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Our first four segments on radiometric dating have now been completed. We have covered the basics of radiometric dating, the general obstacles to igneous and metamorphic dating, the particular obstacles facing the prominent potassium-argon method, the obstacles facing the carbon-14 method, as well as the problems a global flood imposes on all these dating methods. At this point, we are nearly finished with our examination of radiometric dating. Only 2 segments remain: the minor remaining radiometric dating methods and the problems with the decay rate factor, which must be known to perform radiometric age calculations.

Our coverage of radiometric dating so far has largely focused on 2 categories of methods: methods that date igneous and metamorphic rocks, which provide the timescale from 100,000 to 4.5 billion years ago and carbon-14 dating, which dates once-living items and sedimentary rock and provides the timescale from the present back to 50,000 years ago. However, there are a few radiometric dating methods that do not fit into either of these categories for reasons that will become apparent below. For the most part, these are minor methods with very limited application. And it is these methods that we will address in this segment. Specifically, there are 3 remaining methods fission-track dating, uranium-series dating including radon, and rhenium-osmium dating. For the sake of simplicity, we will discuss rhenium-osmium first, since its status is the easiest to establish and can be addressed quite briefly.

The rhenium-osmium dating method is simply not used. As indicated by the quote below, at best it has only limited potential for isotopic dating.

“Dating, Absolute dating, Major methods of isotopic dating, Rhenium–osmium method – The decay scheme in which rhenium-187 is transformed to osmium-187 shows promise as a means of studying mantle–crust evolution but has displayed only limited potential for isotopic dating. Technical difficulties have yet to be overcome. Osmium is strongly concentrated in the mantle and extremely depleted in the crust, so that crustal osmium must have exceedingly high radiogenic-to-stable ratios while the mantle values are low. In fact, crustal levels are so low that they are extremely difficult to measure with current technology.” – Encyclopaedia Britannica 2004 Deluxe Edition

The fundamental problem preventing rhenium-osmium dating from being used is the fact that the daughter isotope, osmium, is “extremely depleted in the crust.” The result is that the parent-to-daughter ratios of rhenium to osmium are “so low” in crustal rock that current technology cannot measure them. And this makes radiometric dating with the rhenium-osmium pair impossible at the present time.

The next method to be discussed is fission-track dating. Fission-track dating is important because it covers the intervening gap that is not covered by either carbon-14 or potassium-argon, the 2 most prominent methods for constructing the evolutionary timescale.

“Prehistoric People, Placing prehistoric people in time – By measuring the amount of each isotope in a fossil, scientists can determine how long the decay has been going on and therefore how old the fossil is. The most commonly used dating methods of this type are radiocarbon dating and potassium-argon dating.” – Worldbook, Contributor: Alan E. Mann, Ph.D., Professor of Anthropology, Princeton University.

“Geologic Time, III DATING METHODS – The two radioactive decay sequences most useful to geologists are the decay of carbon-14 into nitrogen-14 and the decay of potassium-40 into argon-40. Carbon-14, or radiocarbon, dating works for organic materials less than about 50,000 years old…Geologists can use potassium-argon dating to determine ages of rocks from about 100,000 years old to as old as the earth itself.” – "Geologic Time," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

“Dating Methods, III ABSOLUTE DATING METHODS. E Radiometric Dating, E7 Fission-Track Dating – The method works best for micas, tektites, and meteorites. It has been used to help date the period from about 40,000 to 1 million years ago, an interval not covered by carbon-14 or potassium-argon methods.” – "Dating Methods," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

Fission-track dating is primarily used to date micas and tektites, which are igneous and metamorphic rocks.

