Reprinted by permission of Associates for Biblical Research (ABR). All rights reserved. The web site of ABR is

Radioactive atoms are capable of spontaneously changing, or decaying, to atoms of a different type. A parent radioactive atom decays into a daughter atom in various ways, one of which is by the emission of an alpha (a) particle. Numerous types of radioactive atoms occur in nature, but only three are the initiators of a decay chain. For this book the one beginning with uranium-238 (238U In scientific notation) is most important.

The numerical superscript denotes the number of protons and neutrons in the nucleus and signifies how heavy the element is. Isotopes of the same element have different masses but nearly identical chemical behavior–as for example (238U and 235U). An alpha (a) particle has a mass of 4.

Uranium-238 initiates a chain of steps which ends with the element lead (chemical symbol Pb). The 238U decay chain, as shown below, has some daughters which decay by emitting a beta (b) particle, which is nearly 2000 times lighter than the more massive alpha a) particle.

238U -> 234Th -> 234Pa -> 234U-> 230Th -> 226Ra ->222Rn -> 218Po -> 214Pb -> 214Bi -> 214Po ->210Pb -> 210Bi -> 210Po -> 206Pb (stable end product)

U-uranium Rn-radon
Th-thorium Po-polonium
Pa-protactinium Bi-bismuth
Ra-radium Pb-lead

The half-life of a radioactive isotope is the time required for half the atoms in any collection to decay. If 1000 atoms exist at a certain time, then only 500 will remain after one half-life, after two half-lives only 250 atoms of the original collection will remain, and so forth. Half-life and decay rate are closely related quantities. Isotopes that decay quickly have short half-lives; those that decay more slowly have longer half-lives. At present 238U is decaying very slowly with a half-life of 4.5 billion years.


Figure 1.2 Sunburst Effect of Alpha-Damage Trails

Sunburst pattern of alpha-damage trails produces a spherically colored shell around the halo center. Each arrow represents 5 million alpha particles emitted from the center. Halo coloration Initially develops after 100 million alpha decays, becomes darker after 500 million, and very dark after 1 billion.

Is There Evidence for a Young Earth?

By Bob Goette, Ph.D.

There is evidence for a young earth. In the summer 1988 issue of Archaeology and Biblical Research (ABR), some evidences were touched upon in this column. This time we cite two interesting items of data from research Dr. Robert Gentry was involved in for the purpose of locating suitable sites for nuclear waste storage. A byproduct of his work was data that supports a recent creation.


Radiogenic Lead Indicates Youth

He was studying core sections taken at five different depths from about 3,000 to 15,000 feet during a drilling operation in granite. He found that the temperature increased with depth–up to 313° C (595° F) at the deepest point. It should be remembered that zircon (ZrSiO4) in these deep core wells contains small amounts of uranium and thorium (bound in lattice sites of the zircon crystal), and that the end product of this radiometric decay series is radiogenic lead (called “radiogenic’ since it is produced by the radioactive decay process).

Dr. Gentry says, “If the granites in New Mexico are over a billion and a half years old, as uniformitarian geology supposes, this would be time for considerable amounts of lead to be lost from the zircons taken from the deepest (highest temperature) sections of the drill hole. In fact, in this scenario the lead should steadily diminish with increasing depth (due to steadily increasing temperatures). However, if the earth is only several thousand years old, only negligible lead loss is expected. In this case the amount of radiogenic lead in the zircons should be about the same regardless of depth.

Here was a clear-cut test. The results of our investigations were definitive … We found that the radioactive zircon crystals extracted from the granite cores had lost essentially none of their radiogenic lead, even at the bottom of the hole where the temperatures were highest.

