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Robert Gentry, M.S.Reprinted by Permission of the Creation Science Fellowship, Inc., Pittsburgh, Pennsylvania, U.S.A., from the Proceedings of the 1986 First International Conference on Creationism. (See Credits)[Note: The main text in this report is identical with the first part of my AAAS report given on pages 269-283 of this Appendix, and is not repeated here. Instead we go directly to the Discussion and Closure sections.] [The Discussion section features objections and criticisms offered by three scientists. The Closure section consists of our responses to these objections and criticisms.] DiscussionAttempts to find radiohalos in meteorites and moon rocks have been unsuccessful, although both galactic cosmic ray and solar cosmic ray tracks have been found in appropriate crystals from each of these sources. The limitation of radiohalos to earth minerals of hydrothermal classification suggests that water may be essential to the process(es) by which radiohalos are formed. The location of radiohalo centers in mica along conduit paths and cleavage planes supports this inference. The existence of mature uranium halos in association with unsupported polonium halos presents a problem for a view that limits the real time ages of all minerals to less than 10,000 years. A 5 micron radius sphere of pure uraninite as a radiohalo center would require in the order of 3 million years to produce sufficient alpha particles to develop the minimum crystal disordering for a detectable 33 micron radius radiohalo (Polonium-214). A 3 micron radius sphere of monagite with one uranium impurity atom per unit monagite lattice element would require about 190 million years to develop a minimally detectable 3 micron radius radiohalo in mica. Thus the in situ creation of polonium impurity centers for unsupported polonium radiohalos and uranium impurity centers for mature uranium radiohalos at any time within the last million years also requires the uranium centers and are in every way indistinguishable from halos that would be produced by the uranium decay series as presently observed. For many individuals such a scenario requires the Creator to produce unnecessary "evidence" for events that did not occur in reality. In presenting to the public at large, or any segment thereof such as the scientific community, the Biblical creationist interpretations set forth in this paper, it is desirable to recognize that Polonium halos are definitive evidence of instantaneous, in situ creation only if one has perfect and complete knowledge concerning all other possibilities. Such knowledge may be possessed only by deity. The present limits to human knowledge do not justify asserting that there are no possible circumstances under which the regular processes maintained by the Creator could have progressively deposited Polonium within some samples of granite, comparable to the much more readily understandable accumulation at Polonium centers in "coalified" wood. If the polonium for unsupported polonium radiohalos in granite was an in situ primordial creation at halo center sites, it would be the only known primordial appearance of an element with other than a complete spectrum of isotopes. Polonium has 26 isotopes, all of which are radioactive. The 5 longest half-life members of this family, together with their half-lives and stable end products are:
According to the well-established empirical relationships between isotope abundance, half-life, and binding energy per nucleon, primordial polonium would be composed largely of its longer-lived isotopes, and its residue would be principally thallium 205 and lead 204. However thallium has never been reported as a polonium radiohalo center constituent, and lead 204 may be absent also [Robert V. Gentry, Nature 252 (Dec. 13, 1974), pp. 564-566; Annual Review of Nuclear Science 23 (Dec. 1973), pp. 347-362, specifically page 360]. Why is only lead 206 featured, the end product of uranium daughter products polonium 218, 214 and 210? The presence in uranium and polonium radiohalo centers of selenium, which would be precipitated also under conditions favoring the precipitation of uranium and polonium, favors explanation of radiohalos with processes involving solution transport of uranium and its daughter products, even though the details of such processes cannot be elaborated at the present lack of knowledge concerning hydrothermal environments and crystal formation [Norman Feather, Communications to the Royal Society of Edinburgh, No. 11, 1978, pp. 147-158]. Synthesis of a hand-sized piece of granite would prove that at least one laboratory procedure may be successful; it would be only suggestive, not definite, with respect to the actual processes that have determined the characteristics of a specific sample of natural granite. [p. 312] It is unsound to assert (p2, ¶3), without firm theoretical or observational support, that large variations in alpha decay rate were associated with alpha particles of unvarying penetration range. An explanatory model that contains such a requirement suffers a severe loss in credibility. The suggestion attributed to Gentry, et al., in the quotation from Norman Feather (p5, ¶1, reference 24) accounts for unsupported Polonium halos by radiation from daughters of hypothetical, extremely long-lived, extinct isomers of Polonium parents, not in terms of the fiat, in situ creation explanation given in this paper. A critical reader of the paper may wonder why Pb atoms are expected to be less tightly fitted into a Zr2SiO4 lattice than U and Th atoms. Since the He content of He-producing gas wells increases with well depth, it would be desirable to clarify the relationship between temperature, ambient He pressure, and expected He retention in zircons with U and Th impurity. In conclusion, this reviewer wishes to express appreciation for the discussion of Polonium halos in "coalified" wood that is given in this paper. Robert H. Brown, Ph.D. Dr. Gentry's years of excellent experimental work and observations on radiohalos make him without doubt the world's leading authority on them. However, I have a problem with his view that the "orphan" Polonium halos (the ones unaccompanied by halos from parent nuclides) must be primordial. Why (as Dr. Robert Brown has suggested) are the only orphan halos from Polonium isotopes in the Uranium decay series? Shouldn't there be some halos or daughter products from the other Polonium isotopes as well? It seems to me that there are other possible creationist explanations for the orphan halos. One which John Baumgardner, myself, and others have discussed has the following features:
This model is new and not well thought out yet. I cite it merely as a contrasting illustration. If someone rises to Dr. Gentry's famous challenge and synthesizes granite, it might prove that the halos are not primordial. But it would not prove that the halos were formed by natural processes working at present rates. D. Russell Humphreys, Ph.D. My essential criticisms of Dr. Gentry's halo interpretations have been published in more detail elsewhere (Physics Today, April 1983, 11-13). The main problems with his thesis are:
Assuming uniformity of physical laws is neither arbitrary nor circular: We live in a universe of patterns, and once a pattern is known to exist, the burden of proof is on someone who asserts that the pattern can change. When our checkbooks fail to balance, we do not assume lightly that someone has tampered with our account; we look for errors in our accounting instead. Similarly, we assume that unresolved problems in science will turn out to have a conventional explanation and only when the evidence becomes incontrovertible do we postulate changes in the laws of nature. As points (1) and (2) above indicate, Dr. Gentry's halos do not come anywhere close to this level of urgency. There is every reason to believe the halos have a conventional origin. In addition, there is no observational evidence that decay rates can change as drastically as they must to accommodate the creationist time scale; there is no theoretical basis for believing that they can change (Barry Setterfield makes a game try, but his treatment is full of errors). The paltry few percent change in electron-capture decay rates that creationists cite fall far short, in degree and in kind, of the million or so times that all forms of decay would have to speed up to reconcile creationist chronology and the radiometric time scale. Until creationists can demonstrate such enormous accelerations of decay beyond any doubt, and that probably means in the laboratory, most geologists will continue to be unrepentant uniformitarians. Steven Dutch ClosureReviews of scientific papers by competent scientists are of inestimable value in probing weaknesses and inconsistencies of a another scientists work, and thus are essential in the determination of scientific truth. By their very nature, reviews must be critical, even to the point of being highly critical, so that the scientific community will not be left in doubt concerning possible flaws in the work being reviewed. As many scientists can testify, the referee process required by scientific journals has saved many a reputation by exposing errors in technical papers prior to publication. At other times, however, that same process has also acted to prevent unpopular scientific truth from being published. Indeed, even these ICC Proceedings may contain things which would not pass muster in the open literature, and it might be said that in many cases the reason would be prejudice against the creation perspective. On the other hand, there is the possibility that some papers may have genuine flaws which need to be identified. This is all the more reason why creation scientists need to have their work examined and scrutinized by their peers. The history of Christianity has amply demonstrated that much done in the name of God bears little or no resemblance to the teachings of the Bible, or to the progress of truth. With this in mind I must—if I am really interested in the scientific truth as it relates to creation and evolution—have my findings, discoveries, and conclusions reviewed by those scientists who would be most critical of my work. This I have endeavored to do over the past twenty years as I have submitted my results to the secular scientific community for review and publication. The results of those endeavors have been recounted in detail in my recent book Creation's Tiny Mystery. There I attempted to provide a basis for laymen and scientists to arrive at an intelligent decision about the scientific validity of my discoveries of evidence for creation and a young age of the earth. As necessary as it has been for my work to go through the referee procedures mandated by the secular scientific community, I consider it just as necessary for it to be scrutinized by the reviewers chosen by the organizing committee of the ICC. The article I submitted for these ICC Proceedings is part of a paper originally published in 1984 in the Proceedings of the Sixty-Third Annual Meeting of the Pacific Division of the AAAS. At that time I requested a vigorous response to the evidences for creation and a young age of the earth summarized therein. None was forthcoming; so I am pleased that critical reviews have now been given by three respected scientists and even more pleased that one is an evolutionist. My intent in responding to those reviews is again to provide a basis for laymen and scientists to evaluate the scientific validity of my discoveries of evidence for creation and a several-thousand-year age of the earth. At the outset I wish to emphasize my personal esteem for all the reviewers. This is needful because in order to clarify matters it has been necessary to take strong exception to parts of some reviews. In certain instances, ideas and assumptions are introduced which differ considerably from my views and my creation model, and then these ideas are used to raise questions about the scientific implications of my research for creation. Some background information on halos is given below so that the reader can intelligently evaluate ny responses to these ideas. [p. 314] Experimental results published over the last 20 years show that polonium halos exist in Precambrian granites independently of any other type of radioactivity; thus I have said they are evidence of primordial polonium—meaning polonium that was created independent of, and separate from, any decay products in the uranium decay chain. The existence of primordial polonium halos in Precambrian granites identifies these rocks as part of the primordial Genesis rocks of our planet. In other words, primordial radioactivity and primordial rocks were created simultaneously when God called the earth into existence during creation week. In contrast, the evolutionary theory of the origin of the Precambrian granites supposes that these rocks crystallized from a slowly cooling magma over eons of geological time. Fortunately, there is an experimental test by which the origin of the granites can be settled. It is also a test which has devastating