“Mica, Origin and occurrence – Micas may originate as the result of diverse processes under several different conditions. Their occurrences, listed below, include crystallization from consolidating magmas, deposition by fluids derived from or directly associated with magmatic activities, deposition by fluids circulating during both contact and regional metamorphism, and formation as the result of alteration processes—perhaps even those caused by weathering—that involve minerals such as feldspars…The common rock-forming micas are distributed widely. The more important occurrences follow: Biotite occurs in many igneous rocks (e.g., granites and granodiorites), is common in many pegmatite masses, and constitutes one of the chief components of many metamorphic rocks (e.g., gneisses, schists, and hornfelses). It alters rather easily during chemical weathering and thus is rare in sediments and sedimentary rocks.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Tektite – any of a class of small, natural glassy objects that are found only in certain areas of the Earth's surface. The term is derived fromthe Greek word tēktos, meaning “melted,” or “molten.” Tektites have been the subject of intense scientific scrutiny throughout much of the 20th century owing to their unknown and possibly extraterrestrial origins, but they are now recognized as having formed from the melting and rapid cooling of terrestrial rocks that have been vaporized by the high-energy impacts of large meteorites, comets, or asteroids upon the surface of the Earth. The extremely high temperatures and enormous pressures generated by such impacts melted the rocks at the site, producing clouds of molten silicate droplets that quickly cooled to a glassy form before falling back to Earth.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Metamorphic rock – any of a class of rocks that result from the alteration of preexisting rocks in response to changing environmental conditions, such as variations in temperature, pressure, and mechanical stress, and the addition or subtraction of chemical components. The preexisting rocks may be igneous, sedimentary, or othermetamorphic rocks.” – Encyclopaedia Britannica 2004 Deluxe Edition

Consequently, because micas and tektites are igneous and metamorphic rocks, fission-track dating suffers from the same debilitating reheating and migration problems that inhibit all forms of igneous and metamorphic rock dating, as we discussed in detailed earlier. In fact, fission-track dating is “highly sensitive to temperatures.”

“Dating, Absolute dating, Major methods of isotopic dating, Fission-track dating –

The preservation of crystal damage (i.e., the retention of fission tracks) is highly sensitive to temperature and varies from mineral to mineral. The technique can be used to determine mild thermal events as low as 100° C. Alternately, primary ages can be calculated if the rock was formed at the surface and cooled quickly.” – Encyclopaedia Britannica 2004 Deluxe Edition

Since heating events are deemed to cause falsely “young” ages in fission-track dating, unexpected “young” dates can be “corrected” and adjusted to get an “older” date by removing problematic portions of the sample.

“Dating, Absolute dating, Major methods of isotopic dating, Fission-track dating –

A special feature of fission-track dating lies in its ability to map the uranium distribution within mineral grains. In a uranium map for single zircon grains, the outer zones that grew during a major melting event contained much more uranium than the grains originally present. The uranium–lead age was highly biased toward the younger event and the primary age could be determined only after the outer zones were removed.” – Encyclopaedia Britannica 2004 Deluxe Edition

Thus, fission-track dating is not based upon fixed, observable evidence but upon assumed and adjustable numeric values that can change dates that are too young into dates that fit the older, expected evolutionary ages. However, since fission-track dating suffers from some additional problems beyond the assumptions and adjustments caused by reheating and migration, we will take the time to focus on fission-track dating itself. Not only is fission-track dating nullified if the rocks have been subjected to high temperatures, but fission-track dating is also nullified if the rocks have been exposed to cosmic-ray bombardment.

“Dating Methods, III ABSOLUTE DATING METHODS. E Radiometric Dating, E7 Fission-Track Dating – Rocks subjected to high temperatures or exposed to cosmic-ray bombardment at the earth's surface, however, may yield erroneous ages.” – "Dating Methods," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

Further problems with fission-track dating stem from the process of fission-track dating itself. Unlike other radiometric dating methods, fission-track dating does not utilize measurements or comparisons of parent-to-daughter ratios. Instead, fission-track dating focuses on “tracks” or “trails” left in crystals by the “spontaneous” breakdown of uranium 238 “into two fragments of similar mass.” This breakdown cracks the crystal and after being enlarged by “an etching solution” or “strong acid,” these cracks can be seen by powerful microscopes. Most importantly, the uranium quantity is measured by bombarding the sample with neutrons in a nuclear reactor. As stated in the quotes below, a nuclear reactor is used to “induce” the creation of new “fission-tracks.” And finally, the age is calculated by comparing the number of cracks produced artificially in the reactor by uranium-235 with the number of cracks produced naturally by uranium-238.