This is exceptionally strong evidence that the presumed 1.5 billion-year age of these granites is drastically in error. Specifically, the data are consistent with a several thousand-year age of the earth. (Gentry, Robert V., Creation’s Tiny Mystery, Earth Science Associates, Knoxville, TN, p. 164, 1986, available at


Helium Absence Indicates Youth

Other experiments with these deep core well sections were run. This time, the amount of helium was measured. During the radiometric decay of uranium to lead, alpha particles are given off. These particles are helium nuclei. Helium, a gas, has been found to migrate out of various minerals, such as zircon, even at room temperature. Hence scientists have generally given up trying to use this system as an accurate radiometric age measurement, even on surface rocks.

If the evolutionary suppositions were correct, it would be expected that because of the long earth history and the high temperatures of the deep core wells, that there would be very little or no helium left here. However, if the creation of the earth were recent (several thousand years ago), then measurable quantities of helium would be expected.

Gentry’s data indicated amazingly high retention of helium even at 197° C (387° F).

These results add to many others which indicate a relatively recent creation of the earth.

In response to Dr. Goette’s article Dr. Gregg Wilkerson sent critical comments to ABR about Robert Gentry’s work mentioned in the article. Wilkerson was then invited to update his comments prior to Gentry’s response. In what follows, Gentry responds to each of Wilkerson’s letters separately and in chronological order.

Wilkerson’s letter of February 5, 1989

Bob Goette’s article, ‘Is there evidence for a young earth?’ detracts from the otherwise excellent archaeological articles in A&BR. I have shown, along with the work of other scientists how Gentry’s conclusions are geologically impossible. I respect Gentry’s interpretation, but I think neither the public, ABR readership, or the cause of Christ is served by publicizing his theories without critical review.

Goette failed to make the basic scientific distinctions between fact, assumption, and interpretation. Gentry ASSUMES what certain lead/helium ratios ought to be, and then builds a young-earth interpretation around this assumption. His assumptions are inaccurate. The migration of lead, helium or any other element through rocks is a function of several variables. Present Isotopic ratios do not always NECESSARILY indicate past ratios, and some can be the result of present equilibrium conditions. Specifically, the assumption that some radiogenic lead and helium should have been lost at the bottom of the cores (where temperatures are highest) is NOT a correct assumption. Rocks can retain isotopic ratios, even if they are MELTED and recrystallized.

Gentry’s response to the first letter

I am pleased that Wilkerson has decided to publish his criticisms where I can respond to them. I first address the implication that my work has been publicized without critical review.

Critical Review: The experimental results Bob Goette used for his article had been peer-reviewed and published in well-known scientific journals, Science (Gentry et al., 1982a) and Geophysical Research Letters (Gentry et al., 1982b). Indeed, all my results have received the severest type of adversarial review from competent evolutionists during the process of being published in other journals such as Nature, Earth and Planetary Science Letters, Annual Reviews of Nuclear Science, and Physical Review Letters. This exposure has provided scientists everywhere with the opportunity of responding in these same journals if they felt that errors existed in my work.

Seeing that Wilkerson and his associates have criticisms, why haven’t they published them in these journals? Others have done this on two occasions (Moazed et al., 1973; Fremlin. 1975), and in both cases I showed their criticisms were spurious. (Gentry, 1974, 1975). Recently another criticism appeared (Odom and Rink, 1989) which is seriously in error, and on two occasions I have attempted to get a rebuttal published in Science. The editor rejected them both. His action speaks volumes and will probably hasten the day when all this will come to public attention.

Young earth, assumptions, and isotopic ratios: In the foregoing letter it is claimed that I build the case for a young earth on incorrect assumptions about certain isotopic ratios. This claim has no scientific basis. What I actually did, as the following discussion shows, was to design and carry out a series of experiments that would decisively test whether the earth was billions of years old, as claimed by evolutionists, or just several thousand years old, as indicated by biblical chronology.

The scientific evidence for a young earth consists of finding abnormally large amounts of uranium-derived lead and helium in tiny zircons extracted from a series of granite cores that extended to great depths where the temperature is quite high (313° C at the bottom of the drill hole). By conventional radiometric dating both the granite and the enclosed zircons are supposed to be about 1.5 billion years old. On that basis, the amount of lead, and especially helium, should exhibit a rapid decrease as a function of temperature increasing with depth, which greatly enhances diffusion of both elements out of the zircons.