consequences for the theory of evolution. The basic premise of the entire theory of evolution is the uniformitarian principle, which is the assumption that the cosmos, including the earth, came to its current state solely through the action of known and unchanging physical laws. (Some readers may be more familiar with the term principle of naturalism.) The practical application of the uniformitarian principle to evolutionary geology implies that the Precambrian granites repeatedly formed naturally throughout billions of years of geologic time—and by naturally I mean with nothing more than known physical laws to govern their crystallization. But if this theory of granite origin is actually true, then it should be possible to reproduce this type of rock today by melting a piece of granite and allowing it to cool under suitable laboratory conditions. The end product should be another piece of granite similar to the original. If this could be done, evolutionists would be able to claim that the basic premise of their theory has some basis in fact, and I would withdraw my claim that the Precambrian granites were the Genesis rocks of our planet. In addition, if polonium halos could then be produced in that synthesized granite, I would also withdraw my claim that polonium halos in granites are primordial. After waiting almost eight years for the scientific community to respond to this falsification test, there still has been no demonstration of granite synthesis. It is certain that evolutionists would have performed this critical test long ago if it were possible for them to have done so. This impossibility can be traced to the fact that the fundamental premise of their theory—the uniformitarian principle—is not now, nor has it ever been, a sufficient basis for the Precambrian granites to form. In other words, both the Precambrian granites and the enclosed primordial halos required supernatural power to bring them into existence. Thus, irrespective of how many pieces seem to fit into the evolutionary scenario, the truth is that the uniformitarian principle is a false, hypothetical assumption. This background information is essential because parts of the reviews of Brown and Dutch rely heavily, either directly or indirectly, on this erroneous principle. For example, paragraph 1 of Brown's review implicitly utilizes the uniformitarian principle in an attempt to support a secondary origin of polonium halos in earth rocks. Before discussing how this is done, I note first that the mention of cosmic ray tracks in this paragraph is irrelevant to the topic under discussion, because cosmic ray tracks have no connection whatsoever with halos. Second, Brown omits some pertinent information when he refers to the absence of halos in meteorites and lunar rocks. For the benefit of the non-scientist who may not understand what this is all about, I should explain that in referring to meteorites and lunar rocks Brown is attempting to correlate the absence of halos with the absence of water. True, as far as we know, meteorites and the lunar rocks returned to earth do not contain water. What Brown does not say, however, is that most of these lunar rocks are not primary rocks, but surface rocks which recrystallized from molten material produced by meteorite impact. The absence of halos in lunar surface rocks is expected because any halos that might have existed in the original (pre-impact) lunar rock would have been destroyed by melting. Likewise, because of the vacuum on the moon, any water which might have existed in original lunar rock specimens would certainly have been lost during the high temperature phase of the impact process. Thus the general absence of halos in recrystallized lunar rocks is a natural consequence of the mode of formation of those rocks, and only incidentally related to the absence of water. In this context I should add that there is reason to continue the search for halos in lunar rocks. I think it is conceivable that halos may still exist in tiny, unmelted fragments of certain primary minerals contained within those rocks. Whether such fragments do exist in the lunar rocks now on earth will not be known until all those rocks are sectioned and carefully examined. Before discussing Brown's assertion about minerals of hydrothermal classification, I will discuss his evaluation of halos in mica, a mineral that is generally considered to be of this type. In his first paragraph Brown suggests, without any supporting evidence, that halo centers along conduits and cleavage planes in mica support a hydrothermal origin of halos in this mineral. (In other words, halos which developed from radioactivity captured out of a solution containing significant concentrations of radioactive elements.) This suggestion was [p. 315] initially made by some early investigators who worked on halos about a half a century ago. There were serious problems with this hypothesis then, and even more difficulties with it now. First, to associate halos in mica with a hydrothermal origin because their centers are along cleavage planes is meaningless because the crystal structure of mica is such that every center is situated along some basal cleavage plane. Secondly, there are numerous uranium and thorium halo centers in mica, such as monazites and zircons, which are not considered to be of hydrothermal origin (in the conventional usage of that term). Thirdly, Brown fails to say that the perfect cleavage properties of mica provided me with the opportunity over 20 years ago of examining the microscopic distribution of alpha radioactivity around polonium halo centers, and those studies showed no evidence for a secondary origin of polonium halos in this mineral. In fact, the report describing those results is cited in my ICC paper. I now turn attention to my respected colleague's comment about halos being found in earth minerals of hydrothermal classification. This comment is a clear reference to the standard uniformitarian supposition that many primary minerals formed over geological time by very slow crystal growth either in a magma containing water, or in aqueous solutions laden with the chemical elements of which the mineral is composed. Uniformitarian geologists adopted this belief long ago mainly because: (1) it is possible to use aqueous solutions to slowly grow crystals of some minerals in the laboratory, and (2) there was evidence that many secondary minerals in sedimentary deposits had formed in this fashion. Geologists merged these two observations together with the uniformitarian principle and went on to assume that the