. \[ Snow Can't Stop the Edward Scissorhands of Flying Cars Nope, Just Good Ol' Fashioned Physics transmitted, cached or otherwise used, except with the prior written. Radiometric dating methods estimate the age of rocks using .. Slusher asserted that the best known value of the branching ratio was not always used in Coal is not water soluble (at least, coal cars aren't covered, and no.
The dates obtained by different radiometric isotope pairs cross-check each other. For the purposes of assessing accuracy, each of the methods is assumed to be applied in accordance with the established methods and technology. By analogy, a stop watch will not keep accurate time if it is not wound, if it is not in good repair, or if the operator forgets to press the button.
Methods are precise insofar as they are properly used. Anyone questioning the accuracy of radiometric methods is obliged to explain why the cross-checks to sediments, coral growth, tree rings, and other isotope pairs all have the same errors. Why would an error in radiometric dating correspond to errors in the other methods so that they all track? In fact, they track because radiometric data is accurate. An expert scientist summarizes: Since then, geologists have made many tens of thousands of radiometric age determinations, and they have refined the earlier estimates.
A key point is that it is no longer necessary simply to accept one chemical determination of a rock's age. Age estimates can be cross-tested by using different isotope pairs.
- Radiometric Dating is Accurate
- Radiometric dating
- Assumptions of Radioactive Dating
Results from different techniques, often measured in rival labs, continually confirm each other. Every few years, new geologic time scales are published, providing the latest dates for major time lines. Older dates may change by a few million years up and down, but younger dates are stable. For example, it has been known since the s that the famous Cretaceous-Tertiary boundary, the line marking the end of the dinosaurs, was 65 million years old.
Repeated recalibrations and retests, using ever more sophisticated techniques and equipment, cannot shift that date. It is accurate to within a few thousand years. The resolution is affirmed. However, I want to be clear that my goal here is not to "prove" young earth creationism, but to simple show that radiometric dating of the age of the earth is unreliable. The measurement of time by radioactive decay of a parent isotope is often compared to the measurement of time as sand grains fall in an hour glass: The sand grains fall from the upper chamber at a constant rate, said to be analogous to radioactive decay.
If all the sand grains started in the upper chamber and then the number of sand grains were measured in the two chambers after some time elapsed, provided the rate at which the sand grains fall has been measured, simple mathematics can be used to calculate how long the hourglass has been in operation, and thus, the time when the process started.Minivans - top choices - Consumer Reports
When applied to the radioactive decay "clock," this starting time is when the rock formed and is, therefore, its calculated age. The number of atoms of the daughter isotope originally in the rock or mineral when it crystallized can be known. In other words, it is assumed that we can know the initial conditions when the rock or mineral formed.
The number of atoms of the parent and daughter isotopes have not been altered since the rock or mineral crystallized, except for radioactive decay.
The rate of decay of the parent isotope is known accurately, and has not changed during the existence of the rock or mineral since it crystallized. Thus, it logically follows that these assumptions are, strictly speaking, not provable.
Potassium-Argon and Argon-Argon Methods Both these methods suffer from the same problems, because they are both based on the radioactive decay of potassium K to argon Ara gas which does not bond with other elements. As my opponent pointed out it is assumed the initial quantity of the daughter isotope Ar is not needed because it does not bond easily with other elements and, therefore, when the rock forms all the initial Ar would have escaped.
In other words, it is assumed there was no initial Ar at the time of formation. However, many cases have been documented of recent historic lava flows which yielded grossly incorrect K-Ar ages because of "excess argon.
Helens a new lava dome began forming. Inless than ten years after it flowed and cooled, dacite lava from this dome was sampled and analyzed . Similarly, andesite from the lava flow from Mt. The diamonds could not be older than the earth itself! The obvious conclusion most investigators have reached is that excess argon had to be present and they did not completely degas when these rocks and diamonds formed.
Even laboratory experiments have shown that argon can be retained in rocks and mineral at the time of formation . There is also much evidence for argon loss for the very fact Ar does not form chemical bonds with other atoms in a crystal lattice, but lack of space does not permit me to go into detail [5, 6].
Radiocarbon Dating Method There are two basic assumptions in C dating. First, the cosmic ray influx has to have been essentially constant my opponent already mentioned this and the C concentration in the carbon dioxide cycle must remain constant. To these two assumptions we can add the assumption of the constancy of the rate of decay of C, the assumption that dead organic matter is not later altered with respect to its carbon content by any biologic or other activity, the assumption that the carbon dioxide contents of the ocean and atmosphere has been constant with time, the assumption that the huge reservoir of oceanic carbon has not changed in size during the period of applicability of the method, and the assumption that the rate of formation and the rate of decay of radiocarbon atoms have been in equilibrium throughout the period of applicability.