What the experiments showed, however, was that the lead content of the zircons was uniform from the top to the bottom of the drill hole (Gentry et al., 1982a), and also that helium was present in significant amounts down to a depth where the temperature was 197° C (Gentry et al., 1982b). Based on the assumed ancient age of the granite, these results are contrary to the expectation that there should have been drastic reductions in the contents of these elements due to diffusion effects. The fact that both lead and helium have been highly retained is exceptionally strong evidence for only a relatively short existence of the granite (Gentry, 1984). This disproves the evolutionary view requiring billions of years for the slowly cooling formation of our planet, but it is consistent with and supportive of the biblical creation of Earth several thousand years ago (Gentry, 1984,1988). Thus the claim that the evidence for a young earth is just the result of incorrect assumptions is not only false, but it ignores the scientific evidence to the contrary.

In this context, I should also mention that the above results have nothing to do with melting of rocks, as Wilkerson’s letter implies. The temperatures in the drill hole are too low to melt of any of granite’s minerals, especially zircon, for it is an exceedingly refractory mineral that does not begin to melt until the temperature exceeds 1500 ° C.

Impossible Conclusions: Lastly, we consider the claim that Wilkerson and others have “shown” that my “conclusions are geologically impossible.” I am especially pleased that this statement has been made, for it provides the opportunity to clarify some matters that have long been confused.

To begin, in science the word “shown” refers to proof by laboratory verification. Is there really demonstrable laboratory evidence which “shows’ my ‘conclusions are geologically impossible?” Not at all. Nothing like this has ever been published. Neither Wilkerson nor any of his associates have produced any laboratory data to contradict the Po-halo evidence for creation (Gentry, 1968, 1971, 1974, 1984, 1988) or the zircon data for a young age of the earth (Gentry et al., 1982a, 1982b: Gentry, 1984, 1988), even though they and others have had the opportunity to do this for many years. Thus, they have no legitimate scientific basis for the claim that my conclusions are geologically impossible.

Then how can such a claim be understood? What has happened here is that the usual scientific meaning of “shown” has been discarded. In its stead is substituted a meaning that involves proof by assumption. And the basic assumption being used is none other than the major premise of the evolutionary framework of earth history- the uniformitarian principle- the idea that the action of known physical laws is sufficient to explain the origin and development of both the earth and all life on it. So when Wilkerson says he and others have “shown” my “conclusions are geologically impossible,” what is meant is that they utilize the standard evolutionary interpretation of earth history as the basis for that position. This is nothing new. In fact, this speculative approach has been used repeatedly since the early days of geology, namely, go into the field, examine some rocks, use uniformity as the basis for interpreting their origin and age, and then conclude their overall “history” makes creation and a young age of the earth impossible.

What is different now compared to the early days of geology, though, is the fact that I have published unrefuted scientific evidence for creation and a young age of the earth in premier scientific journals, and this evidence completely exposes the speculative basis of historical geology.

Wilkerson’s letter of March 26, 1990

Concerning Gentry’s results about creation, he and I are working to complete a 3-year effort to produce a comprehensive examination of the data relative to Po radiohalos. This discussion/reply will be published by Origins Research as a special volume for the 2nd International Conference on Creationism. At the conference, I and Richard Wakefield will be giving a paper about the “Geologic Setting of Po Radiohalos.”

Until Wakefield first published information about the geology of Po halo sites of Canada in 1986, many persons (including myself) accepted Gentry’s ‘Creation Model.’ Now we know that Po halos are found only in rocks that have experienced U/Th mineralization. In fact, many of Po halo localities are uranium mines. Often the mineral deposits (which may be veins or pegmatites) cut across fossiliferous strata. Clearly the mineral deposits and Po-halos in them are younger than the surrounding post-creation host rocks. Po haloes are reported from rocks of PreCambrian to Tertiary age. Further, they do not occur uniformly throughout the mineral deposits. They are concentrated at the intersection of fractures and cleavage planes. Selenium and uranium are known to exist in Po halo central inclusions. These facts suggest that Po halos form from migration and accumulation of Po precursors (notably Radon-222).