vast number of primary minerals found in the earth—here I refer to the minerals found in crystalline rocks such as the Precambrian granites and pegmatites—achieved their large size through a slow growth process. In my recent book, Creation's Tiny Mystery, I challenge the assumption that large crystals of primary minerals grew from small crystals over evolutionary time, and in particular refer to the existence of polonium halos as unambiguous evidence that these minerals were created. I also note in my book that evolutionary geologists should long ago have seen the falsity of this supposition both from the huge size of some natural crystals and from their inability to synthesize even reasonable size specimens of certain minerals such as biotite, an iron-rich mica which often contains radiohalos. Summarizing, the term "minerals of hydrothermal classification" does represent a correct description of origin when applied to secondary mineral formation in sedimentary deposits. On the other hand, it is incorrect when applied in the conventional geological sense to describe the origin of primary minerals. Thus, Brown's argument for a water-related origin of halos in those minerals is invalid because it is based on the erroneous assumption that primary (or primordial) minerals developed through slow crystal growth over geological time. For further clarification of the preceding paragraph, I should emphasize that, as might be expected, in the context of my creation model certain terms have a different meaning. With this new meaning there may be a definite relation between primary minerals and "minerals of hydrothermal classification." In my book, Creation's Tiny Mystery, I referred to the creation of earth's primordial rocks in the context of an instantaneous crystallization of a primordial liquid. More precisely, I envision there were a variety of primordial liquids called into existence on Day 1 (and perhaps Day 3) which gave rise to various types of primordial rocks. In my opinion, 2 Peter 3:5 strongly suggests that these primordial liquids must have included water at some instant in time within the creation process. In this sense the primordial (primary) minerals created on Day 1 (and perhaps Day 3) of creation week could also be viewed as "minerals of hydrothermal classification." Skipping over paragraph 2 momentarily, paragraph 3 expresses some of my colleague's philosophical views, and he is certainly entitled to those opinions. Moreover, any scientist has a right to formulate any hypothesis he chooses about creation, and he is entitled to use the data published in my reports in this endeavor. However, if my data are used, then that scientist should be careful to state just where his own assumptions are introduced into his interpretation of my data, and in addition, he should make it quite clear that the conclusions obtained with these different assumptions are separate and distinct from my views. Unfortunately, that distinction is not clear in several places in Brown's review of my ICC paper, hence the need for extensive clarification on my part. Paragraph 2 is one place where such clarification is essential. Brown introduces his second paragraph by stating that the existence of well-developed uranium halos in association with polonium halos presents a problem for a view that limits the age of all minerals—or equivalently, the age of the earth—to less than 10,000 years. In Figure 1(a) and 1(b) I show two examples of the specific association of halos to which my colleague refers in the above statement. (Readers desiring further information about these halos should refer to the photos in my ICC paper.) [p. 316]
Given the above information, we need to understand why Brown asserts the association of uranium and polonium halos presents a problem for a young age of the earth, and then determine whether the reasons for that assertion are scientifically valid. The basis for his assertion is found in the second sentence of paragraph 2. There the claim is made that it would take from 3 million to 190 million years to produce well-developed (mature) uranium halos. In other words, Brown attempts to call into question a young age of the earth by saying that it must have taken millions of years for uranium halos to form in the minerals in which they are found. He fails to say, however, that the millions of years that he claims are needed for uranium halos to develop is neither a scientific fact, nor a part of my creation model, but is instead a deduction at which he arrives by assuming a uniform radioactive decay process throughout geological time. But as discussed in my book, the assumption of uniform decay is just a corollary of the fallacious uniformitarian principle. In other words, the millions of years which Brown assigns to the development of uranium halos are imaginary because they are computed on the basis of a false assumption. Paragraph 2 of Brown's review concludes with a reference to the Creator producing unnecessary "evidence" for events which did not occur in reality. With all due respect, the reader should understand that here my colleague is arguing against a straw man of his own devising, for the scenario described in his second paragraph is completely foreign to my creation model. Specifically, he mentions the in situ creation, sometime within the past million years, of polonium centers for polonium halos, and uranium halo centers for well-developed (mature) uranium halos. At first glance this statement may seem to fit into my creation model, but this is an illusion. One irreconcilable difference between my creation model and the above comment is the reference to the in-situ creation of uranium impurity centers for well-developed (mature) uranium halos. In Brown's own words this "requires the uranium centers and halos are in every way indistinguishable from halos that would be produced by the uranium decay series as presently observed." But since the "the uranium decay series as presently observed" is undergoing uniform radioactive decay, then it seems that Brown is referring to the creation of uranium centers with characteristics which he interprets as evidence of uniform radioactive decay over an extended period of time. This whole idea is foreign to my creation model. Nowhere do I propose that uranium halo centers were created with the characteristics associated with uniform radioactive decay over an extended period of time. Such a scenario implies, first, that the uranium centers were created with artificial characteristics, and second, that uranium halos in granites were not produced