Nevertheless, it has been maintained that the method has been verified beyond any question by numerous correlations with known dates. However, closer investigation reveals that where historical dates are well established, back beyond about BC, the radiocarbon "dates" increasingly diverge, as they also do from tree-rings even though my opponent said they correlate with tree-rings .
So the major assumptions in the method would, therefore, appear to be valid for only the period after BC. Furthermore, my opponent asserted, regarding C dating, "After a long enough time the minority isotope is in an amount too small to be measured. My opponent, therefore, must explain the substantial amount of C found in coalfields that are millions of years old and diamonds that are billions of years old.
Recently, ten coal samples representative of the economic important coalfields of the United States, and five diamonds from African kimberlite pipes were analyzed . Three of the coal samples were from Eocene seams, three from Cretaceous seams, and four from Pennsylvania seams Uniformitarian ages ranging from 40 Ma to Ma.
Yet they all yielded dates around 50, years. The diamonds came from underground mines where contamination would be minimal. However, diamonds are the hardest natural mineral and extremely resistant to contamination. These diamonds are considered to be billion years old according to uniformitarian geologists, so they should have been radiocarbon-dead. Nevertheless, they still contained significant levels of C Given the supposed antiquity of these diamonds, and their source deep inside the earth, one possible explanation for these detectable C levels is that the C is primordial.
However, if this were the case, the apparent "age" of the earth itself would only be about 45, years old according to my opponent! The presence of detectable C in fossils, which according to the uniformitarian timescale should be entirely Cdead, has been reported from the earliest days of radiocarbon dating.
For example, a published survey on all the dates reported in the journal "Radiocarbon" up to commented that for more than 15, samples reported: This data shows that radiometric dating is unreliable and questionable at best.
I have many more examples to share, but space does not permit. I will elaborate in further rounds and I hope to address Pros assertion that independent dating methods correlate with the radiometric dates. Although, by showing that radiometric dating is unreliable on its own terms, any perceived correlation with independent dating methods means absolutely nothing. My sources are in the comment section. Con has only provided evidence that argon dating has some undefined error in some cases, and that a few cases of carbon dating are in error.
He offers some unrefereed papers by avowed creation scientists that there are broader problems, but even in those claims, there is nothing that questions the overall statistical accuracy. The arguments are akin to claiming that a wristwatch cannot be used to measure time, because sometimes the battery fails or the display is misread. Errors do happen, but they are well within the claimed error bounds and they are limited by cross-checking.
With a wristwatch you check with a different clock, with radiometric dating the checks are with different dating methods and different isotope pairs. Con claims that we cannot know with certainty what the composition of an original sample was. Absolute certainty is not required. Assumptions are made based upon observations. The reliability of the assumptions is ultimately tested by crosschecking to independent dating methods.
Radiometric dating is known to be accurate not because it is assumed to accurate, but rather by cross-checking and proving it is accurate. Con is correct that rock samples selected for argon dating cannot have been exposed to air.
That is true not only for recent volcanic flows, but with old rocks have fissures allowing air intrusions. One technique is to rely on feldspars formed only at very high temperatures.
The error due to air exposure always makes the sample appear younger than it really is. Different grains of rock from the same location may have different exposures to the air due to the pattern of fissures, so a cross-check is to test several samples to ensure a reliable result.
In the opening round, I made the caveat that the methods are only accurate when properly applied. There are also a dozen isotope pairs that cross-check argon dating. The reliability of the dating is further enhanced by cross-checking in the same sample. Snelling as to the general unreliability of argon dating. The article cited is in a religious journal, not in a peer-reviewed scientific journal.
Snelling is a legitimate scientist who also publishes in peer-reviewed journals. However, he writes in the scientific literature he accepts the accuracy of the standard scientific dating methods. When he writes for his religious audience he denies them.
If he had data that would withstand scientific scrutiny, he would publish it in scientific journals. Clearly he does not. Con points out the problem with carbon dating of coal and diamonds. The problem is well known. Coal contains radioactive thorium, and the thorium creates C14 in situ.
As a known limitation, it is not particularly troublesome. It is comparable to knowing that a wristwatch won't work properly in high magnetic fields; once one is aware of that, it is readily avoided. Con claims that there is some general problem with the accuracy of carbon dating for dates after BC.
Con quotes Whitelaw, a creationist published by a religious press, not by a peer-reviewed scientific journal. Whitelaw supposes that there was no C14 in the atmosphere more than years ago, so when he scales all the dates according to his theory they are all within 50, years. Aside from the theory having no scientific foundation, it is contradicted by all the dating methods that cross-reference carbon dating.
One must suppose that trees grew exponentially slower in the past, and so forth, to produce exactly the same errors as the error he supposes. Con cites Bowman, a scientist who vigorous supports the accuracy of carbon dating.
The British Museum lab doing carbon dating made some errors during the period from Bowman discovered and corrected the errors. There was no general problem with radiocarbon dating. In the book by Bowman cited by Con, Bowman writes of errors less than 50 years as relatively easy to achieve, and less than 20 years possible with great care. That was written in Throughout, Con has refused to confront the central proof that radiometric dating is accurate.
