|Thousands. . . Not Billions
by Don DeYoung
A review of the book, by
Stanley Robertson, Ph.D.
Both the motivation and the message of this book is that the earth and its inhabitants date back only some 6000 years. The motivation originates in interpretations of Genesis 1:1 - 2:3 in the Bible. For this interpretation to be correct, numerous scientific studies that have attributed older ages to various rocks and other artifacts must be in error. It is the intent of the author, Dr Don DeYoung, and his collaborators in the RATE (Radioisotope Age of The Earth) project to show that the widely used radioisotope dating methods are in error. In the author’s own words: “It is a bold endeavor, to be sure, to account for the alleged 4.56 billion years of conventional earth history in a span of about 6000 years.” (p. 138)
The apparent great age of some rocks is based on the assumption that some nuclear isotopes have decayed at such slow present rates that it would have taken these long times for the observed quantities of decay products to accumulate. DeYoung argues that the decay rates have not been constant at all. He surmises that decay rates were accelerated during the week of creation of the earth and again during Noah’s flood. If one is willing to accept miraculous alterations of some fundamental physics, then this might be accepted. But it also requires acceptance of other miracles such as dissipation of the huge energies released by accelerated nuclear decays without appreciable heating and also no heating caused by accelerated exothermic accumulations of massive limestones, assumed deposited in the flood. To the extent that these miracles are accepted, there is little point in continuing a scientific examination of the question. If the normal laws of science have been suspended, then it is unlikely that we will learn anything useful by continuing to assume that they apply.
Nevertheless, DeYoung and collaborators prepared about 60 rock and mineral samples for conventional radioisotope age determinations. To their credit, they contracted the actual measurements to independent laboratories. The results that they obtained in some cases were in moderate disagreement with ages reported in the available science literature by other workers. Although they made much of the discrepancies that they found, there is little to be concerned about. For example, a 100 million year discrepancy in age is considered to be bad, even though it was obtained for a rock of accepted age of about 2450 million years. Similarly, excluding one clearly discrepant K - Ar date of 842 million years, the mean of their measurements for the Bass Rapids sill (Grand Canyon) disagrees with the results obtained in previous studies by only 6% on a time of 1070 million years. The results that they report, along with the discordant cases they are overly concerned about could and should be published in mainstream geophysical journals. But it is unlikely that experts in the field would concur that everyone’s results are in error by a factor of a million or so. It is even less likely that they would be able to publish their speculations, without evidence, that the error is due to non-constant nuclear decay rates.
The book raises one interesting mystery: the occurrence of “orphan” radio haloes possibly produced by the decay of polonium isotopes, without apparent benefit of parent uranium nuclei. The author proposes that the polonium might be transported away from its parents by hydrothermal flows, but this seems unlikely due to both short half-lives and impermeability of the rocks, which are presumed already crystallized, else their temperatures would be so high as to anneal away the radiation damage. In fact, it is not accepted that the haloes in question originate with polonium or even that they are caused by radioactivity at all.
A second “mystery” concerns the apparent occurrence of C-14 in materials which are supposed to be so old that they would be radiologically dead. The half-life of C-14 is only 5,730 years. As noted in the book, the detection of C-14 by mass spectrometric methods is limited to about one part in 10^16 of carbon in a sample. This is basically a limit imposed by instrumental noise. On the other hand, present concentrations of C-14 in living matter are about one part in 10^12 of carbon. Thus instrumental noise limits are reached when C-14 concentrations have been reduced about 10,000 fold, to a few parts per ten thousand of modern C-14 concentrations. This reduction would occur after passage of about 13.3 half lives, or about 76,000 years. Although Dr. DeYoung takes the apparent occurrence of C-14 in older samples as evidence that they are really younger, it seems clear that all that has been found is instrumental noise.