In regards to the matter of helium retention, the core in question was obtained from lands included in my area of responsibility as a mineral examiner for the U.S. Bureau of Land Management. The coring was done to under-stand why a silicic magma forms obsidian in one place and rhyolite in another. Diagrams of the drilling project are provided by Eichelberger et al. (1985, 1986).

Gentry’s work compared helium retention with depth, but ignored both the geometry of the core holes and the rock types through which the core drill passed. The rhyolite, volcanic breccia, glass and granite penetrated by the drill was fractured and the hole had to be cased from the surface to the bottom of the holes. Different rock types have different abilities to retain helium. Fracturing increases helium migration in all rock types. Hence, helium retention in these rocks cannot give accurate estimates about the rock’s age. The Inyo Domes are only 600 years old. They are underlain by Pliocene volcanic rocks only 3 million years old. To estimate the age of the earth based on helium retention in these rocks has very little basis.

References cited:

Eichelberger, J. L.; Lysne, P. C.; Miller, C.D.; and Younker, L. W. “Research Drilling at Inyo Domes, California: 1984 Results,” Eos Vol. 66:17 (1985), pp. 186-7.

Eichelberger, J. L.; Carrigan, C. R.; Westrich, H. R.; and Price, R.H. “Non-Explosive Silicic Volcanism,” Nature Vol. 232, pp. 598-602.

Gentry’s response to the second letter

Wilkerson and the Second International Conference on Creationism: In late spring 1990, I did receive the Program for the Second ICC, and it did confirm that Wilkerson and his associate have been scheduled to present a paper about my work at this Conference. As of near mid-June, neither Wilkerson nor his associate have sent me a copy of their paper. Neither has the ICC invited me to present a rebuttal to their criticisms at the Conference. ICC Technical Review Committee Chairman Robert Walsh, who in 1986 arranged for me speak three times at the first ICC, did send me a letter dated December 20, 1989, saying ‘Regrettably, the deadline for submission [of papers for the Second Conference] was in January 1989…” except in certain special instances. His letter mentions nothing of the planned presentation by Wilkerson and his associate. He also said that the Second ICC was “shaping up to be the greatest and most technical of any creation conference ever held.”

The Discussion/Reply Project: I have spent many months investigating the various criticisms made by Wilkerson and his associates, and I am anxious to publish my response as soon as my investigations are complete. However, it is not clear as yet (June 1990) that my work will result in a joint publication with Origins Research Copyright and other considerations may be such that I will publish separately.

My involvement in this project was predicated on the assumption that the opposing views of Earth history were to be treated on an equal basis and that I was engaged in a discussion whereby the issues were capable of being decided on a scientific basis. As is well-known, any view or theory that Is truly scientific is one whose major premises, or predictions based on those premises, can be tested in the here and now. To emphasize this point, on April 27, 1990, I wrote to Dennis Wagner, editor of Origins Research outlining several requisites for joint publication, one of which is repeated below:

A most important facet of any scientific theory is the existence of an experimental test, or tests, of the theory. In my part of the dialogue I have described granite synthesis and reproduction of Po-218 halos in granite (mica), as tests of my hypothesis that both granite and the enclosed Po halos were created in such a way that they cannot be duplicated. Gregg [Wilkerson] has had opportunity to respond at length concerning both of these tests. At the same time, however, Gregg has not stated any experimental test that could potentially falsify his model (theory) of earth history. And we need to be clear on the fact that Gregg has used a model of earth history in stating his objections to my results. Thus, in order for this dialogue to be fair, in his second series of objections Gregg needs to state exactly what experimental test would falsify his model so that I too will have opportunity to respond to this most important topic. This will give readers of the dialogue the opportunity to judge more accurately which model of earth history is based on scientific principles and which is based on ad hoc assumptions.