That proof is that the dates arrived by radiometry are verified by dendrochronology tree ringsvarve chronology sediment layersice cores, coral banding, speleotherms cave formationsfission track dating, and electron spin resonance dating.
The dates are also verified by independent measurements from other isotope pairs. In R1 I presented the challenge to him, "Anyone questioning the accuracy of radiometric methods is obliged to explain why the cross-checks to sediments, coral growth, tree rings, and other isotope pairs all have the same errors. Suppose we suspect that Cousin Lenny's watch is in error. How do we verify it? We check it against other clocks. If the other clocks say it is 3 o'clock and Lenny says it is 3: It is theoretically possible that all the other clocks are wrong and have exactly the same error, but it would take a whole lot of explaining as to how that could be the case.
Con's problem is that all the reasonable scientific comparisons verify that radiometric dating has the accuracy claimed. All Con has done is cite a few limitations on some of the specific methods. It's true that argon dating cannot be used on samples exposed to air. It's true that carbon dating doesn't work on coal that is loaded with radioactive thorium.
Scientists are trained to discover such problems and to avoid them. There are analogous problems with applying virtually any measurement technique. We can list pitfalls with using clocks or micrometers or scales or anything else that measures. That is not at issue. The question is what accuracy is achieved despite all the potential problems.
Report this Argument Con Again, I would like to think Pro for the opportunity to debate this and for his alacritous response. First, I would like to point out some errors my opponent made in his last response. He stated, "Con is correct that rock samples selected for argon dating cannot have been exposed to air.
I said there was "excess argon. However, the samples still came back with unacceptable ages. Therefore, the excess argon must have come from some other source. The mantle has been suggested. So there is risk of contamination not just from air, but from some other source. Pro also posited that "The error due to air exposure always makes the sample appear younger than it really is.
A less than 10 year old sample should have no measurable Ar. Pro also resorted to special pleading when he said I sourced a "religious" journal.
In fact, it was a scientific journal, but because it supports creationism he immediately rejects it as "religious" instead of trying to actually refute it based on scientific data. I can as easily say talkorigins. Pro also questions A. All Snelling is doing is using language in which that particular audience would understand.
The conventional geological community has named the different rock units in the rock record. So if Snelling is going to discuss the chalk beds in the cretaceous rock unit he will say "cretaceous" so his peers know what he is talking about. It doesn't mean he accepts the ages that geologists have imposed on it. If I am going to go on a business trip to Japan I might do well to speak Japanese. Furthermore, Pro cites my sources incorrectly.
Whitelaw was not the one who said the samples dated within 50, years. Whitelaw was quoting the journal "Radiocarbon. There are no reliable sources that back up that claim. Even the article he sourced, which was merely a email sent to talkorigins, says "it looks like in-situ production of new 14C is the best-supported hypothesis; but research is ongoing However, the answer to the detection of C in diamonds fits a young earth hypothesis just as good, if not better, than Th creating C which is lacking in evidence.
Furthermore, U and Th decay does create Helium. He is the second lightest element and diffuses out of minerals and rocks quickly. They have measured He diffusion rates from Zircons that are supposedly 1. It seems not all dating methods cross-check each other as my opponent asserts. So why do some independent dating methods appear to match? The simple answer is they don't. The conventional geological community has the presupposition that the earth is billions of years old.
So when they date a rock layer with any radiometric dating method that doesn't match the "expected" age they already had for the rock layer they throw it out and keep dating until they get the results they wanted. It has been admitted as such: If it does not entirely contradict them, we put it in a footnote, and if it is completely out of date we just drop it" T. True, this quote is frombut why should we believe scientists are any different today? The only way scientists know radiometric dating results are incorrect is because they already had preconceived ideas of the what the age of a rock was.
It is the relentless application of uniformitarianism that creates these perceived matches with independent dating methods. It is assumed that tree rings form one a year, but it is actually well known that tree rings can form several in one year depending on the climate the tree is growing in http: If we eliminate the uniformitarian philosophy we can see that it makes the assumption of tree rings difficult to prove.
Furthermore, the oldest tree, appropriately nicknamed Methuselah, is only years old according to conventional dating http: If the earth is billions of years old why are there not any older trees than a few thousand years old? Varves are conventionally believed to be laid down one a year. However, a Florida Hurricane deposited a six-inch-thick mud layer with numerous thin laminae Journal of Geology, What would a yearlong global flood do?
Coral reef growth is claimed to take long ages to have grown. The Enewetok Atoll in the Pacific Ocean is usually pointed to as an example. We also need to know that no parent or daughter has entered or left the system in the meantime. Radiometric dating is commonly used on igneous rocks lavaand on some sedimentary minerals.