“Dating, Absolute dating, Major methods of isotopic dating, Fission-track dating – This is a special type of dating method that makes use of a microscope rather than a mass spectrometer, and capitalizes on damaged zones, or tracks, created in crystals during the spontaneous fission of uranium-238. In this unique type of radioactive decay, the nucleus of a single parent uranium atom splits into two fragments of similar mass with such force that a trail of crystal damage is left in the mineral. Immersing the sample in an etching solution of strong acid or base enlarges the fission tracks into tube-shaped holes large enough to be seen under a high-powered microscope. The number of tracks present can be used to calculate the age of the sample if the uranium content is known. Fortunately the uranium content of precisely the spot under scrutiny can be obtained by a similar process when working with a polished crystal surface. The sample is bombarded with slow (thermal) neutrons in a nuclear reactor, resulting in induced fission of uranium-235 (as opposed to spontaneous fission of uranium-238). The fission tracks produced by this process are recorded by a thin plastic film placed against the surface of the sample. The uranium content of the material can then be calculated so long as the neutron dose is known. The age of the sample is obtained using the equation, age = N × D s/D i × 6 × [10 to the power of 8], in which N is the total neutron dose expressed as neutrons per square centimetre and D s is the observed track density for spontaneous fission while D i is that for induced fission.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Dating Methods, III ABSOLUTE DATING METHODS. E Radiometric Dating, E7 Fission-Track Dating – The fission-track method, also known as spontaneous fission-track dating, involves the paths, or tracks, of radiation damage made by nuclear particles in a mineral or glass by the spontaneous fission of uranium-238 impurities. Age in years is calculated by determining the ratio of spontaneous fission-track density to that of induced fission tracks.” – "Dating Methods," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

The most significant problem with this process surrounds the subjection of the sample to a nuclear reactor in order to induce fission. As mentioned earlier in our focus on potassium-argon dating, Encyclopedia Britannica states that we can be confident that decay rates are known, reliable, and constant because decay processes take place “within the atomic nucleus.” In short, decay rates are constant because they are governed by processes that occur in a location that is isolated from the influence of an “external forces.” Consequently, it is the fact that decay processes are isolated from change that guarantees decay rates remain constant.

“Dating, Absolute dating, Principles of isotopic dating, Potassium–argon methods – The results show that there is no known process that can alter the rate of radioactive decay. By way of explanation it can be noted that since the cause of the process lies deep within the atomic nucleus, external forces such as extreme heat and pressure have no effect. The same is true regarding gravitational, magnetic, and electric fields, as well as the chemical state in which the atom resides. In short, the process of radioactive decay is immutable under all known conditions. Although it is impossible to predict when a particular atom will change, given a sufficient number of atoms, the rate of their decay is found to be constant. The situation is analogous to the death rate among human populations insured by an insurance company. Even though it is impossible to predict when a given policyholder will die, the company can count on paying off a certain number of beneficiaries every month. The recognition that the rate of decay of any radioactive parent atom is proportional to the number of atoms (N) of the parent remaining at any time gives rise to the following expression.” – Encyclopaedia Britannica 2004 Deluxe Edition

However, a nuclear reactor is clearly able to affect the processes occurring in the atomic nucleus. In fact, as we have seen concerning fission-track dating, the nuclear reacter is precisely being used to affect the atomic nucleus and induce fission. Furthermore, as we have also already seen, carbon-14 is created by the interaction of neutrons with normal carbon in earth’s atmosphere. Likewise, fission-track dating is using the nuclear reactor to “bombard” the sample “with slow (thermal) neutrons.” Clearly the measurement process used in fission-track dating actually involves elements that are capable of affecting and creating the very phenomena that the process is designed to detect.

Moreover, fission-track dating is also susceptible to errors resulting from: uneven distributions of uranium (which affects the ability to count the uranium content), statistical errors in counting cracks, and “inaccurate estimates” regarding the dose of neutron bombardment (which is also necessary to count the uranium content and to use the number of cracks for dating purposes).

