The Unreliability of Radiometric Dating

By Jon Covey, B.A., MT(ASCP)
Edited by Anita Millen, M.D., M.P.H., M.A.

Most people, including scientists, assume that radioactive dating methods, such as Carbon-14 or Uranium, are very reliable. Because of this, they view young earth creationists as foolish—akin to those who believe in a flat earth. Many think all one has to do to date a rock is put it into a machine, then the machine will count the radioactive decay incidents and convert it into a date we can understand. Few people are aware of the assumptions that must be made and the widely differing dates that can be obtained from samples of the same rock, vastly older or younger than the "accepted" age of the rock based on the fossil record of the geological layer from which it came. Philosophical predisposition, whether creationist or evolutionist, determines the assumptions made. Most people, including most scientists, are unaware of the pitfalls in the radiometric dating methods.

The Young-Earth View Died with Lord Kelvin

Lord Kelvin (William Thompson, 1824-1907) opposed Darwinism. Probably the greatest physicist of his day, Kelvin argued that the earth could not possibly be as old as Darwinists insisted because the earth’s interior is far too warm for a planet that was molten over 4 billion years ago. Kelvin showed that the earth’s temperature indicated the planet could not be older than 100 million years while some contemporaries argued that it was no more than 10 million years old. [Burchfield]

The Encyclopaedia Britannica (1997 CD-ROM) gave this account:

"The publication in 1859 of the conclusions of Darwin and Alfred Wallace on the origin of species extended the principle of uniformity to the plant and animal kingdoms. Although the catastrophists continued to fight a rearguard action against the Huttonian-Lyellian-Darwinian view until the end of the century, a new criticism was raised by William Thomson (later Lord Kelvin), one of the leading researchers on thermodynamics. Thomson pointed out that the Earth is losing heat by conduction and that the nature of geologic processes may have changed as a consequence; he also concluded that this cooling placed an upper limit on the age of the Earth. With the discovery of radioactivity and the recognition that radioactive isotopes within the Earth provide a continuing internal source of heat, it became clear that Thomson’s conclusion that the Earth was less than 100 million years old was incorrect, but his argument that the Earth suffers an irreversible loss of energy remains valid."

When radioactivity was discovered by Becquerel in 1896, Kelvin’s opponents argued that the decay of radioactive isotopes produced the heat that kept the earth warmer than what it would have been if a molten earth began cooling over 4 billion years ago. Kelvin recalculated the cooling time for the earth based on this new information. Instead of showing that the earth had been cooling for 4 billion years, the new figure showed that the earth could not have been cooling for much more than about 100 million years. The scientific community, already won over to the evolutionary camp ignored his new calculations and placed its confidence in the radioactive dating methods. In Age of the Earth, Harold Slusher and Thomas Gamwell reexamined the time required for the earth cooling to its present temperature. They made five calculations for the cooling time based on a range of estimates, starting with presently known stores of radioactive materials in the earth. They concluded that even with unrealistically high estimates the earth could not have been cooling for more than one billion years. [Slusher]

Origin of Radioactive isotopes—divine or natural?

Where did the radioactive elements come from? According to evolutionists, about 8-16 billion years ago the Big Bang exploded, creating the universe. Initially, the universe was composed of about 90% hydrogen, 10% helium, and a trace of lighter elements such as boron and lithium. The Big Bang created little or no heavier elements such as iron and nickel. The heavier elements were created later in the fiery cauldrons of stars by the process of nucleosynthesis. Astrophysicists say that stars synthesize no element heavier than iron. They say it takes cataclysmic supernova explosions to create the radioactive elements geologists use to date rocks. Very hot, first generation stars formed about one billion years after the Big Bang and perished in brilliant explosions called a supernova about 100 million years later [Cowen].

Image of Supernova 1987a is courtesy of NASA

If all this is true, no one knows how long ago supernova created the universe’s main uranium supply or how long that supply has been decaying before it became part of the material that formed the earth. Most estimates for the age of the universe range from 10 to 20 billion years. A generally accepted age among evolutionary theorists is around 13 billion years. Some creationists dispute the origin of most long-lived radioactive isotopes, and affirm they were created along with the rest of the universe. Evolutionists suppose the case is closed on radiometric dating and the overwhelming evidence is in their favor—and nearly everyone knows that creationists are misinformed, mislead, or deluded.

How much lead was in the earth when it was formed?

Let’s assume the universe is about 16 – 20 billion years old. If a supernova created one ton of Uranium-238 (U-238) 16 billion years ago, how much of that uranium still exists? The half-life of U-238 is 4.5 billion years. This means after 4.5 billion years, one-half of the uranium atoms will decay into daughter products, ultimately Lead-206 (Pb-206). If we looked at that ton of U-238 today, we would find that almost 88% of it has since turned to Lead-206. Before the earth ever formed, 75% of the original uranium would have decayed. Most of that original uranium would have decayed to Lead-206 by the time the earth formed. If isotope geologists compensated for calculation of the earth’s age based on these figures, the earth would be dated much younger than it is.

How did scientists decide when supernovae created the majority of uranium? Part of the answer comes from the study of meteorites, sedimentation rates, mutation rates, cooling rate of the earth from a molten condition, and light’s travel time from distant galaxies. Evolutionists believe that the results from the various methods used are independently derived, making the age determinations that much more reliable. The blind spot in evolutionary thinking is the basic assumptions evolutionists make employing each method. Their strong bias for a very old universe causes them to make assumptions that will favor their bias.