But fossils can generally not be dated directly. When lava is hot, argon escapes, so it is generally assumed that no argon is present when lava cools. Thus we can date lava by K-Ar dating to determine its age. As for the other methods, some minerals when they form exclude daughter products. Zircons exclude lead, for example, so U-Pb dating can be applied to zircon to determine the time since lava cooled.
Micas exclude strontium, so Rb-Sr dating can be used on micas to determine the length of time since the mica formed. I found the following statement in an on-line non creationist reference, as follows: In rubidium-strontium dating, micas exclude strontium when they form, but accept much rubidium. In uranium-lead U-Pb dating of zircon, the zircon is found to exclude initial lead almost completely. The Interpretation and Dating of the Geologic Record.
Thus one would know that any strontium that is present had to come from the parent rubidium, so by computing the ratio and knowing the half life, one can compute the age. In general, when lava cools, various minerals crystallize out at different temperatures, and these minerals preferentially include and exclude various elements in their crystal structures.
So one obtains a series of minerals crystallizing out of the lava. Thus the composition of the lava continues to change, and later minerals can form having significantly different compositions than earlier ones. Lava that cools on the surface of the earth is called extrusive. This type of lava cools quickly, leaving little time for crystals to form, and forms basalt.
Lava that cools underground cools much more slowly, and can form large crystals. This type of lava typically forms granite or quartz.
Why methods in general are inaccurate I admit this is a very beautiful theory. This would seem to imply that the problem of radiometric dating has been solved, and that there are no anomalies.
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.
I doubt it very much. If the radiometric dating problem has been solved in this manner, then why do we need isochrons, which are claimed to be more accurate? The same question could be asked in general of minerals that are thought to yield good dates. Mica is thought to exclude Sr, so it should yield good Rb-Sr dates. But are dates from mica always accepted, and do they always agree with the age of their geologic period?
Assumptions of Radioactive Dating • Smilodon's Retreat
Indeed, there are a number of conditions on the reliability of radiometric dating. For example, for K-Ar dating, we have the following requirements: For this system to work as a clock, the following 4 criteria must be fulfilled: The decay constant and the abundance of K40 must be known accurately.
There must have been no incorporation of Ar40 into the mineral at the time of crystallization or a leak of Ar40 from the mineral following crystallization. The system must have remained closed for both K40 and Ar40 since the time of crystallization. The relationship between the data obtained and a specific event must be known. The earth is supposed to be nearly 5 billion years old, and some of these methods seem to verify ancient dates for many of earth's igneous rocks. The answer is that these methods, are far from infallible and are based on three arbitrary assumptions a constant rate of decay, an isolated system in which no parent or daughter element can be added or lost, and a known amount of the daughter element present initially.
Heating and deformation of rocks can cause these atoms to migrate, and water percolating through the rocks can transport these substances and redeposit them. These processes correspond to changing the setting of the clock hands. Not infrequently such resetting of the radiometric clocks is assumed in order to explain disagreements between different measurements of rock ages.
Some more quotes from the same source: In the lead-uranium systems both uranium and lead can migrate easily in some rocks, and lead volatilizes and escapes as a vapor at relatively low temperatures. It has been suggested that free neutrons could transform Pb first to Pb and then to Pb, thus tending to reset the clocks and throw thorium-lead and uranium-lead clocks completely off, even to the point of wiping out geological time.
Furthermore, there is still disagreement of 15 percent between the two preferred values for the U decay constant. Potassium volatilizes easily, is easily leached by water, and can migrate through the rocks under certain conditions. Furthermore, the value of the decay constant is still disputed, although the scientific community seems to be approaching agreement. Historically, the decay constants used for the various radiometric dating systems have been adjusted to obtain agreement between the results obtained.
Argon, the daughter substance, makes up about one percent of the atmosphere, which is therefore a possible source of contamination.
However, since it is possible for argon to be formed in the rocks by cosmic radiation, the correction may also be in error. Argon from the environment may be trapped in magma by pressure and rapid cooling to give very high erroneous age results. Rubidium parent atoms can be leached out of the rock by water or volatilized by heat. All of these special problems as well as others can produce contradictory and erroneous results for the various radiometric dating systems.
So we have a number of mechanisms that can introduce errors in radiometric dates. Heating can cause argon to leave a rock and make it look younger.
In general, if lava was heated after the initial flow, it can yield an age that is too young. If the minerals in the lava did not melt with the lava, one can obtain an age that is too old. Leaching can also occur; this involves water circulating in rock that can cause parent and daughter elements to enter or leave the rock and change the radiometric age. Thus it is easy to rationalize any date that is obtained. If a date is too old, one can say that the mineral did not melt with the lava.
Maybe it got included from surrounding rock as the lava flowed upward. If the date is too young, one can say that there was a later heating event. One can also hypothesize that leaching occurred.