From the above it can be seen that I had asked for an experiment that could be done in the here and now, one whose outcome Wilkerson would accept as either confirming or falsifying the uniformitarian model that he is using. On May 11, 1990, Wilkerson responded that he had already described the test I requested, namely, that it would take 100,000 years to synthesize a granite. Initially, it seemed his test was only a restatement of the basic assumption of evolutionary geology, an assumption which I have repeatedly challenged by hard scientific data to the contrary. And then I realized that his test was open to analysis, and that the results are important enough to be made available now, especially since I am excluded from presenting them at the Second ICC Conference.

Such analysis begins with a literature search for information on the time periods that geologists calculate for the cooling and crystallization of various sizes of granitic melts. One reference that immediately comes to mind concerning a presumed 100,000-year period of granite formation is the paper given by Kurt Wise during the First ICC (Wise, 1986). I cite Wise’s results first because as one of Wilkerson’s close associates in the discussion/reply project concerning my work, we can be certain that Wilkerson has confidence in Wise’s scientific expertise. Wise calculates that much more than 100,000 years are required for cooling of a melt 10 km in diameter, and about 10,000 years for the cooling of a melt about 2 km in diameter. We observe the cooling times are becoming much less as the size of the melt is diminished.

This is exactly what we expect, and it is a most important aspect of Wilkerson’s test, for I have repeatedly challenged uniformitarian geologists to prove they have the truth about granite formation and earth history by synthesizing only a mere hand-sized specimen, not a 2 to 10-km wide mountain of granite. Success in synthesizing a hand-sized granite rock would mean they have the truth. Failure to make granite means that for well over a century they have been badly mistaken in their views of earth history. Which is it?

What does Wise say about cooling times for smaller masses? Although he does not mention the exact size, he does conclude that cooling a melt over the presumed temperature range of 200 degrees Centigrade is such that “only a month and a half of cooling is required to produce a granite” (Wise, 1986, p. 198). What is most significant about Wise’s statement about rapid formation of granite is that it provides a sufficient basis for Wilkerson’s views to be tested in the present time. It means inescapably that, according to Wilkerson’s own views, time is not a hindrance to the synthesis of granite. A month-and-a-half-long experiment is almost routine in many fields of science. But has Wise correctly stated the cooling times for small masses of granite according to conventional, uniformitarian principles? If anything, it appears his times are slightly in excess of those calculated by others.

For example, several decades ago Larsen carried out a much more detailed study of crystallization times corresponding to various sizes of melts (Larsen, 1945). Using the Southern California batholith as an example, he assumed a melt that was cooling differentially from the edge inward toward the center, and then calculated the following time periods presumed to be required for granite to crystallize at the center after various sizes of melts had “intruded” a given location: 700,000 years for a 10-km-wide melt, 7,000 years for a 1-km-wide melt, 70 years for a 100 m wide melt, and only a few days for a pool of magma 1 m wide. Thus we see that the logical conclusion of Wilkerson’s views of granite synthesis is that granite should form in only a few days. Has such ever been observed to happen?

The prediction of granite synthesis in a few days is most interesting in that it fits precisely with the claim that granite can be synthesized within one week, a claim made publicly by a University of Tennessee geology professor during my April 13, 1987. evening presentation at the University of Tennessee in Knoxville. This encounter, recorded videotape, is also described in detail in the second edition of my book, Creation’s Tiny Mystery. Copies are available from Earth Science Associates, Knoxville, TN or at

Over three years have passed, and no synthesized granite has been forthcoming from this professor or anyone else. This is not surprising because, as I related at my University of Tennessee presentation, experiments demonstrate that the rock that forms from slow cooling of a granitic melt in the laboratory is quite similar to rhyolite, the fine-grained rock that forms from a slowly cooling granitic melt deep underground in the earth. In neither the laboratory nor the earth does a slowly cooling granitic melt form granite. Thus, Wilkerson’s uniformitarian views of granite synthesis have been falsified experimentally.