Because evolution is believed to be true, the assumptions in each independent method must result in answers that provide a time interval amenable to the slow, stately pace of evolution which requires several hundred million years minimally.

Other solutions for the problem of measuring time passage since earth’s appearance are rejected if they do not confirm a long time interval that will allow the extremely slow process of evolution to occur.

Professor Richard Arculus assumes that 6.5 billion years ago supernovae created most of the uranium for our planet. He bases this on the belief that the earth is 4.5 billion years old and that the production ratio of U-235 and U-238 in a supernova is about 1.65. He says this is an oversimplification and concludes that about 10 supernovae from over 6 billion years ago to about 200 million years ago contributed to the uranium stores on earth to produce the unique ratio of U-235/U-238.

Evolutionists believe the earth formed by the gradual accumulation of leftover dust from the disk of gas and dust surrounding the protostar that became our sun. The origin of the material was from supernovae.

After the explosive supernovae some 6 to 15 billion years ago, the remnant gas and dust rapidly expanded outward. This material collided with similar material coming from other supernova and interstellar gas and dust left over from the Big Bang. Eventually, say astronomers, this material formed new stars like our own sun after several billion years. The uranium created in the supernovae began decaying immediately. Therefore, the amount of lead originally contained in the earth when it formed would have been 2-10 times the amount of uranium, depending on when supernovae created the main uranium stores incorporated into the earth. This is important to know because it will help us to decide whether geologists make fair assumptions for the initial amounts of lead and uranium in rocks they’ve dated. It seems it is impossible to ever know what were the initial amounts of U-238 and Pb-206. The same is true for dating methods using other isotopes.

The measured thorium and neodymium ratios of stars in our stellar neighborhood, if accepted at face value, strongly indicate that no significant amount of time has passed since the creation of these isotopes. Virtually all the initial thorium is still there, meaning not enough time has passed for significant decay of thorium. [Butcher] The spectroscopic evidence from 20 nearby stars presented by H. R. Butcher confirmed what Nobel physicist William Fowler advocated for many years: the universe was much younger than most astronomers accepted (see our article The Age of the Universe for more details).

Radiometric Discrepancies of the Geologic Column

John Woodmorappe lists over 350 radiometric dates known to be in error. [Woodmorappe, 1979] He compared the expected age of the material dated with the age obtained by the reporting scientists. The expected age is based on the rock layer from which the sample came, which is based on the specific fossils found in them. He explained that although very common, most discrepant dates are simply excluded from the published reports or explained away.

One must recognize that even if the number of discrepant dates greatly exceeded the number of accepted dates, many evolutionists, especially leading authorities, would tend to disregard the former results because they are firmly convinced of the earth’s antiquity despite contrary evidence. Gunter Faure, a leading isotope geologist, explained that geologists rejected the body of uranium/lead/thorium dates they obtained prior to the late 1950’s. [Faure, p. 282] How many discrepant dates must there be before it is admitted radiometric dating is invalid? Wrong question. Even if there were 100 discrepant dates for every "correct" date, geologists would still accept radiometric dating. What would cause them to lose confidence in the methods? A new, superior method that would provide them with ages that the geological establishment has already accepted. One geologist [Pilkey] says that criticism of the present methods is not well received by peer reviewers during the process of submission to science journal.

Fractional Crystallization

Fractional crystallization must be explained before defining the radiometric methods. As magma begins its long journey upward from deep in the earth, it comes in contact with cooler rock. This contact causes the magma to slowly cool. When this happens, those elements with higher melting points begin to crystallize. The density of these crystallized elements is greater than that of the surrounding liquid magma and they fall out of the upwardly mobile magma and separate from it, or fractionate. This is what is meant by fractional crystallization. This doesn't happen all at once. The upper portion of the magma is coolest, and that is where more crystallization of high melting point elements takes place.

When the magma finally breaks through the earth's crust during the eruption of a volcano, the cooler material freezes first. This material also is the most depleted of high melting point elements. Lava coming out later has greater concentrations of those same elements. This lava flows over the hardening magma and downward. The situation is a bit different for magma that never escapes the earth's crust, but it too undergoes this process of fractionation. In both cases, when a very large volume of magma lakes (remains in place) and cools to a solid, the outermost parts of the mass cool first and the high melting point substances crystallize first. In such situations, a gradient of all substances is created: the low melting point substances tend to increase in concentration toward the middle of the rock and the higher melting point substances increase in concentration toward the surface of the rock.

Independent radiometric methods verify each other

Evolutionists claim the various methods of radiometric dating do not have the same sort of problems, so when different methods result in giving the same age for a rock, that must be the rock’s true age. For example, a rock might be dated by the uranium/lead method, and then by the potassium/argon method. Argon is a gas. Because it is a gas, when magma erupts out of the earth, argon escapes because the lava is still molten. The clock is reset. One can be certain that the initial concentration of argon is zero. Therefore, the equations for solving time since formation of the rock will be accurate because no assumption has to be made about the amount of argon present when the rock first formed. If the age from potassium/argon dating and the date derived from uranium/lead dating agree, then the date must be correct. This is a case where two independent methods verify one another. We could consider situations in which other methods could be done that also would agree, but let’s consider just these two.