by alpha-particle interaction with those rocks, but instead are just colorations which were directly imprinted into them. This view is conceptually, philosophically, and scientifically at variance with two major tenets of my creation model—namely, (1) that polonium halos are genuine evidence of an instantaneous creation of the Precambrian granites precisely because alpha particles emitted from rapidly decaying primordial polonium atoms did produce polonium halos in those rocks (in other words, polonium halos are truly autographs of radioactivity that had only a [p. 317] fleeting existence), and (2) that uranium and thorium halos likewise resulted (via an accelerated decay process) from the interaction of alpha particles from uranium and thorium centers that were created simultaneously with the granites. In my model uranium and thorium halos are post-creation entities which formed via an enhanced radioactive decay process during one or more of the three biblically-based singularities described in my ICC paper. On this basis, I can easily account for the close association of uranium and polonium halos,, such as shown in Figure 1. I must conc~ude, therefore, that the problems cited in the second paragraph of Browns review concerning the association of uranium and polonium halos are due primarily to his use of the errcneous uniformitarian principle and the associated uniform decay rate assumption, and secondarily to the introduction of an idea which is completely foreign to my creation model. In paragraph 4 Brown argues for a secondary rather than a primordial origin of polonium halos in granites, but unfortunately he overlooks nearly all the scientific evidence which negates this hypothesis. Through many experiments over the past two decades I have shown the unequivocal differences between the secondary polonium-210 halos in coalified wood—meaning those that resulted from water transport of uranium daughter activity—and the several types of primordial (independently created) polonium halos in granites. Brown does not at all deal with the vast differences in uranium content and transport rate between granites and gel-like wood (the early stage of coalified wood), nor in any way attempt to provide experimental evidence for a secondary origin of polonium halos in granites. Instead, he argues against a primordial origin of polonium halos in granites using arguments which appear to be based on scientific fact. The following discussion presents another view of those arguments. In the beginning of paragraph 4 Brown argues against primordial polonium halos using an idea initially proposed several years ago by one of the other reviewers (Dutch). His main line of argument utilizes a particular concept of the isotopic composition of primordial polonium. Using this concept Brown arrives at what he feels should be the composition of halo centers at present, and then notes that I have not reported such compositions. All this leaves the impression that something must be wrong with my conclusion that polonium halos in granites are primordial. Unfortunately, some very important information was omitted from Brown's discussion. We shall see that the picture changes considerably when all the pieces of the puzzle are included. Readers should understand first that I have never said, or even remotely suggested, that primordial polonium would be composed of the isotopes cited in paragraph 4 of Brown's review. His definition of primordial polonium is quite different from mine, and the reader is entitled to know the reasons why the two are fundamentally different. What my colleague has done—apparently unwittingly—is to combine two results from experimental physics together with a theoretical result of the evolutionary Big Bang model, and then lumped everything together as if it is based on experimental nuclear physics. In particular, Brown claims "well-established empirical relationships between isotope abundance, half-life, and binding energy per nucleon . . ." establish the composition of primordial polonium as he states it. If all parts of this statement were true, there would be some scientific justification for Brown's version of primordial polonium. The problem is, however, that one crucial part of the above statement is not true. Specifically, while nuclear physics has established empirical relationships between half-life and binding energy per nucleon, it definitely has not established a pattern of primordial isotope abundances as Brown claims is the case. The pattern of isotope abundances to which Brown refers—which also forms the basis of his definition of primordial polonium—is in reality the end result of theoretical calculations pertaining to the Big Bang theory of the evolution of the universe. To understand Brown's version of primordial polonium the reader needs to understand how cosmologists view the origin of matter. First, because modern cosmologists believe only the two lightest elements—hydrogen and helium—were made in the Big Bang, they must find some way to account for all the heavier elements in the universe—including those composing the earth, sun and planetary system. Their theory is that these heavier elements were formed billions of years ago in fusion reactions deep inside certain stars. As explained in my book, they also believe interstellar space became sprinkled with heavier elements as more and more stars exploded through eons of time. Then, through processes which have never been clearly defined, supposedly the remnants of these violent explosions somehow reaccumulated to form other stars, one of which is assumed to have been the proto-sun, the forerunner of both our sun and the earth. Here we must pause to separate fact from assumption. It is doubtless true that some chemical elements are produced in stellar fusion reactions—by charged particle reactions, or by slow neutron capture (the s-process), or by rapid neutron capture (the r-process)—but it is [p. 318] just sheer fiction to assume that all the heavier elements in the universe were produced by such reactions. But this is what modern cosmologists do, and on this basis they proceed to theoretically calculate the primordial isotopic abundances of all the heavier elements. Such patterns of isotope abundances are only theoretical patterns because they involve several unverified assumptions about the exact path by which fusion build-up of the heavier elements is thought to have occurred. I should add that what correspondence there is between the most commonly accepted theoretical abundance pattern and the actual abundance pattern