“Dating, Absolute dating, Major methods of isotopic dating, Fission-track dating –

It might also be noted that uncertainties in results may arise from an uneven distribution of uranium, statistical errors in counting, and inaccurate estimates of neutron flux (dose of neutrons).” – Encyclopaedia Britannica 2004 Deluxe Edition

Effectively, every critical step of this method is prone to problems that result in erroneous ages. Due to all of these problems, fission-track dating has largely been abandoned as a means of actually calculating the age of a rock. Instead, it is used only for dating heating and cooling events.

“Dating, Absolute dating, Major methods of isotopic dating, Fission-track dating – In practice, fission-track dates are regarded as cooling ages unless proved otherwise.” – Encyclopaedia Britannica 2004 Deluxe Edition

In conclusion, potassium-argon and carbon-14 dating methods fail to work, resulting in the loss of the evolutionary timescale from the present to 50,000 years ago and from 100,000 years ago to the foundation of the earth. And, since fission-track dating is nullified by reheating and migration events, by cosmic-ray bombardment, by assumed and adjustable numeric values that can change young ages into old ages, and by a measuring process that can actually create the very decay activity it is trying to measure, the evolutionary timescale also loses the intervening period of 40,000 to 1 million years provided by fission-track dating. As the radiometric dating methods continue to crumble, not just from circular reasoning, but from problems inherent to the individual methods themselves, we arrive at one last isotope series used in radiometric dating, the uranium-series.

Uranium-series disequilibrium dating is the only radiometric dating method that we have not covered. We will begin by examining the basic concepts of uranium-series dating.

First, due to the short half-lives of some of the isotopes involved, this method is used to date relatively young items.

“Dating, Absolute dating, Major methods of isotopic dating, Uranium-series disequilibrium dating – The isotopic dating methods discussed so far are all based on long-lived radioactive isotopes that have survived since the elements were created or on short-lived isotopes that were recently produced by cosmic-ray bombardment. The long-lived isotopes are difficult to use on young rocks because the extremely small amounts of daughter isotopes present are difficult to measure. A third source of radioactive isotopes is provided by the uranium- and thorium-decay chains. As noted in Table 3, these uranium–thorium series radioisotopes, like the cosmogenic isotopes, have short half-lives and are thus suitable for dating geologically young materials.” – Encyclopaedia Britannica 2004 Deluxe Edition

This dating method is known as “uranium-series” dating instead of being known by the parent and daughter elements because uranium breaks down to lead in a series of steps becoming several different elements along the way. Thus, because numerous daughter elements are produced along the decay chain, these dating procedures are named according to their decay relationship to the parent isotope uranium.

"Dating Methods, III ABSOLUTE DATING METHODS. E Radiometric Dating, E1 Basic Theory – Radioactive elements such as uranium (U) and thorium (Th) decay naturally to form different elements or isotopes of the same element…A number of isotopes decay to a stable product, a so-called daughter isotope, in a single step (for example, carbon-14), whereas other series involve many steps before a stable isotope is formed. Multistep radioactive decay series include, for example, the uranium-235, uranium-238, and thorium-232 families. If a daughter isotope is stable, it accumulates until the parent isotope has completely decayed. If a daughter isotope is also radioactive, however, equilibrium is reached when the daughter decays as fast as it is formed.” – "Dating Methods," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

“Dating, Absolute dating, Major methods of isotopic dating, Uranium-series disequilibrium dating – The decay of uranium to lead is not achieved by a single step but rather involves a whole series of different elements, each with its own unique set of chemical properties.” – Encyclopaedia Britannica 2004 Deluxe Edition

As indicated by the first quote above, the duration of time that decay has been occurring is measued by the quantity of each element in the decay chain. The ratio of the parent isotope and all the daughter isotopes indicates how long decay has been occurring and, therefore, the age of the item.

In addition, there are 2 general decay chains used for dating purposes, the radon to lead decay chain and the uranium to thorium decay chain. As such, uranium-series dating is really a grouping of 2 dating methods involving closely-related isotopes. Because the issues involved are simpler and can be described more briefly, first we will discuss the dating method involving the decay of radon to lead. This dating method is specifically known as “Lead-210 dating.”