Fractional crystallization might cause the magma to have an artificially old date, but could this happen with the potassium/argon method? First, there is no guarantee that all the argon initially in the rock escapes while it is still molten. There are many known instances of lava flows occurring in the last few hundred years. Yet, when the flows are dated, the ages are excessive, dating several million years old.

One oil geologist, a creationist, questioned Woodmorappe's remarks, saying that radiometric dating is reliable because there are more "too young" results than "too old" results. Woodmorappe replied:

Actually, the fact that there are more "too young" values means very little, for something being "too young" or "too old" presupposes that there already is a "correct" value with which to compare all other results! That there are more "too young" than "too old" values probably only means that geochronologists have come to believe that older results tend to be accurate and hence have come to accept older results (selected from the welter of contradictory results) as being "correct." [Woodmorappe, 1985]

Gunter Faure explains that the U.S. Geological Survey used to have much younger uranium/lead ages accepted as correct. [Faure, p.282] When older dates were obtained by a different way of measuring the ratio of lead and uranium, geologists decided the older dates were correct. They had to explain away Holmes’ time scale as coming from argon-purged and strontium-purged samples, which made them too young. After all, if the argon in a sample were somehow removed, at least in part, the sample's age would appear younger since argon is the decay product of potassium (see below). This is one reason why Woodmorappe says, there is now a superabundance of too young results.

The Grand Canyon

The Grand Canyon, long touted by evolutionists as clear evidence for long geological ages, holds many surprises and contradictions for evolutionists and their theory. Vastly different dates have been derived for the top and bottom layers of Grand Canyon. Rocks dated by the isochron method by five independent laboratories consistently showed that samples taken from lava flows at the top of Grand Canyon by Institute for Creation research geologists were about one billion years older than samples taken from the basement rocks in the canyon.

The Moon

Rock samples brought back from the moon were tested and dated. Some were only millions of years old, while others were 28 billion years old. The moon is assumed to be 4-4.5 billion years old by evolutionists. The following table shows the wide age spread scientists measured in moon rocks brought back during the Apollo program. [Whitcomb]

These are the results the investigators were willing to publish. It is often the case that discordant dates are withheld, ignored, or thrown out. Then when the accepted dates are presented, the comment is "See how close these results are in agreement with previous determinations!" Of course, they are going to be in agreement. How could they be anything else when discrepant dates are thrown out? Brent Dalrymple (USGS) excluded the discrepant moon rock dates from his book Age of the Earth. He affirmed that all the dates obtained from moon rocks agreed with one another within a few million years at most.

The Koongarra Uranium Deposit

Andrew Snelling, a geologist committed to creationism, questions the validity of radiometric dating procedures designed to produce isochrons. [Snelling, 1994] Isochron dating is supposed to be the most reliable means for getting the correct age of a rock and for assuring that the age is correct. The isochron methods have a built-in checking system.

Sources of Error In The Laboratory

When scientists are dating a rock sample, Faure points out that there are several sources of laboratory error, which can greatly affect the results obtained. Let’s assume that the laboratories doing the dating have reliably overcome the obstacles and concentrate on more difficult problems in dating a rock.

If the ages of rocks measured in a laboratory do not agree with the assumed ages of the strata in which they were found (based on the index fossils), the dates are considered wrong and are usually discarded. If geologists find a rock in a Cambrian formation, its measured age must be near the 500-570 million year range, plus or minus 50 million years to be acceptable (some labs are more generous).

Faure says the most likely uncorrected laboratory error is unconfirmed lab results because the methods are time consuming, "which discourages replication of analyses and thereby results in inadequate documentation of analytical errors." [Faure, pp. 62-63]

If this is true, not many geologists spend the extra time and money to verify their results. What geologists often do if a date falls too far outside the predetermined age range, is either to discard the result or to declare the date discordant. There are established methods for deciding whether a result is discordant. Faure provides some basic guidelines for establishing "concordia" and "discordia," e.g., Uranium-Lead systems. [Faure, pp. 291-304].

Efforts are made to minimize laboratory errors, but they do crop up, and they probably crop up with greater frequency that the laboratories would like to admit. In summarizing his chapter on Uranium, Thorium-Lead methods of dating, he says that in many cases the resulting dates are discordant due to loss of Lead or Uranium.

Uranium/Lead Dating Method

Almost everyone knows that uranium decays into lead, and that it takes 4.5 billion years for half the uranium to decay. This is its half-life. The ratio of daughter to parent isotopes in a sample might represent an age relationship. If a rock contained no Lead-206 when it first formed, one can assume that the lead either came from the decay of Uranium-238 or water carried it in and deposited it in the rock. If the half-life of the parent is known and the laboratory determines the quantity of parent and daughter isotopes, they can be reliably converted into number of years.

As an example, let's suppose we have a sample and find that it has twice as much lead as it does uranium. What are the assumptions we must make about this sample? According to Faure, we must assume the following things to date something using the uranium/lead methods [Faure, pp. 287-288]:

1. "The assumed initial concentrations of the lead isotopes are correct."

Response: No one knows what the initial concentrations were. That is why they must be assumed. What one assumes is often colored by one's belief about the age of the earth.