as measured on earth is the result of varying the parameters in the theoretical calculations to fit the measured abundances. (Readers desiring more details on how isotope abundance calculations are linked to various aspects of the Big Bang theory may consult an older publication, Nuclear Astrophysics, authored by Nobel laureate William A. Fowler, and published by the American Philosophical Society, Philadelphia, 1967, or a more recent one, "Nucleosynthesis and its Implications on Nuclear and Particle Physics", Proceedings of the NATO Advanced Research Workshop on Nucleosynthesis and Its Implications on Nuclear and Particle Physics, Les Arcs, France, March 17-23, 1985, 0. Reidel Publishing Company, 1986.) The above discussion shows that the theoretical isotope abundance pattern used by Brown to formulate his version of primordial polonium and its most prominent decay product, thallium-205, is hinged on the assumption that the heavier chemical elements on earth—specifically including polonium—originated in stellar nucleosynthesis. Using that assumption Brown interprets the absence of thallium-205 in halo centers as indicating the absence of primordial polonium, hence implying that something is wrong with my identification of primordial polonium halos. Here a most important point needs to be emphasized. There is another explanation for the absence of thallium-205 besides the one Brown has mentioned, namely: Instead of the missing thallium-205 indicating something is wrong with my identification of primordial polonium halos, what it actually shows is that the Big Bang version of primordial polonium is without any scientific basis. We should ever remember that the validity of a theory is determined on the basis of whether it agrees with the relevant experimental facts, and in this case it is abundantly clear that the Big Bang version of primordial polonium does not agree with the experimental facts. Therefore, I reaffirm that polonium halos in granites did form from the decay of primordial polonium-218, polonium-214 and polonium-210, and this is why halo centers feature the decay product lead-206. (Halos from bismuth-212/polonium-212 also exist but are much rarer than those just listed.) I believe these types of polonium halos are evidence that the true isotopic composition of primordial polonium—meaning the polonium God created when He called the earth into existence—was irreconcilably different from that expected on the basis of the Big Bang model. In other words, when God called the earth into existence He left unambiguous evidence of His creative power which could never be confused with the Big Bang scenario. (Readers interested in knowing other reasons why the Big Bang model is wrong should consult the more extended discussion given in my book.) On a different subject in paragraph 4, Brown refers to the presence of selenium in both uranium and polonium radiohalo centers, and the assertion is made that this is evidence for the explanation of halos involving solution transport of uranium daughters. The first problem with this view is that selenium is definitely not a constituent of uranium radiohalo centers, and it is not clear why such a claim would be made. (In fact, one of the other reviewers, Dutch, correctly notes that Group VI elements, which includes selenium, are not geochemically compatible with the U- and Th-bearing minerals that normally constitute U and Th halo centers.) Secondly, only in a very few cases have I observed selenium in the centers of polonium halos in granites. Possibly Brown generalized the results given in my 1974 Science report and incorrectly inferred that selenium in polonium halo centers in granites is the rule rather than the exception. Thus, all the arguments cited in this paragraph in support of a secondary origin of polonium halos in granites are based either on ideas or suppositions which are foreign to my views, or on incorrect interpretations of my published data. In paragraph 5, my respected colleague does not directly comment on the implications of the falsification test as I have defined them, but instead generates his own interpretation predicated on the assumption of a successful outcome of that test. Brown is entitled to his views, but he fails to mention the evidence which contradicts the assumption of a successful outcome—namely, that, according to conventional theory, the conditions for reproducing granite from a granite melt have existed in nature countless times, yet the end result is rhyolite, a fine-grained, non-halo-containing rock that is quite different from granite, a coarse-grained rock which does contain halos. Additional explanation is given in my book, Creation's Tiny Mystery (page 130). [p. 319] In paragraph 6 of his review, Brown claims my model of enhanced alpha decay suffers a severe loss of credibility. But this conclusion is obviously based on his acceptance of uniform radioactive decay rates—a direct consequence of the uniformitarian principle. Thus, this particular criticism results from his acceptance and use of a fallacious assumption. Paragraph 7 could easily be interpreted as a correction to an erroneous claim on my part, but the fact is that my comments about Feather's evaluation are correct as they stand. In answer to paragraph 8, U and Th atoms are more tightly bound because they are part of the zircon lattice structure. The Pb atoms, on the other hand, being the radiogenic end-products of U and Th decay, are rather loosely bound primarily because they have been displaced about 100 angstroms (by recoil from a series of alpha emissions) from the original U and Th lattice sites into a region where lattice disruption has occurred. Paragraph 9 refers to the helium content of helium-producing wells. These may have their source in secondary uranium deposits, that is, uranium which has been separated from primary uranium-bearing minerals and widely dispersed via solution transport. A prime example of secondary uranium deposits are those of the Colorado Plateau. Helium migration occurs without difficulty from such deposits because of the dispersed state of uranium and its daughters. There are two reasons why helium migration from zircons in granites is much lower than from helium escape from these secondary deposits. First, there is the difference in uranium content. Zircons, which may contain only about 100 ppm (parts per million) of uranium, are encased within granites containing an even smaller concentration of uranium, usually about several ppm. These concentrations are generally much lower than the uranium concentrations