But then it is claimed that we can detect leaching and heating. But how can we know that this claim is true, without knowing the history of rocks and knowing whether they have in fact experienced later heating or leaching? The problems are compounded because many of the parent and daughter substances are mobile, to some extent. I believe that all parent substances are water soluble, and many of the daughter products as well. A few sources have said that Sr is mobile in rock to some extent.
This could cause trouble for Rb-Sr dating. In fact, some sources say that Sr and Ar have similar mobilities in rock, and Ar is very mobile. Especially the gaseous radioactive decay byproducts such as argon, radon, and helium are mobile in rock. So if a rock has tiny cracks permitting gas to enter or escape or permitting the flow of water, the radiometric ages could be changed substantially even without the rock ever melting or mixing.
Now, there is probably not much argon in a rock to start with. So the loss of a tiny amount of argon can have significant effects over long time periods. A loss of argon would make the rock look younger. In a similar way, argon could enter the rock from the air or from surrounding rocks and make it look older. And this can also happen by water flowing through the rock through tiny cracks, dissolving parent and daughter elements.
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. I also question the assertion that argon, for example, is excluded from certain minerals when they crystallize and never enters later on. Geologists often say that ages that are too old are due to excess argon. So it must be possible for that excess argon to get in, even though the crystal is supposed to exclude it.
Here is one such reference, although this is to a mineral that does not exclude argon: In a few cases, argon ages older than that of the Earth which violate local relative age patterns have even been determined for the mineral biotite.
Such situations occur mainly where old rocks have been locally heated, which released argon into pore spaces at the same time that new minerals grew. Under favourable circumstances the isochron method may be helpful, but tests by other techniques may be required.
For example, the rubidium-strontium method would give a valid isotopic age of the biotite sample with inherited argon. For example, different kinds of quartz have different colors due to various impurities that are included but not part of the repetitive unit of the quartz crystal. So even if the crystal excludes the daughter element, it could be present in impurities.
Thus crystals, as they form, may have tiny imperfections that accept parent and daughter products in the same ratios as they occur in the lava, so one can inherit ages from the lava into minerals in this way.
It is also possible that parent and daughter elements could be present in boundaries between regular crystal domains. I don't know how we can be sure that a crystal will exclude argon or other daughter substances except by growing it in the laboratory under many conditions. There can also be argon or other daughter products added from the air or from other rocks. One could say that we can detect whether the daughter is embedded in the crystal structure or not.
But this would require an atom by atom analysis, which I do not believe is practical. Why K-Ar dating is inaccurate Since K-Ar potassium-argon dating is one of the most prevalent techniques, some special commentary about it is in order.
Potassium is about 2. Argon is about 3. This is about one ten millionth of the mass of the rock, a very tiny percentage. And yet, with a large amount of argon in the air and also filtering up from rocks below, and with excess argon in lava, with argon and potassium water soluble, and argon mobile in rock, we are still expecting this wisp of argon to tell us how old the rock is!
The percentage of Ar40 is even less for younger rocks. For example, it would be about one in million for rocks in the vicinity of 57 million years old. To get one part in 10 million of argon in a rock in a thousand years, we would only need to get one part in 10 billion entering the rock each year. This would be less than one part in a trillion entering the rock each day, on the average.
This would suffice to give a rock having an average concentration of potassium, a computed potassium-argon age of over million years! We can also consider the average abundance of argon in the crust. This implies a radiometric age of over 4 billion years. So a rock can get a very old radiometric age just by having average amounts of potassium and argon.
It seems reasonable to me that the large radiometric ages are simply a consequence of mixing, and not related to ages at all, at least not necessarily the ages of the rocks themselves. The fact that not all of the argon is retained would account for smaller amounts of argon near the surface, as I will explain below.
This could happen because of properties of the magma chambers, or because of argon being given off by some rocks and absorbed by others. I don't see how one can possibly know that there are no tiny cracks in rocks that would permit water and gas to circulate. The rates of exchange that would mess up the dates are very tiny. It seems to me to be a certainty that water and gas will enter rocks through tiny cracks and invalidate almost all radiometric ages.
Let me illustrate the circulation patterns of argon in the earth's crust. So argon is being produced throughout the earth's crust, and in the magma, all the time. In fact, it probably rises to the top of the magma, artificially increasing its concentration there.
Now, some rocks in the crust are believed not to hold their argon, so this argon will enter the spaces between the rocks. Leaching also occurs, releasing argon from rocks. Heating of rocks can also release argon. Argon is released from lava as it cools, and probably filters up into the crust from the magma below, along with helium and other radioactive decay products.
All of this argon is being produced and entering the air and water in between the rocks, and gradually filtering up to the atmosphere. But we know that rocks absorb argon, because correction factors are applied for this when using K-Ar dating. So this argon that is being produced will leave some rocks and enter others.
The partial pressure of argon should be largest deepest in the earth, and decrease towards the surface. This would result in larger K-Ar ages lower down, but lower ages nearer the surface. As for K-Ar dating, here is a quote given above: Now, argon is very soluble in magma, which can hold a lot of it: After the material was quenched, the researchers measured up to 0. They noted, 'The solubility of Ar in the minerals is surprisingly high'.