While questioning the reliability of the radioisotope methods, DeYoung uses a strange mixture of young earth and conventional geological time scales to describe some of their sampling. For example, on p. 132: “Some magma bodies begin their journey upward toward the earth’s surface from the upper mantle, 10 - 40 miles below ground. Other magma begins as pockets or chambers of melted rock well above the mantle and within the crust. Magma is less dense than the overlying rock due to its high temperature, chemical makeup, and dissolved gases. These factors give the magma buoyancy as it ascends through the existing rock strata, either slowly or rapidly. The underground appearance of this moving molten plume might resemble a large distorted bubble, similar to the rising globule in a lava lamp. The magma may eventually cease its upward movement and cool underground to form solid rock.”
It is clear that the author has given no consideration to the time required for these processes to occur naturally. According to conventional geological calculations, magma plumes may take millions of years to ascend, and hundreds of thousands or more to cool and solidify, even if within a kilometer of earth’s surface. And in this case, hot springs would be found in the area for hundreds of thousands more years. Again, we are forced to conclude that if these events occurred within a six thousand year period, the process had to be not natural, but supernatural.
Although accelerated nuclear decay rates are mentioned at several places within the book, there is no serious evidence presented to show that they ever occurred. DeYoung and collaborators suppose that unexpectedly high concentrations of helium (produced by alpha decay) in some zircon crystals indicates that the helium was produced recently. Otherwise, it would have diffused away. They conclude that we either fail to understand helium diffusion in solids or that accelerated decay of uranium and thorium produced the helium recently. The high helium concentrations are not found in all zircons from every locale.
It is my opinion that the first option is the more likely. The escape of helium from crystals is a quantum mechanical barrier penetration process. The escape rate is dependent on the nature of the crystal boundary barrier and on the surface area upon which the helium may impinge. One of my favorite tales concerns an experiment in which helium was contained in a high pressure vessel, but it escaped at a disturbingly high rate. To counter this, a pressure vessel with thicker walls was built, and then the leak rate through its larger surface area increased. Diffusion of gases in solids is such a tricky business that it seems much more likely than nuclear decay to be misunderstood.
DeYoung states that nuclear decay rates could be altered by factors of 100,000 by only a ten percent change in the strong nuclear force that binds nuclei together. But such a change would have other observable consequences. A mixture of very sensitive laboratory experiments and astronomical observations that are less accurate, but go back further in time have failed to find evidence of such changes in fundamental physical constants.
Although there are several minor points within the book that could be discussed, it seems that one must take its major points of a young earth and accelerated nuclear decay as matters of faith. It clearly requires miracles, not science, for these to be true. But before finishing this review, it seems to me to be worthwhile to state for the record, what science seems to say about the age of the earth.
There are simple, hard to question evidences of an earth older than 6000 years. To begin, there are tree growth rings that can be counted to well beyond 6000 years. There are seasonal varve deposits of silt that became the Green River shale, whose layers can be counted into the millions. There are clear records of magnetic field reversals of earth. These are displayed in vertically stacked layers of sediments and lava flows on continents and also on symmetric horizontal stripes of magnetic polarity on opposite sides of the mid-ocean ridge system (which, at some 40,000 miles long, is earth’s largest geological feature). The ages of sea floor basalts, as determined by isotope dating techniques, are progressively greater at progressively larger distances from the ridge system. The magnetic striping of the basalts is a good analog of a magnetic recording with a tape moving past a recording head magnet. In this case, the rocks solidify, freezing in their magnetic fields aligned with the prevailing magnetic field of earth at the time the magma solidifies at the ridge. The spreading of the sea floors carries the rock away from the ridge system. The sea floor spreading is the mechanism of continental drift. It leaves the sea floors younger than the continents, but progressively older at larger distances from the ridge system. The match of continental features across ocean basins separated by a ridge, such as South America and Africa, is so complete that it is as though one tore this page and then, by matching pieces along the tear, found that the lines could be joined and read. The theory of sea floor spreading, plate tectonics and continental drift is completely consistent with an old earth and the geologic time scale that rests on radioisotope dating of minerals. The choices are to believe that interlocking, consistent pieces of evidence are substantially correct, or to believe without evidence that it is all in error due to miraculous alterations of the presently known physical laws.