Radon is “a member” of the uranium to lead decay chain. However, radon is a gas. Consequently, in nature radon-222 “escapes” from the ground into the atmosphere where it decays to lead-210. Lead-210 then “falls” back to the ground and becomes a part of “glacial ice” and “sedimentary materials.”

“Dating, Absolute dating, Major methods of isotopic dating, Uranium-series disequilibrium dating, Lead-210 dating – The presence of radon gas as a member of the uranium-decay scheme provides a unique method for creating disequilibrium. The gas radon-222 (222Rn) escapes from the ground and decays rapidly in the atmosphere to lead-210 (210Pb), which falls quickly to the surface where it is incorporated in glacial ice and sedimentary materials. By assuming that the present deposition rate also prevailed in the past, the age of a given sample at depth can be estimated by the residual amount of lead-210.” – Encyclopaedia Britannica 2004 Deluxe Edition

The problem with lead-210 dating method is that it is based upon standard assumptions, which at this point have been shown to be quite unreliable. In short, this dating method requires that the rate of radon escape and the subsequent deposit of lead into surface contents has remained constant throughout the past. If these rates were not constant, then greater or lesser amounts of lead would not reflect the amount of time decay has occurred or, therefore, the age of the sample.

The only basis for these calculations is this assumption of unaltered uniformitarianism. Any degree of catastrophism would affect this enough to prevent accurate dating. And, any major catastrophic events, particularly those instrumental in glacier and sediment formation, such as a global flood, would entirely nullify this dating method. As we have already established in previous segments, catastrophism is accepted even with uniformitarianism. Therefore, the assumption that lead deposition has remained uniform over time without any interference from occasional or major catastrophic events is simply invalid. Furthermore, the substantial historic and geological evidence for a global flood also demonstrates that lead deposition, sediment formation, and even glacial ice formation are not the result of uniform processes but a rapid, cataclysmic natural event. Since the foundational assumptions for lead-210 dating are not warranted or valid, the method and the ages it renders cannot be considered objective, empirical fact.

This brings us to the uranium-thorium dating methods. Uranium-thorium is itself divided into 2 versions: thorium-excess dating and thorium-deficiency dating. In both versions, thorium is the intervening daughter element that is focus of the procedure. And the term “disequilibrium” dating is often used to describe these methods because the “excess” or “deficiency” of thorium is central to the calculation of age.

In thorium-excess dating, age measurements are based upon the fact that samples contain more thorium than they should. As indicated by the second quote below, this version of uranium-thorium dating is used to date ocean-floor sediments. And, as also indicated by the quotes below, “ionium” is simply another name for the isotope thorium-230.

“Boltwood, Bertram Borden – American chemist and physicist whose work on the radioactive decay of uranium and thorium was important in the development of the theory of isotopes…He discovered ionium, now called thorium-230.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Dating, Absolute dating, Major methods of isotopic dating, Uranium-series disequilibrium dating – The insoluble nature of thorium provides for an additional disequilibrium situation that allows sedimentation rates in the modern oceans to be determined. In this case, thorium-230 in seawater, produced principally by the decay of uranium-234, is deposited preferentially in the sediment without the uranium-234 parent. This is defined as excess thorium-230 because its abundance exceeds the equilibrium amount that should be present.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Dating Methods, III ABSOLUTE DATING METHODS, E Radiometric Dating, E5 Methods Involving Thorium-230 – Thorium ratio methods are used to date older oceanic sediments beyond the range of radiocarbon techniques. Uranium in seawater eventually decays to the thorium isotope, thorium-230 (also called ionium), which is precipitated into ocean-floor sediments. Because it has been undergoing decay longer, scientists can detect a decrease in quantity in higher levels, and a time scale can be developed in this way…The ionium-thorium age method, applied to deep-sea sediments formed during the last 300,000 years, is based on the assumption that the initial ionium content of accumulating sediments has remained constant for the total section under study and is not derived from uranium decay; the age of the sample depends on this ionium excess, which decreases with time.” – "Dating Methods," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

As indicated by the quotes above the basis for dating items using thorium-excess can be described as follows. As indicated by the second quote above, thorium is produced as uranium slowly decays into insoluble thorium, which because it is not soluble then accumulates slowly in sedimentary layers. The process of sedimentation is slow because thorium is produced by the slow process of uranium decay. And, because the quantity of thorium in sedimentation is linked to uranium decay, the amount of decay and therefore the age of the sediment are also indicated by the quantity of thorium in the sediment.