found in many secondary uranium deposits. Secondly, migration (or diffusion) from zircons has been found to be relatively slow at ambient temperatures, a fact which is attributable to the crystalline structure of this mineral. These two factors account for helium effusion from helium wells being significantly higher than helium diffusion from zircons. Thus nothing in this paragraph contradicts my claim that helium in zircons taken from deep cores is very strong evidence for a several-thousand-year age of the earth. About paragraph 10, I appreciate the compliments about my work on halos in coalified wood. Of course, the analytical techniques that were used to investigate polonium halos in coalified wood were the same as those used to investigate primordial polonium halos in granites. In summary, I thank Dr. Brown for presenting his detailed objections in print, thus enabling me to clarify to the scientific community some issues that have long been misunderstood. And in closing my response to his review, I again express my respect and admiration for him personally. Turning to Dutch's review, part (1) reveals how easy it is to arrive at erroneous conclusions when reading someone else's reports. It is true that U and Th halo radiocenters are generally known U- and Th-bearing minerals, but Dutch displays a lack of knowledge of radiohalos by erroneously assuming these minerals also form the centers of polonium halos. The data I have published, especially in my 1974 Science and Nature reports, show that polonium halo radiocenters in granites are quite distinct from the usual U- and Th-bearing minerals found at the centers of U and Th halos. Other unpublished results of mine are in agreement with these findings. Thus, when Dutch argues against polonium being in U- and Th-bearing minerals, he is arguing against a straw man of his own invention. Part (2) in essence disputes the conclusion that polonium halos in granites are primordial on the basis that halos from other polonium isotopes should also be present if this were the case. Dutch has produced no scientific evidence to contradict the existence of primordial polonium halos in granite. Instead he has introduced a hypothetical phenomena into the discussion—namely, of what he thinks primordial polonium should consist—and then claims that my model must be wrong because it doesn't include his hypothetical component. This is, of course, exactly the same argument that Brown used in paragraph 4 of his review. As I showed in my lengthy response to Brown's paragraph 4, the fallacy in this whole idea is the assumption that the Big Bang version of primordial polonium is correct. Indeed, as I indicated in the conclusion of my response to Brown's paragraph 4, the isotopic composition of lead in polonium halos in granites provides unmistakable evidence that the Big Bang version of primordial polonium is fictitious. As mentioned previously, I have provided abundant scientific evidence that some polonium halos in nature are secondary—referring to the polonium-210 halos found in uranium rich coalified wood specimens from the Colorado Plateau—and have shown in detail how these halos differ from the primordial polonium halos in granites. For some reason Dutch omits any mention of these differences from his review. In part (3) Dutch attacks my creation model because it includes elements of uniformity and nonuniformity. It should be noted that his attack is based on philosophical rather than [p. 320] scientific grounds. I make no apologies for proposing a model that includes both uniformity and nonuniformity because this is what the scientific evidence dictates. What Dutch avoids saying is that my model can account for both primordial polonium halos in granites as well as secondary polonium halos in coalified wood, which is something the standard evolutionary model can never do. What is most interesting in this paragraph is the way Dutch first raises questions about the identification of polonium halos using the uniformitarian aspect of my model, but then admits my identification of polonium halos is correct after all! The last point in this paragraph concerns whether decay rates may have speeded up or slowed down. My response is that the evidence from the U/Pb ratios in coalified wood, as well as the results from both the Pb and helium retention in zircons taken from deep cores, provides strong evidence that the earth's age is very young. This implies an enhancement in the decay rate in the past. The last paragraph of Dutch's review starts out as a philosophical defense of the uniformitarian principle, with the implication that evolutionists have the truth. With this mind-set Dutch then proceeds to relegate all my discoveries for creation to the category of "unresolved problems in science." He claims that scientists will only revise their beliefs after they are confronted with incontrovertible evidence to the contrary. But somehow he fails to see that evolutionists have been confronted with just that kind of evidence for a long time—the falsification test was proposed almost eight years ago. Clearly, when the issue between creation and evolution was reduced to the outcome of an experimental test, evolutionists signally failed—and are continuing to fail—to meet the challenge of creation. Dutch's comments about variable decay rates reveal again, unfortunately, that he continues to utilize the straw man approach—this time erecting two of them—as a means of attacking my work. As just noted (two paragraphs ago), the evidence cited for a change in the decay rate is based on the U/Pb ratios in coalified wood and the results of Pb and He retention in zircons taken from deep granite cores. I also cite the existence of primordial polonium halos in Precambrian granites of presumably varying geological ages as prime evidence that the different radiometric ages of those granites are fictitious. But I oppose the idea that it is possible to produce significant decay rate changes at present. Dutch must surely realize that this is my position because the creation model I have proposed—and about which he comments—pictures significant decay rate changes only in the context of supernatural intervention into the affairs of this planet during such periods as creation week and the time of the flood. From this it can be seen that the whole Idea of inducing significant decay rate changes at present is diametrically opposed to the basic tenets of my creation model. Near the end of his review Dutch begins to critique other creationists' views of radiometric dating, including a reference