This is from a paper by Austin available at ICR. This paper also discusses Mount St. Helens K-Ar dating, and historic lava flows and their excess argon.
So magma holds tremendous amounts of argon. Now, consider an intrusive flow, which cools within the earth. All its argon will either remain inside and give an old age to the flow, or will travel through surrounding rock, where it can be absorbed by other rocks.
So magma should have at least 20 times as much argon as a rock million years old by K-Ar dating. In fact, the argon in the magma may well be even higher, as it may concentrate near the top. This amount of argon is enough to raise 20 times the volume of magma to a K-Ar age of million years, and probably times the volume of the magam to an age of 57 million years. So one sees that there is a tremendous potential for age increases in this way.
It is not necessary for this increase in age to happen all at once; many events of this nature can gradually increase the K-Ar ages of rocks. In general, older rocks should have more argon because they have been subject to more exposure to such argon, but their true age is not necessarily related to their K-Ar radiometric age.
We can also consider that most volcanoes and earthquakes occur at boundaries between plates, so if the lava has flowed before, it is likely to flow again nearby, gradually increasing the age.
I suppose earthquakes could also allow the release of argon from the magma. Other mechanisms include dissolving of rock, releasing its argon, fracturing of rock, with release of argon, argon from cooling lava under water entering the water and entering other rocks, and argon from cooling lave entering subterranean water and being transported to other rock.
There are so many mechanisms that it is hard to know what pattern to expect, and one does not need to rely on any one of them such as more argon in the magma in the past to account for problems in K-Ar dating. Since even rocks with old K-Ar dates still absorb more argon from the atmosphere in short time periods, it follows that rocks should absorb quite a bit of argon over long time periods, especially at higher pressures.
In fact, if a rock can absorb only a ten millionth part of argon, that should be enough to raise its K-Ar age to over million years, assuming an average amounts of potassium. It wouldn't require many internal cracks to allow a ten millionth part of argon to enter. Also, as the rock deforms under pressure, more cracks are likely to form and old ones are likely to close up, providing more opportunity for argon and other gases to enter.
I mentioned a number of possibilities that could cause K-Ar dates to be much older than the true ages of the rocks. Here is another way that K-Ar dates can be too old: If we assume the earth went through a catastrophe recently, then the crustal plates might have been agitated, permitting lava and argon to escape from the magma.
Thus a lot of argon would be filtering up through the crust. As intrusive flows of lava cooled inside the crust, they would have been in an environment highly enriched in argon, and thus would not have gotten rid of much of their argon.
Thus they would have hardened with a lot of argon inside. This would make them appear old. The same goes for extrusive flows on the surface, since argon would be filtering up through the earth and through the lava as it cooled. The following was sent to me by a friend: In areas where tremendous tectonic activity has taken place, highly discordant values for the ages are obtained.
The difficulties associated are numerous and listed as follows: There seems to be a great deal of question regarding the branching ratio for K40 into Ar40 and Ca But the value is not really known.
The observed value is between 0. However, this doesn't remedy the situation and the ages are still too high [low? The geochronologists credit this to "argon leakage". There is far too much Ar40 in the earth for more than a small fraction of it to have been formed by radioactive decay of K This is true even if the earth really is 4.
In the atmosphere of the earth, Ar40 constitutes This is around times the amount that would be generated by radioactive decay over the age of 4.
Certainly this is not produced by an influx from outer space. Thus, a large amount of Ar40 was present in the beginning. Since geochronologists assume that errors due to presence of initial Ar40 are small, their results are highly questionable. Argon diffuses from mineral to mineral with great ease. It leaks out of rocks very readily and can move from down deep in the earth, where the pressure is large, and accumulate in an abnormally large amount in the surface where rock samples for dating are found.
They would all have excess argon due to this movement. This makes them appear older. Rocks from deeper in the crust would show this to a lesser degree. Also, since some rocks hold the Ar40 stronger than others, some rocks will have a large apparent age, others smaller ages, though they may actually be the same age. If you were to measure Ar40 concentration as function of depth, you would no doubt find more of it near the surface than at deeper points because it migrates more easily from deep in the earth than it does from the earth into the atmosphere.
It is easy to see how the huge ages are being obtained by the KAr40 radiometric clock, since surface and near-surface samples will contain argon due to this diffusion effect. Some geochronologists believe that a possible cause of excess argon is that argon diffuses into mineral progressively with time. Significant quantities of argon may be introduced into a mineral even at pressures as low as one bar. If such [excessive] ages as mentioned above are obtained for pillow lavas, how are those from deep-sea drilling out in the Atlantic where sea-floor spreading is supposed to be occurring?