Two additional items are worth noting from the last quote above. First, notice that the timeframe for uranium-thorium dating is limited to the last 300,000 or sooner. And second, notice the uranium-thorium dating is “based on the assumption that the initial ionium content of accumulating sediments has remained constant for the total section under study.” This statement is important because it assert the requirement for uranium deposition to be uniform. Conversely, non-uniform deposits will nullify dating.

Moreover, the thorium-excess method relies on comparing the quantities of 3 different isotopes: uranium-234, thorium-230 (ionium), and thorium-232.

“Absolute dating, Major methods of isotopic dating, Uranium-series disequilibrium dating, Thorium-230 dating – The insoluble nature of thorium provides for an additional disequilibrium situation that allows sedimentation rates in the modern oceans to be determined. In this case, thorium-230 in seawater, produced principally by the decay of uranium-234, is deposited preferentially in the sediment without the uranium-234 parent. This is defined as excess thorium-230 because its abundance exceeds the equilibrium amount that should be present. With time, the excess decays away and the age of any horizon in a core sample can be estimated from the observed thorium-230-to-thorium-232 ratio in the seawater-derived component of the core. Sedimentation rates between 1 and 20 millimetres per 1,000 years are commonly found with slight variations between the major ocean basins.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Ionium-thorium dating – method of establishing the time of origin of marine sediments according to the amount of ionium and thorium they contain. Because uranium compounds are soluble in seawater, while thorium compounds are quite insoluble, the thorium isotopes produced by the decay of uranium in seawater are readily precipitated and incorporated in sediments. One of these thorium isotopes, thorium-230 (also known as ionium), has a half-life of about 80,000 years, which makes it suitable for dating sediments as old as 400,000 years. Thus, the amount of ionium in sediments can be used as a rough measure of the age of sediment. Accurate dating by measurement of ionium alone requires that the rate of sedimentation of ionium be constant with time, an assumption that does not hold for many sediments; any thorium-232 present in seawater will also precipitate, and the decay of the ratio of ionium to thorium-232 can be used as a measure of time. This method does not require a constant rate of sedimentation of ionium but simply that the two isotopes are precipitated in a constant proportion.” – Encyclopaedia Britannica 2004 Deluxe Edition

Before we move on to cover the basics of thorium-deficiency dating, it is important to notice that the last quote above limits this method to 400,000 years or less. Since a previous quote denoted a limit of 300,000, it would appear that the limit is somewhere between 300,000 and 400,000 years ago.

In thorium-deficiency dating, age measurements are based upon the fact that samples contain less thorium than they should. This process is used to date fossil shells or coral.

“Dating, Absolute dating, Major methods of isotopic dating, Uranium-series disequilibrium dating – For example, an isotope of thorium is normally in equilibrium with uranium-234 but is found to be virtually absent in modern corals even though uranium-234 is present. Over a long period of time uranium-234, however, decays to thorium-230, which results in a build-up of the latter in old corals and thereby provides a precise measure of time.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Dating Methods, III ABSOLUTE DATING METHODS, E Radiometric Dating, E5 Methods Involving Thorium-230 – In the ionium-deficiency method, the age of fossil shell or coral from 10,000 to 250,000 years old is based on the growth of ionium toward equilibrium with uranium-238 and uranium-224, which entered the carbonate shortly after its formation or burial.” – "Dating Methods," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

Modern coral and fossil shells lack thorium but have uranium. The basic concept is that modern samples don’t have thorium because enough time has not elapsed for the uranium that is present to decay into thorium. In contrast, older coral and fossil shells have both thorium and uranium. Consequently, based upon an assumed constant decay rate and the ratio of uranium to thorium, an age can be determined for the samples with thorium.

