Creationists Blind Dates
Radiometric dating breakthroughs by Carl Wieland A few years ago, some Ed., Fifth International Conference on Creationism, Creation Science Fellowship. Using radioactive dating, scientists have determined that the Earth is the days of creation (Genesis 1) were literal days and that the earth is. Radiometric dating involves dating rocks or other objects by . Ultimately these " creation scientists" were forced to admit that even for methods.
More details can be found in Eicherchapter 6; and Faul From what I have said it might seem that the assignment of ages to rocks is still a bit uncertain. However, I hope that it will help to quell anxieties when I point out that a large number of independent methods have been applied to a vast array of different rocks.
The result of this enormous array of tests is a consensus. The ages assigned to various rock strata bearing distinctive types of fossils show extraordinary agreement.
Teaching about Radiometric Dating
The many independent computations of the age of the earth during the last three decades almost invariably yield a figure between 4. Of course, there are occasional puzzling discrepancies. But geologists take these as signs that unanticipated factors have affected the system from which the result was obtained. They know that geological clocks, like other clocks, can go wrong.
Frequently, further investigation dissolves the anomaly by showing what the interfering factor has been. Let us now take up some of the Creationists' attempts to criticize radiometric dating. The main lines of attack are laid down by Morris. He begins by identifying three assumptions of the use of radiometric techniques: The system must have been a closed system.
The process rate must always have been the same" Morris a, We have already discussed statements akin to Morris's first and second assumptions. As will become clear shortly, the status of the third is a little different.
Unsurprisingly, Morris believes that he can provide good reasons for doubting each of these assumptions in the case of every application of every method. He claims that none of the assumptions is "provable, testable, or even reasonable" Morris a, Here are the reasons: There is no such thing in nature as a closed system. The concept of a closed system is an ideal concept, convenient for analysis but non-existent in the real world. The idea of a system remaining closed for millions of years becomes an absurdity.
It is impossible to ever know the initial components of a system formed in prehistoric times. Obviously no one was present when such a system was first formed. Since creation is at least a viable possibility, it is clearly possible that some of the "daughter" component may have been initially created along with the "parent" component.
Even apart from this possibility, there are numerous other ways by which daughter products could be incorporated into the systems when first formed. No process rate is unchangeable. Every process in nature operates at a rate which is influenced by a number of different factors. If any of these factors change, the process rate changes. Rates are at best only statistical averages, not deterministic constants.
Morris a, These rejoinders make it apparent that Morris's formulations of the assumptions underlying radiometric dating are only akin to the assumptions examined above. When geologists calculate the ages of rocks, they do assume that the system under consideration has remained closed in one particular respect.
They suppose that none of the daughter element has been added or subtracted. However, this does not commit them to the idea that the system was completely closed, that it engaged in no exchange of matter or energy with the environment.
Radiometric Dating and Creation Science
Like his memorable argument about the evolving junkyard, Morris's first reply only demonstrates his lack of understanding of basic concepts of physics. The crucial question is whether we can ever be justified in believing that the system was never contaminated by extra amounts of the daughter element. I have tried to explain how geologists can sometimes obtain good evidence for this conclusion.
Similarly, the second point is misguided. Geologists do not have to suppose that the system originally contained none of the daughter element. What is important is that they be able to compute the amount of the daughter element originally present. Clearly, it is required only that D0 be known, not that it be zero. It is perfectly possible to have excellent evidence for statements about events and situations that no human has observed. Geologists draw conclusions about the composition of original rocks by applying claims about the possibilities of incorporating elements into minerals, claims that can be tested in the laboratory.
So, for example, the thesis that certain minerals would have contained no original argon rests on a perfectly testable and well-confirmed claim. While those minerals were in the molten state, prior to the solidification of the rock, argon would have diffused from them. It is only after the molten rock has solidified that the argon formed through radioactive decay becomes trapped within it.
Obviously, what is being applied in this case is our knowledge of the physical and chemical interactions of minerals and elements. Morris's third assumption, and his attempt to undermine it, raises a new issue. In deriving equation 4from which rock ages can be computed, I employed equation 1the equation of radioactive decay. I asserted that l, which measures the rate of decay, is a constant.