2. "The sample tested has remained closed to uranium, thorium, lead, and all intermediate daughters throughout its history."

Response: This is an unrealistic assumption. Faure admits that in many cases the resulting dates are discordant due to loss or gain of Lead or Uranium. Uranium, radium and lead salts are soluble in water. No one knows how much of each has been transported in or out of the rocks. Radon, a gaseous daughter isotope of uranium, is constantly leaking into our homes from the rocks below. Faure says that each minute per square centimeter 42 radon atoms escape into the atmosphere [Faure, 374]. The radon escapes from the rocks geochronologists assume are closed. Obviously, the rocks are not closed. Loss of radon from rocks implies that the determined ages of rocks are too young.

Robert Gentry, a leading authority on radiohalos, crossed over into the forbidden territory of creationism after he discovered the existence of primordial polonium halos in the 1970’s and has been shunned by his peers ever since. According to Gentry, primordial polonium halos in granite and other basement rocks of the earth prove that the earth was formed instantaneously. [Gentry, 1992] Evolutionary geologists wishing to refute the origin of polonium halos argued that the polonium was transported from uranium radiocenters either by water flow through the radiocenters or by the escape of radon gas from those centers. If they are willing to admit such mobility in solid granite, they must also be willing to say that granite rocks are not closed to the migration of radioisotopes. (See the articles at Polonium Pleochroic Halos and Creation's Tiny Mysteries for further discussion on polonium halos and their significance for rapid creation of earth’s basement rocks.)

Lead’s mobility increases with increased temperature and pressure. Robert Gentry examined zircons from drill core samples and reported that the lead concentrations are essentially the same both near the surface and from great. Temperature increases with depth in the earth. At a depth of 15,000 feet, the temperature is 313° C (595° F). Both lead and helium would quickly leak out of zircons at that temperature. According to conventional geology, this material was supposed to be about 1.5 billion years old. The amount of lead and helium in the zircons should have decreased rapidly with depth because heat speeds their escape from zircons. Gentry examined drill cores of granite from New Mexico. He noticed that the amount of lead retained in zircons at 960 meters depth was the same amount found at 4310 meters (see zircon/lead table). [Gentry, 1982] Helium concentration at a depth of 9500 feet was still surprisingly high for rock that was supposed to be 1.5 billion years old.

3. "The decay constants of U-238, U-235, and Th-232 are accurately known."

Response: There is no way for us to know that this assumption is right for all time. Neutrino bursts from supernovae can accelerate the decay rate by further destabilizing the nuclei of radioactive isotopes. There is an ongoing debate whether the speed of light is slowing down. [Aardsma, Humprheys] If the speed of light is slowing down, this would slow the decay rates of radioactive materials.

4. "The uranium isotope composition is normal and unmodified by fractionation processes or natural chain reaction fission of U-235."

Response: This is probably the safest assumption, but even it must be questioned. Are we to assume that when the world first formed from interstellar debris that the uranium isotopes were consistent regardless of when the supernovae creating them exploded? Is it correct to assume that each supernova created the same mix of isotopes? May we also assume that the molten earth allowed for thorough mixing so that the isotopic ratios are consistent throughout the world? Magma flows are seldom, if ever, homogeneous. To assume the entire planet was homogeneous is wrong.

5. Analytical results are free of errors.

Response: Possibly the results are free of errors, but the assumptions used in radiometric dating always predominate in any test. It seems that "concordia" is not entirely independent of the underlying assumptions used in radiometric dating. What ratio of parent and daughter isotopes were originally present when the rock first formed? How much of each made up the material that became the earth from supernovae occurring long ago? When did those supernovae occur? There may be independent methods, but they all depend on prejudicial assumptions.

Is the first assumption valid? How accurately can the initial concentrations of parent and daughter isotopes be known? One's assumptions about the age of the earth are going to affect the assumptions made about the initial concentration of lead. If you believe the earth is very young or recently created, you will assume that most of the lead was there from the creation. If you believe the earth is billions of years old, you will assume that much of the lead wasn't there initially and is the result of uranium decay over billions of years. How old one thinks the earth is will determine which assumption is made about the initial quantity of lead. If one assumes the earth is 10 billion years old, then the assumed amount of initial lead will be less than what one will assume if it is believed the earth is only five billion years old.

We cannot assume that initially there was no lead in the earth's crust. First, it is assumed that no element heavier than lithium was formed in the Big Bang. [Silk] Early in 1992, researchers began to doubt this. Theoretically, all the elements up to and including iron can be created during the normal energy producing process of a star, which is called thermonuclear fusion (thermo = heat; nuclear = of an atom's nucleus; fusion = fusing together). It is during this process that nucleosynthesis occurs (when the nucleus of a heavier atom is synthesized by the fusion of two nuclei of lighter atoms).