Lastly, concerning the relationship between the thorium-excess and the thorium-deficiency methods, it should be noted that both methods are restricted to measuring the age of items on the ocean floor. Thorium-excess is based upon the presence of thorium in ocean floor sediments while thorium-deficiency is based upon how much less thorium there is than uranium in older shells and coral. Thus, one method measures the sediments the other method measures the fossils.

Having identified the basic concepts of both thorium-excess and thorium-deficiency dating, we are ready to discuss some of the reasons why these methods are not reliable for providing dates and ages. As indicated in the quotes above, the underlying premise of both thorium-excess and thorium-deficiency dating surrounds the question of how different sediments and different fossils came to have different amounts of thorium and uranium. The evolutionary dating method assumes that these different quantities are a result of the slow process of radioactive decay so that the age of the items is reflected in the amount of uranium or thorium decay that has occurred. Consequently, the question is whether or not this assumption is true. Is the slow process of radioactive decay directly responsible for the thorium content of the sediments and fossils? Or, is the thorium content just as likely to be the result of other factors, which themselves do not provide a measure of time? Effectivley, the uranium to thorium decay occurs but it occurs prior to its incorporation into the sediments and fossils. Thus, the amount in the sediments and fossils does not reflect the amount of decay or time.

To answer these questions, we turn to the source of the key isotopes. Uranium is the source from which the isotopes of thorium are formed through the processes of decay.

“Boltwood, Bertram Borden – American chemist and physicist whose work on the radioactive decay of uranium and thorium was important in the development of the theory of isotopes.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Dating, Absolute dating, Major methods of isotopic dating, Uranium-series disequilibrium dating – In this case, thorium-230 in seawater, produced principally by the decay of uranium-234, is deposited preferentially in the sediment without the uranium-234 parent.” – Encyclopaedia Britannica 2004 Deluxe Edition

Uranium itself dissolves in seawater. However, thorium does not dissolve in seawater.

“Ionium-thorium dating – Because uranium compounds are soluble in seawater, while thorium compounds are quite insoluble, the thorium isotopes produced by the decay of uranium in seawater are readily precipitated and incorporated in sediments.” – Encyclopaedia Britannica 2004 Deluxe Edition

The fact that modern corals are only “virtually absent” of thorium rather than completely absent of thorium indicates that some small amount of thorium is present even in modern corals.

“Dating, Absolute dating, Major methods of isotopic dating, Uranium-series disequilibrium dating – For example, an isotope of thorium is normally in equilibrium with uranium-234 but is found to be virtually absent in modern corals even though uranium-234 is present.” – Encyclopaedia Britannica 2004 Deluxe Edition

The fact that thorium is only “virtually absent” and therefore still present in modern corals is significant because the amount of thorium even in “old” corals is so small that detecting it requires highly sensitive equipment. So, while “virtually absent” may seem like there is relatively little or no thorium in modern corals, once we realize that “old” corals have so little thorium that they require special technology to detect their small quantities of thorium, “virtually absent” is shown to still be a comparable amount.

“Dating, Absolute dating, Major methods of isotopic dating, Uranium-series disequilibrium dating – Most of the studies using the intermediate daughter elements were for years carried out by means of radioactive counting techniques—i.e., the number of atoms present was estimated by the radioactivity of the sample. The introduction of highly sensitive mass spectrometers that allow the total number of atoms to be measured rather than the much smaller number that decay has resulted in a revolutionary change in the family of methods based on uranium and thorium disequilibrium.” – Encyclopaedia Britannica 2004 Deluxe Edition

Since there has not been enough time for the thorium in modern corals to have been produced by decay, that thorium must have gotten into the corals from the surrounding environment. In this case, the corals took in some thorium but they took in much more uranium since it is water-soluble while thorium is not. This indicates that the quantity of thorium in corals, whether old or modern corals, is a result of taking in thorium from the surrounding environment. And this leaves open the possibility that thorium intake might have been greater in the past than in the present, in which case the amount of thorium in old corals would no longer be a result of long durations of decay but simply of the amount of thorium originally taken in by the coral. Further support stems from the process by which fossils are formed, including the “fossil shell or coral” used in thorium-deficiency dating. As indicated by the quote below, the hard parts of organisms become fossilized when they are buried in sediments and then their original molecular composition is replaced by minerals or particles from the surrounding sediment.