Morris suggests that the assertion is unwarranted. However, the claim that l is a constant does not descend out of thin air.
It is the result of our knowledge of nuclear physics. Although the sciences sometimes teach us that the rate at which a process occurs can be affected by a number of factors, as when we learn that the rate at which water boils is affected by the pressure or that the rate at which mutations occur varies with X-ray irradiation, what we sometimes discover is that a process is impervious to outside influence. Precious little affects the time of passage for a light ray between two points.
Similarly, nuclear physics tells us that radioactive decay is well insulated against external interference. The reason is that the emission of particles from an atomic nucleus is under the control of forces that are enormously more effective at short distances than the forces at work in most physicochemical reactions.
Extensive attempts to modify these rates under a variety of physicochemical conditions have produced no effects. For example, his chief weapon in arguing for the possibility of variable decay rates is a vague proposal that the capture of free neutrons or the impact of neutrinos could affect decay constants Morris a, The latter idea is linked to a paragraph quoted from a "Scientific Speculation" column.
But neither of these processes would affect rates of decay; even granting the possibility of change by neutrino impact or the practical likelihood of neutron capture, the result of these processes would be a modification not of the decay rate, but of the decaying nucleus. The old nucleus, which had been decaying at its specific rate, would be changed to a new nucleus, which would then change at its specific rate.
Note that if processes like these were to occur, they would be detectable since two separate sets of daughter elements would be produced. Morris's speculations are based on confusion.
Morris then goes on to ignore the methods that geologists employ to ascertain the original amount of daughter element present in the rocks they attempt to date. His discussion of uranium-lead dating contains no mention of the simple technique for computing the initial abundance of lead that I described above.
- Radiometric dating
Needless to say, nothing is said about more sophisticated methods. His treatment of potassium argon dating includes the statement: However, argon is an inert gas, which does not become chemically bound to potassium minerals.
Moreover, the crystalline structure of some minerals makes them impermeable to argon. Hence the suggestion that the minerals that geologists date are easily contaminated is simply false. My brief discussion has only looked at a sample of the objections that Morris and his colleagues notably Slusher; see Slusher offer against radiometric dating. The errors I have identified are typical.
No attempt is made to criticize the techniques that geologists carefully employ to determine the value of D0 or to test whether the system has been contaminated. Instead, those techniques are ignored.
The picture thus presented is that radiometric dating methods compute the ages of rocks by applying equation 4assuming dogmatically that D0 is zero and that the system is uncontaminated.
Add to this distortion some vague speculations about changing decay rates perhaps based on a revisionist nuclear physics under development at the Institute for Creation Research? I shall deal with the positive arguments for a young earth in much less detail.
Other elements used for dating, such as rubidium, occur in some minerals but not others, restricting usefulness. Carbon decays almost completely withinyears of the organism dying, and many fossils and rock strata are hundreds of times older than that.
To date older fossils, other methods are used, such as potassium-argon or argon-argon dating. Other forms of dating based on reactive minerals like rubidium or potassium can date older finds including fossils, but have the limitation that it is easy for ions to move into rocks post-formation so that care must be taken to consider geology and other factors.
Radiometric dating and YEC[ edit ] See the main article on this topic: Young Earth creationism Radiometric dating — through processes similar to those outlined in the example problem above — frequently reveals that rocks, fossilsetc.
The oldest rock so far dated is a zircon crystal that formed 4. They tie themselves in logical knots trying to reconcile the results of radiometric dating with the unwavering belief that the Earth was created ex nihilo about 6, to 10, years ago. Creationists often blame contamination Indeed, special creationists have for many years held that where science and their religion conflict, it is a matter of science having to catch up with scripture, not the other way around.
This is frequently because the selected technique is used outside of its appropriate range, for example on very recent lavas.Once Upon a Time: Understanding the Mythology Behind Radioactive Dating
In attempting to date Mt. Helens, creationists attempted discredit the discipline through dishonest practices. Ultimately these "creation scientists" were forced to admit that even for methods they accepted as sound, the age of the Earth would be vastly greater than the 6, they set out to prove. Is radioactive decay constant?