Potassium is found to be very mobile under leaching conditions. This could move the "ages" to tremendously high values. Ground-water and erosional water movements could produce this effect naturally. Rocks in areas having a complex geological history have many large discordances. In a single rock there may be mutually contaminating, potassium- bearing minerals. There is some difficulty in determining the decay constants for the KAr40 system.
Geochronologists use the branching ratio as a semi-emperical, adjustable constant which they manipulate instead of using an accurate half-life for K A number of recent lava flows within the past few hundred years yield potassium-argon ages in the hundreds of thousands of years range. This indicates that some excess argon is present. Where is it coming from? And how do we know that it could not be a much larger quantity in other cases? If more excess argon were present, then we could get much older ages.
It is true that an age difference in the hundreds of thousands of years is much too small to account for the observed K-Ar ages. But excess argon is commonly invoked by geologists to explain dates that are too old, so I'm not inventing anything new. Second, there may have been a lot more more argon in the magma in the past, and with each eruption, the amount decreased. So there would have been a lot more excess argon in the past, leading to older ages.
For rocks that are being dated, contamination with atmospheric argon is a persistent problem that is mentioned a number of times. Thus it is clear that argon enters rock easily. It is claimed that we can know if a rock has added argon by its spectrum when heated; different temperatures yield different fractions of argon.
It is claimed that the argon that enters from the atmosphere or other rocks, is less tightly bound to the crystal lattice, and will leave the rock at a lower temperature. But how do we know what happens over thousands of years? It could be that this argon which is initially loosely bound if it is so initially gradually becomes more tightly bound by random thermal vibrations, until it becomes undetectable by the spectrum technique. The fact that rock is often under high pressure might influence this process, as well.
The branching ratio problem We now consider in more detail one of the problems with potassium-argon dating, namely, the branching ratio problem. Here is some relevant information that was e-mailed to me. There are some very serious objections to using the potassium-argon decay family as a radiometric clock. The geochronologist considers the Ca40 of little practical use in radiometric dating since common calcium is such an abundant element and the radiogenic Ca40 has the same atomic mass as common calcium.
Here the actual observed branching ratio is not used, but rather a small ratio is arbitrarily chosen in an effort to match dates obtained method with U-Th-Pb dates. The branching ratio that is often used is 0. Thus we have another source of error for K-Ar dating. The Branching Ratio Dr.
Henke criticized some statements in my article taken from Slusher about the branching ratio for potassium.
Slusher asserted that the best known value of the branching ratio was not always used in computing K-Ar radiometric ages. Unfortunately, Dalrymple says nothing about the calculation of the branching ratio. He simply gives the correct value for the K-Ar system. The issue is not just how well this was known in the past, but which value was actually used, and whether dates published in the past have been computed with the most recent value.
Often values for constants are standardized, so that the values actually used may not be the most accurate known. All that Dalrymple says is that his ages were all recomputed using the most accurate values of the constants. This implies that some of them were originally computed using less accurate values, which is similar to Slusher's point.
He admits that Slusher's statements about it would have been true in the 's and early 's, but are no longer true. But he didn't say when the correct value for the branching ratio began to be used. Even some figures from Faure, Principles of Isotope Geology, are based on another constant that is 2 or 3 percent too low, according to Dalrymple, and so there may be many ages in the literature that need revision by small amounts.
However, Harland et al imply that nearly the correct value for the branching ratio has been known and used since the mid-fifties. We now consider whether they can explain the observed dates.
In general, the dates that are obtained by radiometric methods are in the hundreds of millions of years range. One can understand this by the fact that the clock did not get reset if one accepts the fact that the magma "looks" old, for whatever reason. That is, we can get both parent and daughter elements from the magma inherited into minerals that crystallize out of lava, making these minerals look old. Since the magma has old radiometric dates, depending on how much the clock gets reset, the crust can end up with a variety of younger dates just by partially inheriting the dates of the magma.
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. And Harold Coffin's book Creation by Design lists a study showing that Rb-Sr dates are often inherited from the magma. Even the initial ratios of parent and daughter elements in the earth do not necessarily indicate an age as old as 4.
Radioactive decay would be faster in the bodies of stars, which is where scientists assume the heavy elements formed. Imagine a uranium nucleus forming by the fusion of smaller nucleii. At the moment of formation, as two nucleii collide, the uranium nucleus will be somewhat unstable, and thus very likely to decay into its daughter element.
The same applies to all nucleii, implying that one could get the appearance of age quickly. Of course, the thermonuclear reactions in the star would also speed up radioactive decay.
But isochrons might be able to account for pre-existing daughter elements. Furthermore, some elements in the earth are too abundant to be explained by radioactive decay in 4. Some are too scarce such as helium. So it's not clear to me how one can be sure of the 4.
Why older dates would be found lower in the geologic column especially for K-Ar dating In general, potassium-argon dates appear to be older the deeper one goes in the crust of the earth. We now consider possible explanations for this. There are at least a couple of mechanisms to account for this. In volcano eruptions, a considerable amount of gas is released with the lava. This gas undoubtedly contains a significant amount of argon Volcanos typically have magma chambers under them, from which the eruptions occur.