If the universe did begin with a Big Bang, all the elements heavier than iron had to be created in supernova explosions, because the production of heavier elements by fusion does not release energy, as it allegedly does during the fusion process of the lighter elements. Instead, production of heavier elements requires more energy than stars can normally produce. This is why so much energy is released when atoms of uranium are split in nuclear fission: the enormous energy it took to bind that nucleus is freed [Spitzer]. After a star explodes in a supernova, creating uranium and many other elements, the radioactive decay process of uranium to lead could begin. Since evolutionists assume the universe is 13-20 billion years old, much of the initial uranium produced by dying first and second generation stars decayed into radiogenic lead long before the creation of the earth. Most of the radiogenic lead in the earth's crust was generated before the birth of our planet. (If we can detect the neutrino burst from 1987A supernova, we should be able to detect solar neutrinos. However, through decades of neutrino counting, it is clear than not enough neutrinos are being detected to prove that the sun is powered by nuclear fusion. This brings up the question of what really motivated scientists to reject Kelvin’s and Helmholtz’ suggestion that the sun was powered mainly by gravitational contraction--a process which puts an 15-30 million year upper limit on the age of the sun.)

Then over an unknown period of time (several million to several billion years--we have no way of knowing), interstellar gas and dust coalesced into the sun and planets as the result of gravitational attraction. Assuming that the universe's age is 15-20 billion years, some of the lead in the earth's crust decayed from uranium long before it became part of the earth. Uranium doesn't care where it is. It will decay in space just as readily in a rock or a star. This long period of interstellar residency would see the extinction of short and medium-lived isotopes, such as polonium since they would decay to lead long before reaching the earth.

Joseph Silk and other astronomers think our sun is a third generation star: the product of the Big Bang and two successive periods of star formation and supernovas. This means the uranium decay actually began 10-15 billion years ago, depending how old the universe is and if the universe began by a Big Bang. This uranium decay would result in the production of more lead in the universe than there is uranium. If uranium has a half-life of 4.5 billion years, the universe is two or three U-238 half-lives old, so there should be much more lead than uranium. There are so many unknowns at this point, to make an assumption about the initial lead in the earth's crust simply reveals one's philosophical bias. But now we can ask how much Lead-206 and U-238 are there?

The second assumption Faure says we must make is that the sample tested has remained closed to uranium, thorium, lead, and all intermediate daughters throughout its history. There is not even a remote possibility that this is true. Uranium salts are soluble in water containing dissolved oxygen under pressure. These salts migrate readily, both on the surface and underground. The radioactive substances in granite are found mainly on the grain surfaces of the rock crystals. This is in accordance with the principle of fractional crystallization, which is discussed later in the chapter.

Some suppose that a diligent and careful statistical analysis of the dates obtained from numerous rock samples will define a mean into which the vast majority of dates will fall. This is naive thinking, as the next section on age inconsistencies shows. How old can we say the moon is when a dozen samples ranging from millions of years to 28 billion years are recorded?

Most uniformitarians assume that the fossil record indicates several billion years of geological history.

Potassium-Argon Dating

Faure wrote,

The conventional K-Ar method of dating depends on the assumption that the sample contained no argon at the time of its formation and that subsequently all radiogenic argon produced within it was quantitatively retained. Because argon may be lost by diffusion even at temperatures well below the melting point, K-Ar dates represent the time elapsed since cooling to temperatures at which diffusion of argon is insignificant [Faure, p. 93].

Potassium decays to a gas called argon. Faure begins his discussion by saying that it is assumed that the sample submitted for analysis had no radiogenic argon immediately after complete crystallization of the rock, because all argon outgassed prior to solidification. That is only one assumption that is made during the dating process. That assumption is not correct. Each dating scheme has it's own set of assumptions and problems associated with it, but for the sake of brevity, I will concentrate only on the K-Ar method.

In his chapter on K-Ar dating, Faure says the following additional assumptions must be made:

1. No radiogenic Ar-40 produced by decay of K-40 in the mineral during its life time has escaped.

Response: Gaseous argon can easily escape wherever microfractures exist in rock. This relates to a very complicated argument Robert Gentry put forth in the scientific literature starting around 1967. Gentry was made a visiting scientist position at the Oak Ridge National Laboratory and given grants by the National Science Foundations. During his tenure there, he made an important discovery that had far reaching ramifications in the creation/evolution debate. A few opponents of Gentry claimed that polonium halos resulted from the removal of uranium daughter products from uranium radiocenters via water flow through microfissures in granitic rocks or by the flow of gaseous radon, a daughter product of uranium decay which decays into polonium. According to them, this is why it appears that the polonium was not associated with uranium radiocenters. Both of these explanations could not convincingly account for the focused halos resulting from discrete point sources of polonium, since these methods of transport would have caused smearing of the halos as some of the polonium atoms decayed in transit. This is because the half-life of Po-218 is only 3.05 minutes, and the half-life of Po-214 is 164 microseconds. The halos result from alpha particle damage to the crystal lattice of the surrounding rock as the polonium decays. It takes approximately 100 million atoms to produce the spherical halos in the biotite crystals surrounding the radiocenters. The brunt of Gentry's hypothesis was that if the earth was molten at some time in its history, how could there be any polonium halos independent of uranium radiocenters? Even if the entire universe had consisted of polonium-218, about six hours later all of it would be Po-210, lead, and helium. The granite could never have been molten, otherwise the Po-218 halos would have been wiped out because it takes far more than six hours for molten granite to cool to a solid. As it turned out concerning Gentry's findings, it was not the criticism by evolutionists that brought about the demise of Gentry's claim that granite was the original creation rock. Rather, creationists, knowing that sedimentary rock generated on day three of the creation week would be void of fossils. If sedimentary rocks containing fossils were found containing granite intrusions from granitic magma, Gentry's claim for granite would be repudiated. This is because fossil-bearing (fossiliferous) sedimentary rocks had to be formed after life was created. I was saddened to see Gentry's hypothesis refuted. Maybe Gentry's hypothesis can be salvaged. Perhaps the fossiliferous sediment has not been intruded by the granite. Instead, what happened is that the Flood water deposits were conformably deposited around denuded granite. One aspect that needs to be thoroughly research is whether the granite is intrusive or overlaid.