Indeed, the above facts reveal that the entire basis of uniformitarian geology is false. And there really is no escape from this conclusion if one is confined to scientific issues. All this and much more is described in my part of the discussion/reply project.

Creation Model: Acceptance, Rejection, and Geological Knowledge: The essential feature of my Creation Model remains the same as when I first published it in 1979 (Gentry, 1979): God calling the earth into existence out of nothing about 6,000 years ago. Wilkerson says he accepted my Creation Model until 1986 when he learned of his associate’s geological findings, which were being circulated in the form of unpublished manuscripts. There seems little question that his associate, who is an amateur geologist, has greatly influenced Wilkerson. But there is also substantial evidence that Wilkerson left his commitment to a recently created earth several years prior to 1986.

Apparently he has forgotten the content of his own thesis, written in partial fulfillment of the requirements for his Doctor of Geological Sciences degree at the University of Texas at El Paso, and approved in December 1983. It contains some rather clear statements concerning the age of some of the rocks he studied in the Batopilas mining district in Mexico. For example, on page 267 he lists seven radiometric ages ranging from 23 million years to 85 million years on different rocks that he studied. On page 269, he discusses which of the radiometric techniques is most accurate, and concludes that in K/Ar dating the hornblende dates are the most reliable. Also on page 269 he concludes that the true age of the Las Tahonas Granodiorite is slightly older than 45.3 million years (Wilkerson. 1983). The discussion of these radiometric ages is not surprising considering that his thesis is written from the perspective of uniformitarian geology.

It was a surprise, however, when I finally learned that Wilkerson had accepted an ancient earth and a uniformitarian view of earth history long before I entered into the discussion/reply project in December 1987. For some reason this information was not given to me prior to my involvement in this project.

Regardless of why Wilkerson earlier discarded a belief in a recently created earth, what is clear is that he now uses the findings of his associate to reject my published evidence for creation. The way in which this is done is reminiscent of the speculative procedures that uniformitarian geologists have used for over a century in their attempts to discredit the Genesis record. Instead of responding to the published experimental evidence in my reports with any tangible scientific evidence, the procedure used is to raise questions, or make declarative statements that have no basis in fact, as if they were fact. In this particular instance what has been done is to enumerate many objections to my work using terminology that makes it appear that some substantial objections actually exist. In reality, what has happened is that some basic information about my results has been parasitized and then made to say the opposite of what the evidence actually reveals. In my book I have already responded to the objections given by Wilkerson in his second letter, but will briefly do so again here so as not to leave this issue in doubt.

Response to comments on Po halos: Wilkerson and his associate claim to have facts suggesting that Po halos [in rocks] formed secondarily from Radon-222. If this were true, then it follows that they and others should long ago have demonstrated that Po halos In rocks could form from this process. Have they done this? Not at all.

Instead, they claim to “know” many things concerning how Po halos in rocks are related to:

U/Th mineralization, when I have published evidence contradicting this (Gentry, 1968, 1974),

Uranium mines, when I have documented the existence of Po halos in the Conway granites, far removed from any uranium mine, fossiliferous strata, an inference which I pointed out is a red herring (Gentry, 1988; p. 326),

rocks which are younger than the surrounding post-creation rocks- which, aside from being a clear admission that we are dealing with creation not evolution, is an interpretation based on geological inference (Gentry, 1988; pp. 325-27),

fractures–when I have published clear photographs of Po halos in the minerals mica and fluorite showing this is untrue (Gentry, 1988; pp. 210-12, 215-16), and cleavage planes–when, as a geologist, Wilkerson should realize, is meaningless because every point in a mica crystal is contained along some cleavage plane,

uranium, when I have published scientific data to the contrary (Gentry, 1968, 1971, 1974; Gentry et al., 1974), and

selenium, when I have reported selenium occurs only rarely in primordial Po-halo centers in granites (Gentry, 1974; Gentry et al., 1974) compared to its abundance in secondary Po halos in coalified wood (Gentry et al., 1976).