to changes in electron-capture decay rates. I do not understand why these remarks are included in his review because all the views that Dutch comments on here are quite different from mine, and in fact are completely disassociated from my results. Finally, I again express my personal esteem for Dutch. And in response to his last sentence, I would hope that he—and for that matter all who hold a purely uniformitarian view of earth history—would carefully consider that God left scientific evidence of creation to help those who doubt Genesis come to a full knowledge of the truth of His Word. In considering Russ Humphrey's review, aside from the question about other polonium halos—to which I have already responded in the preceding reviews—it appears to be mainly an outline of a tentative model conceived by Russ and John Baumgardner. There are some similarities between their model and mine—we both incorporate some form of change in the radioactive decay rate into our models. This means that we both recognize the uniformitarian principle is not a valid premise for reconstructing earth history. The significant differences between our models, as I understand them, are as follows:
Without further discussion about the differences between our models, the most important question is whether their model can account for the existence of polonium halos in granites. The first problem is of course to identify the source of uranium for the polonium. For polonium halos embedded within a large granite formation it is in many cases difficult, if not impossible, to find a significant concentration of uranium nearby. Then comes the question of transporting polonium through the solid rock. The movement of radioactivity via solution transport is certainly valid for gel-like wood, but quite difficult to justify for movement through granite. Ordinarily this must be done by diffusion, an exceedingly slow process, which when considering the time between the Fall and the Flood, would imply only small distances would be traversed. Perhaps the most difficult obstacle to the formation of polonium halos in this tentative model seems to be inherent in the model itself. That is, if decay stops after the Fall, then polonium is a stable element with the ratios of the various polonium isotopes fixed in the proportion that existed at the time decay ceased. Thus all isotopes of polonium would move in unison (chemically speaking) and there would be no isotopic separation at all. The same is true for the lead and bismuth beta-precursors of polonium. This means that, if decay restarted at the Flood, there would be only one type of polonium halo (polonium-210) from the uranium series rather than the three types which actually exist. The reason for this becomes apparent when it is realized that during the period of decay the isotopic abundances of polonium-218, -214, and -210, bismuth-214 and -210, and lead-214 and -210, are determined by the half-lives. For all three elements the 210 isotope has a half-life that is several hundred times greater than the 214 or 218 isotope. This means that in every case where polonium, bismuth, or lead may be separated as an element in a radiocenter, the 210 isotope of that element will be in vastly greater abundance than the 214 or 218 isotope, and thus lead to the formation of polonium-210 halos in every instance. In other words, there would be no possibility of halos originating solely with polonium-218 or polonium-214 to produce either a balanced-coloration three-ring polonium-218 halo or a two-ring polonium-214 halo. Examples of these balanced-coloration polonium-218 and polonium-214 halos are shown in the radiohalo catalog in my book. Finally, since Russ ends his review with comments about the falsification test, it is appropriate to relate two new items about this topic. In the first instance a friend recently informed me that a California geologist had claimed one of the geology films distributed by Ward's Natural Scientific Establishment, Inc. showed granite synthesis. Subsequently, I contacted the producer of the film, Mr. Silas Johnson, now retired, of Coronado, California. According to Johnson this film is mainly an overview of geologic history explaining in general terms the conventional view of the origin of igneous rocks. The film was designed for the high school level and contains nothing relating to the experimental synthesis of granite. Another report is far more interesting. A Canadian evolutionist wrote me, and sent copies to a number of prominent evolutionists, that the geology course, Understanding the Earth, offered on TV-Ontario, features a film on igneous rocks that shows granite synthesis. I obtained a videotape of that film, which is program 3 in the Understanding the Earth series. The purpose of the series is to educate students in the conventional, uniformitarian view of earth history, including the idea that granites cooled slowly from a melt. As a means of accomplishing that purpose, program 3 shows a laboratory experiment that claims to duplicate conditions under which granite is thought to have formed. In the film granite powder is melted under pressure and then allowed to cool. The resulting specimen is said to show a resemblance to granite. The film does not claim that the cooled specimen is actually a granite. It states only that the experiment can be interpreted as being suggestive of how granites formed. To say the specimen resulting from a granite synthesis experiment just resembles granite, instead of actually being a granite, is exactly what the falsification test is all about. Thus, the Canadian evolutionist, who wrote to me about this TV program illustrating granite synthesis, erroneously equated an imitation granite with the genuine article.* From my viewpoint the results of this experiment have been one of evolution's best kept secrets—the experiment itself was done over twenty years ago—and it is now time for this particular secret to be given the widest possible exposure. As this response goes to press I am checking to see what, if any, additional details about this interesting experiment may be determined at this late date. In my opinion creation science is about to move into a new era. There are exciting posslbilities!* Robert V. Gentry [*As the UT presentation showed (pages 199-204), I was successful in locating one of the rock specimens here referred to, and it was not a granite. Creation science has moved into a new era.] |
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Earth Science Associates
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