2. The mineral became closed to Ar-40 soon after its formation, which means that it must have cooled rapidly after crystallization, unless it formed at a low temperature.
3. No Ar-40 was incorporated into the mineral either at the time of its formation or during a later metamorphic event.
4. An appropriate correction is made for the presence of atmospheric Ar-40.
5. The mineral was closed to potassium throughout its lifetime.
6. The isotopic composition of potassium in the mineral is normal and was not changed by fractionation or other process, except by decay of K-40.
7. The decay constants of K-40 are known accurately and have not been affected by the physical or chemical conditions of the environment in which the potassium has existed since it was incorporated into the Earth.
8. The concentration of Ar-40 and of potassium were determined accurately [Faure, p. 67].

He says that these assumptions require careful evaluation in each case and place certain restrictions on the geological interpretation of K-Ar dates. He says that the last two assumptions are quite general in scope and express certain fundamental conditions of dating by any method based on radioactivity. The isotopic composition of potassium in natural samples is believed to be constant, even though fractionation of potassium isotopes has been observed on a small scale across contacts of igneous intrusion.

A correction needs to be on this point. Fractional crystallization can greatly vary the isotopic composition in any igneous formation, even potassium, as Faure says [Faure, p. 68]. For example, Tarbuck and Lutgens mention that feldspar crystals will have calcium-rich interiors surrounded by zones that are progressively richer in sodium, especially if the rate of cooling occurs rapidly enough to prohibit the complete transformation [Tarbuck]. This must be true of rocks of all composition, in accordance with the Bowen's reaction. Denial of this would render the doctrine of fractional crystallization meaningless.

Ways argon can be lost from a rock before dating [Faure, p. 69]:

1. Inability of a mineral lattice to retain argon even at low temperature and atmospheric pressure.
2. Either partial or complete melting of rocks followed by crystallization of new minerals from the resulting melt.
3. Metamorphism at elevated temperatures and pressures resulting in complete or partial argon loss depending on the temperature and duration of the event.
4. Increase in temperature due to deep burial or contact metamorphism causing argon loss from most minerals without producing any other physical or chemical changes in the rock.
5. Chemical weathering and alteration by aqueous fluids leading not only to argon loss but also to changes in the potassium content of minerals.
6. Solution and redeposition of water-soluble minerals, such as sylvite.
7. Mechanical breakdown of minerals, radiation damage, and shock waves. Even excessive grinding during preparation of sample for dating by the K-Ar method may cause argon loss.

Faure outlines further problems with the K-Ar dating method [Faure, p. 72]:

1. Addition of non-radiogenic argon to sample prior to testing.
2. Argon that was dissolved in the magma and that may have originated from the mantle of the Earth or by outgassing of old K-bearing minerals of the crust.
3. Argon that was evolved during later thermal metamorphism of the rocks and that diffused into the minerals during that event.
4. Atmospheric argon adsorbed on grain boundaries and microfractures while the rock was exposed to the atmosphere in the field and in the laboratory or firmly held within the crystal lattice.

There are many other problems associated with the K-Ar dating method, but the above gives one an idea of great the problems are. Presently, there is far more Ar-40 than the decay of K-40 could have produced in 4.5 billion years.

Repudiation of the Rb-87/Sr-86 Isochron Dating Method

What could the initial concentration of Strontium-87 (Sr-87) have been? There is more than ten times as much Sr-87 than could have been produced by rubidium-87 (87Rb) decay over five billion years.

The Isochron Method - what is it?

Gunter Faure says that fractional crystallization of magma and separation of crystals from the remaining liquid result in the formation of suites of comagmatic igneous rocks of differing chemical composition (and I say for the reasons I just gave above--and a few more!). All the rock specimens taken from this magma suite, when tested for their concentrations of strontium (Sr) and rubidium (Rb) and plotted on a graph, will plot as points on a straight line in the x,y coordinates, where x is the ratio of 87Rb/Sr-86 and y is the ratio of Sr-87/Sr-86.

This straight line is called an "isochron" because each point represents the various parts of the rock that cooled essentially at the same time and therefore have the same age. Faure says that it must be assumed that all the diverse rocks that formed from the magma had the same initial strontium 87/86 ratios (which may or may not be true). This gets rid of the problem of fractional crystallization, and the age of the rock can be calculated.

It is assumed that the rock from which the samples were taken did not have a loss or gain of daughter and parent isotopes after crystallization. Noticeable deviations from the isochron are probably a reflection of outside contamination or loss of isotopes through one or another means.

The isochron dating method is popular with geochronologists because it is not necessary to know the initial concentrations of parent and daughter isotopes. The assumptions that are made are:

1. The rock was a closed system (no gain or loss over time)
2. The daughter isotope was isotopically homogeneous throughout the magma prior to crystallization.
3. The samples of rock represent the rock unit that was formed at the same time.
4. Decay rates have not changed with time. Some scientists have actually been able to change the decay rates by external influence. (During the period 1949 to 1972, changes in decay rates were produced by changes in pressure, temperature, chemical state, electric potential, stress of monomolecular layers, destabilization by neutrino sea, etc. [Dudley 1976, Dudley 1972].