A fuller discussion, which brings out the defects in the above claims in more detail, and also treats the Precambrian-Tertiary claim, is given in my book (Gentry, 1988; pp. 325-27), a copy of which was sent to Wilkerson over a year ago.

In any event, none of the above points dispute the creation implications of Po halos in granites. Rather the evidence only shines brighter, just as it did after my April 13, 1987 presentation at the University of Tennessee. Before that presentation Wilkerson’s associate wrote a letter to Dr. Frank Press, President of the National Academy of Sciences, claiming, among other things, that he had seen granite synthesized while viewing part of a geology course offered on television. This same claim was earlier made in a February 8, 1987 letter to me. I carefully checked into this claim prior to that evening’s presentation and found it was incorrect. And when the UT geology professor challenged me on the synthesis of granite, I read Wilkerson’s associate’s claim about granite synthesis, and then proceeded to describe how I had obtained firm experimental evidence that it was spurious. All this is related in detail in the second edition of my book (Gentry, 1988).

Helium retention and the earth’s age: In the last part of his second letter, Wilkerson again brings up the topic of helium retention and the age of the earth. This time he claims much more knowledge of the location and characteristics of the cores that I used for my helium retention experiments. He speaks authoritatively as he describes his jurisdiction over the area where my original core material was obtained, claiming in particular much knowledge about the conditions of the drilling project, and specifically mentioning obsidian and rhyolite that was cored. He speaks of fracturing of rocks and how this increases helium migration, and with this accumulated evidence behind his arguments, says that helium retention means nothing about age in the rocks that I studied. His final point is almost anticlimactic, yet he adds it to apparently prove conclusively that my results on helium retention have nothing to do with the age of the earth.

He says that the Inyo Domes, which are the rocks he has been discussing, and the ones which are in his jurisdiction as a geologist with the U. S. Bureau of Land Management in Bakersfield, CA, are only 600 years old, and they are underlain by Pliocene volcanic rocks which are only 3,000,000 years old. The clincher is when he asks, “How could such ever be used to estimate the age of the earth?’ It is too bad that such a logical and beautiful argument has to have such a poor ending. But such is life, even for scientists.

The 3,000,000 years is nothing but radiometric fiction, and his conclusions about fracturing at Inyo Domes does not pertain to my results.

The problem is that Wilkerson has used the wrong premise to draw his conclusions, and has made a very significant mistake. The cores I used for the helium retention experiments, the results of which were first published in Geophysical Research Letters (Gentry et al., 1982) and then discussed at great length in my book, did not come from Inyo Domes in California. The cores did not even come from California. They came from the 14,000-foot deep drill hole in granite in New Mexico. The temperatures at the bottom of this drill hole in granite reached 313 degrees centigrade, and the implications of higher temperature on helium retention in the tiny zircons were correctly described by Bob Goette in his A&BR article. Clearly, helium loss was due to temperature, not fracturing. The cores I used in my helium retention experiments had nothing at all to do with anything from Inyo Domes, and I do not know how or why Wilkerson came to that conclusion.

Conclusion: As I have noted many times in my book, Creation’s Tiny Mystery, if evolutionary theory were correct, it should be possible to reproduce both granite and polonium halos therein, for conventional geology mandates that this process happened countless times during the presumed evolutionary course of earth history. On the other hand, if the granites and the enclosed polonium halos are the Creator’s handwriting, then I say it is impossible for man to reproduce them. Neither Wilkerson, nor his associates, nor anyone else has reproduced granite, much less granite with polonium halos. Their collective failure to do this, coupled with the fact that granite melted in the earth cools to form rhyolite and not granite, signifies that the Creator left unambiguous evidence of His creative power when He called this earth into existence about 6000 years ago.

Robert V. Gentry

Earth Science Associates Box 12067

Knoxville TN 37912


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