It seems reasonable that gas would collect at the top of these chambers, causing artificially high K-Ar radiometric ages there.
In addition, with each successive eruption, some gas would escape, reducing the pressure of the gas and reducing the apparent K-Ar radiometric age. Thus the decreasing K-Ar ages would represent the passage of time, but not necessarily related to their absolute radiometric ages.
As a result, lava found in deeper layers, having erupted earlier, would generally appear much older and lava found in higher layers, having erupted later, would appear much younger. This could account for the observed distribution of potassium-argon dates, even if the great sedimantary layers were laid down very recently. In addition, lava emerging later will tend to be hotter, coming from deeper in the earth and through channels that have already been warmed up.
This lava will take longer to cool down, giving more opportunity for enclosed argon to escape and leading to younger radiometric ages. Another factor is that rocks absorb argon from the air. It is true that this can be accounted for by the fact that argon in the air has Ar36 and Ar40, whereas only Ar40 is produced by K-Ar decay.
But for rocks deep in the earth, the mixture of argon in their environment is probably much higher in Ar40, since only Ar40 is produced by radioactive decay. As these rocks absorb argon, their radiometric ages would increase.
This would probably have a larger effect lower down, where the pressure of argon would be higher. Or it could be that such a distribution of argon pressures in the rocks occurred at some time in the past. This would also make deeper rocks tend to have older radiometric ages. Recent lava flows often yield K-Ar ages of aboutyears.
This shows that they contain some excess argon, and not all of it is escaping. If they contained a hundred times more excess argon, their K-Ar ages would be a hundred times greater, I suppose. And faster cooling could increase the ages by further large factors. I also read of a case where a rock was K-Ar dated at 50 million years, and still susceptible to absorbing argon from the air.
This shows that one might get radiometric ages of at least 50 million years in this way by absorbing Ar40 deep in the earth without much Ar36 or Ar38 present. If the pressure of Ar40 were greater, one could obtain even greater ages. Yet another mechanism that can lead to decreasing K-Ar ages with time is the following, in a flood model: One can assume that at the beginning of the flood, many volcanoes erupted and the waters became enriched in Ar Then any lava under water would appear older because its enclosed Ar40 would have more trouble escaping.
As time passed, this Ar40 would gradually pass into the atmosphere, reducing this effect and making rocks appear younger. In addition, this would cause a gradient of Ar40 concentrations in the air, with higher concentrations near the ground. This also could make flows on the land appear older than they are, since their Ar40 would also have a harder time escaping. Cross-examination The Mobility of Argon Dr. Henke criticizes my concern that argon can move in and out of minerals: Plaisted wants to give his readers the impression that argon can readily move in and out of minerals and, therefore, the gas is too volatile for radiometric dating.
Specifically, he quotes one of his anonymous friends that claims that argon easily diffuses from minerals p. Of course, these statements are inaccurate generalizations. Geochronologists are aware that excess argon may accumulate on mineral surfaces and the surface argon would be removed before analysis.
However, Henke admits that this can happen in some cases. He states that geologists are aware of this problem, and make allowances for it.
But it is more difficult to remove argon that has deposited on cracks in the mineral, which can be difficult to see. Henke referenced Davis A. Young frequently, but I was not able to find Young referenced in any of the other sources I examined except Dalrymple Henke states that hornblendes retain argon very well, but then later says that they can easily absorb excess argon. Geologists also recognize that heating causes argon to leave minerals, and that dissolved argon in a mineral that does not escape will become incorporated into it, artificially increasing its K-Ar age.
I will comment more on this below, but a few comments now are appropriate. For a temperature of K 27 degrees Cthere is no significant argon loss from biotite. At K degrees Cthere is a slow but significant diffusion rate. At K degrees Closs of argon is quite rapid. To lose one percent in one year requires a temperature of nearly degrees centigrade. Thus the temperature does not have to be very high for argon to move through rock.
This also justifies Slusher's statements about argon moving in and out of rocks with ease. However, it does not seem likely that sedimentary rocks would be this hot very often, except near lava or magma flows.
Our reliance on fossil fuel combustion is ruining carbon dating
But argon does not need to move through all rock in order to influence radiometric dates, it only has to reach ancient lava flows. This it can do by following the path of the ancient lava flow itself, coming up along the path of the magma. As the magma or lava cools, this path will consist entirely of hot magma or lava, and so the argon will have a free path, and will continue to enter the magma as it cools.
Thus in many cases, the lava or magma will never completely degas, and extra argon will end up trapped in the cooled rock. This will result in artificially increased K-Ar ages. Many ancient lava flows are relatively flat, in contrast to modern ones. Also, they appear to have been covered over quickly. The flatness means that the lava is a contiguous mass, and can still be reached from the hot magma by a continuous path of hot rock.