Problems with isochron dating

Y.F. Zheng at the Geochemical Institute (University of Gottingen, Germany) made the following observations:

The Rb-Sr isochron method has been one of the most important approaches in isotopic geochronology. But some of the basic assumptions of the method are being questioned at the present time. As first developed the method assumed a system to have: (1) the same age; (2) the same initial Sr-87/Sr-86 ratio; and (3) acted as a closed system. Meanwhile, the goodness of fit of experimental data points in a plot of Sr-87/Sr-86 vs. 87Rb/Sr-86 served as a check of these assumptions. However, as the method was gradually applied to a large range of geological problems, it soon became apparent that a linear relationship between Sr-87/Sr-86 and 87Rb/Sr-86 ratios could sometimes yield an anomalous isochron which had no distinct geological meaning. A number of anomalous isochrons have been reported in the literature and various terms have been invented, such as apparent isochron, secondary isochron, inherited isochron, source isochron, erupted isochron, mixing line, and mixing isochron. Even a suite of samples, which do not have identical ages and initial Sr-87/Sr-86 ratios, can be fitted to isochrons, such as aerial isochrons. [Zheng]

On page 2 of his paper he wrote:

"Evidently the theoretical basis of the classical Rb-Sr isochron is being challenged and some limitations of its basic assumptions are being revealed....Some of what this paper contains is not new to isotopic geochronologists, but it is drawn together here for the first time and is placed in a context within unifying general models for Rb-Sr dating."

Changes in the initial concentrations of Rb and Sr are possible. Flow of hot water through the rock is one of several important means, as Zheng admits:

"In some cases, gain or loss of Rb and Sr from the rocks is so regular that a linear array can be produced on the conventional isochron diagram and a biased isochron results from the altered rocks to give spurious age and initial Sr-87/Sr-86 estimates," [Zheng, p. 13]

At the beginning of his paper, he wrote:

As it is impossible to distinguish a valid isochron from an apparent isochron in the light of Rb-Sr isotopic data alone, caution must be taken in explaining the Rb-Sr isochron age of any geological system.

He equally applies the problem to the uranium-lead (U-Pb) and the in vogue samarium-neodymium (Sm-Nd) isochron methods. He concludes his paper with:

"In conclusion, some of the basic assumptions of the conventional Rb-Sr isochron method have to be modified and an observed isochron does not certainly define a valid age information for a geological system, even if a goodness of fit of the experimental data points is obtained in plotting Sr-87/Sr-86 vs. 87Rb/Sr-86. This problem cannot be overlooked, especially in evaluating the numerical time scale. Similar questions can also arise in applying the Sm-Nd and U-Pb isochron methods."

Non-radioactive geochronometers

Henry Morris published a long list of geochronometers [Morris], regular, clock-like processes by which the age of the earth might be measured. These processes are unknown, ignored, or unjustifiably spurned by evolutionists simply because they provide ages too short to allow for evolution.

Salt Influx in the ocean

The common salt (NaCl) content of the oceans increases all the time. Every year rain, snow, and groundwater flow dissolves a certain amount of salt and transports it to the oceans by rivers and streams. If one assumes that about the same amount of salt is carried to the ocean each year, the time it would take to bring the oceans to their present saltiness if initially they had been fresh water would be about 62 million years [Austin]. This does not mean the earth is 62 million years old, but it does place an upper limit on the age of the oceans. Because sodium chloride is so soluble in water, it is easily dissolved out of the soil and rocks. There is no mechanism that returns salt to the land in quantities remotely comparable to the amount entering the oceans.

Evolutionists responding to this paper insist that sodium is absorbed into the sediments. Some of this does occur, but is it reasonable to assume that the huge quantities of sodium accumulated in the oceans for more than 4 billion years are removed in this way? Recycling of sodium on this scale would require ocean sediments to be subducted under the continents, melted and redistributed at or near the surface of the continents as basalts. Recycling of sodium by this means would imply that most continental crust would have to consist of basalt instead of granite.

Radiometric dating methods, as you have seen, are not so straight forward or cut and dried as geochronologists would like us (John Q. Public) to believe. There are other geochronometers (age clocks) that show the earth is very young. Henry Morris' book, The Biblical Basis for Modern Science, lists 68 geochronometers showing the earth to be young, such as,

1. The amount of helium in the atmosphere is too little if the earth is 4.5 billion years old. The helium concentration in the atmosphere can be produced in less than 10,000 years, and not much escapes into space as evolutionists argue. Helium is produced by the decay of uranium, thorium, radium, radon, polonium-210, -214, and -218. Larry Vardiman, a nuclear physicist at the Institute for Creation Research, has written an excellent monograph, The Age of the Earth's Atmosphere. In it he explains why the earth cannot be 4.5 billion years old based on the low level of helium in the atmosphere.
2. The concentration of sodium salt in the oceans is far too low based on the measured annual input from rivers. Based on present rates of sodium input into the ocean and its concentration in the ocean, the earth can be only 62 million years old. Why isn't there more salt in the ocean if the earth is billions of years old?
3. The amount of dust in the solar system vs. the Poynting-Robertson Effect. This effect caused dust to fall into the sun or onto a planet. The smaller the dust particle, the greater the Poynting-Roberton effect will be, and the faster it will fall. The solar system is far too dusty to be so old as evolutionists claim. After 170 million years, dust particles one centimeter in radius and smaller would have been drawn into the sun out to a distance three times greater than from the sun to the earth, but there are still enormous numbers in this size range striking the earth's atmosphere daily.
4. The temperature of the earth is too high for a planet 4.5 billion years old. Based on known concentrations of radioactive material in the earth and the heat generated from their decay, which slows down the cooling process, the earth cannot be much more than 100 million years old. Dr. Harold Slusher, a geophysicist and professor of nuclear physics at the University of Texas at El Paso has written a very rigorous, mathematical study on this entitled Age of the Earth.

Of course, evolutionary geochronologists reject these things, because they show the earth to be young. A person's philosophical bias determines which are acceptable geochronometers. It has nothing to do with the reasonableness of the method.

Bibliography and Footnotes

Aardsma, G. E., "Has the Speed of Light Decayed Recently?—Paper 1," Creation Research Society Quarterly, 25:36-40, 1988.

Arculus, Richard, "Uranium: supernova to super nuclear," This article is based on a paper he presented at the Uranium Institute Mid-Term Meeting in Adelaide on 17 April 1996.

Austin, S. A., and Humphreys, D. R., "The Sea’s Missing Salt: a dilemma for evolutionists," in Proceedings of the Second International Conference on Creationism, edited by R. E. Walsh and C. L. Brooks, pp. 17-33, (1990).

Burchfield, J. D., Lord Kelvin and the Age of the Earth, Science History Publications, New York, p. 110, (1975)

Butcher, H. R., 1987, "Thorium in G-dwarf Stars as a Chronometer for the Galaxy," Nature 328:127

Cowen, R., "Found: Primeval Galaxies," Science News, 149:120-127, Feb 24, (1996).

Dudley, H.C., "Phenomenological Causal Model of Nuclear Decay, Assuming Interaction with Neutrino Sea," Lettere Al Nuovo, Cimento, Vol. 5, No.3, p. 232, (9/16/72).

Dudley, H. C., The Morality of Nuclear Planning, Glassboro, pp. 52-57 (1976).

Faure, Gunter, Principles of Isotope Geology, 2nd ed., John Wiley & Sons, New York, (1986).

Gentry, R. V., "Differential Lead Retention in Zircons: Implications for Nuclear Waste Containment," Science 216:296-298, (1982).

Gentry, R. V., Creation’s Tiny Mystery, Earth Science Associates, Knoxville, (1992).

Humphreys, D. R., "Has the Speed of Light Decayed Recently?—Paper 2," Creation Research Society Quarterly, 25:40-45, (1988).

"Mantle, Geochemistry: Probing the Source of the Earth's Crust," Science, 203:530, 1979.

Morris, Henry M., The Biblical Basis for Modern Science, Baker Book House, Grand Rapids, p. 478, (1984).

Pilkey, O.H., "Mathematical modeling of beach behavior," GSA Today, pp. 11-12, (May 1996).

Silk, Joseph, The Big Bang, Revised and Updated, W.H. Freeman and Company, New York p. 148, (1989).

Slusher, Harold, Gamwell, Thomas, The Age of the Earth, Institute for Creation Research, El Cajon, (1978).

Snelling, Andrew, "U-Th-Pb dating: an example of false isochrons," in Proceedings of the Third International Conference on Creationism, edited by R. E. Walsh, pp. 497-504, (1994).

Spitzer, Jr., Lyman, Searching Between the Stars, Yale University Press, New Haven, p. 17-19, (1982).

Tarbuck, E., F. Lutgens, The Earth: An Introduction to Physical Geology, 2nd ed., Merrill Publishing, pp. 55-57, (1987)

Whitcomb, J. C., DeYoung, D. B., The Moon: Its Creation, Form and Significance, BMH Books, Winona Lake, p. 100, (1978). The table data was taken from the following sources:

• Proceedings of the Second Lunar Science Conference, Vol. 2, pp. 1117, 1494, 1496, 1499, 1516, 1539, 1593, 1620, 1631 (1971).
• Apollo 12 Preliminary Science Report (NASA SP-235), pp. 205-208 (1970).
• Science, 167, 3918, pp. 462-463, 471-473, 479-480, 555-558 (1970).
• Earth and Planetary Science Letters, 14, 281 (1972)
• Proceedings of the Third Lunar Science Conference, Vol. 2, 1550 (1972)
• Proceedings of the Fourth Lunar Science Conference, Vol. 2, pp. 1200 and 1804 (1973).
• Earth and Planetary Science Letters, pp. 17, 36 (1972).

Woodmorappe, John, "Radiometric Geochronology Reappraised," Creation Research Society Quarterly, 16(2):102-148, (1979).

Woodmorappe, John, "Some Additional Comments Concerning Several Matters (Part I)," Creation Research Society Quarterly, 21(4):209, (1985).

Zheng, Y.F., "Influences of the nature of the initial Rb-Sr system on isochron validity," Chemical Geology (Isotope Geoscience Section), vol. 80, pp. 1-16, 1989.