“Fossil – The hard parts of organisms that become buried in sediment may be subject to a variety of other changes during their conversion to solid rock, however. Solutions may fill the interstices, or pores, of the shell or bone with calcium carbonate or other mineral salts and thus fossilize the remains, in a process known as permineralization. In other cases there may be a total replacement of the original skeletal material by other mineral matter, a process known as mineralization, or replacement.” – Encyclopaedia Britannica 2004 Deluxe Edition

Thus, if the sediment or even the surrounding water were more rich with thorium at a certain point in the past than the present, then older, fossilized shells and corals would most likely contain more thorium than modern corals, strictly as a function of the increased presence of thorium in their environment, not as a function of radioactive decay. This possibility becomes even more relevant when we consider the fact that oceans have currents to them.

“Ocean current – horizontal and vertical circulation system of ocean waters produced by gravity, wind friction, and water density variation in different parts of the ocean. The direction and form of oceanic currents is governed by a number of natural forces, including principally horizontal pressure gradient forces; forces generated by variable density of seawater, which is a product of temperature and salinity variables; the Coriolis forces, exerted by the rotating Earth on all moving objects at or near the Earth's surface; and friction, caused by winds blowing over the ocean's surface as well as the friction between different layers of water.” – Encyclopaedia Britannica 2004 Deluxe Edition

These currents are constantly churning and mixing ocean water. As stated in the quotes below, the result of this churning and mixing is that ocean waters tend to be homogeneous (of uniform composition) as a whole while locally, from place to place, there is “water of varying characteristics” such as “salinity” or salt-content and generally “a substantial variety of chemical distributions” in the oceans. For reference, the word “particulate” in the second quote below is defined by Merriam-Webster’s Collegiate Dictionary as “minute separate particles,” such as the particles of undissolved thorium in contrast to dissolved uranium.

“Ocean, Circulation of the ocean waters, General observations – The general circulation of the oceans defines the average movement of seawater, which, like the atmosphere, follows a specific pattern. Superimposed on this pattern are oscillations of tides and waves, which are not considered part of the general circulation. There also are meanders and eddies that represent temporal variations of the general circulation. The ocean circulation pattern exchanges water of varying characteristics, such as temperature and salinity, within the interconnected network of oceans and is an important part of the heat and freshwater fluxes of the global climate.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Ocean, Chemical and physical properties of seawater, Composition of seawater – The chemical composition of seawater is influenced by a wide variety of chemical transport mechanisms. Rivers add dissolved and particulate chemicals to the oceanic margins…Particulates in transit to the seafloor, as well as materials both on and within the seafloor, undergo chemical exchange with surrounding solutions. Through these local and regional chemical input and removal mechanisms, each element in the oceans tends to exhibit spatial and temporal concentration variations. Physical mixing in the oceans (thermohaline and wind-driven circulation; see below Circulation of the ocean waters) tends to homogenize the chemical composition of seawater. The opposing influences of physical mixing and of biogeochemical input and removal mechanisms result in a substantial variety of chemical distributions in the oceans.” – Encyclopaedia Britannica 2004 Deluxe Edition

Consequently, the amount of thorium and uranium in any given region of seawater can differ from place to place and from time to time as ocean current mix and move various chemicals. In turn, the chemical composition of seawater at any given time and place effects the marine life of that area and time.

“Undersea exploration, Methodology and instrumentation, Water sampling for chemical constituents – Nutrient concentration (e.g., phosphate, nitrate, silicate), the pH (acidity), and the proportion of dissolved gases are used by the ocean chemist to determine the age, origin, and movement of water masses and their effect on marine life.” – Encyclopaedia Britannica 2004 Deluxe Edition

As a result, different amounts of thorium in either fossils or sediments might indeed reflect only that the amount of uranium and thorium in a particular area was significantly greater in the past than in the present. Therefore, the differing amounts of thorium and uranium would not be the result of radioactive decay nor indicators of age, but merely the result of larger concentrations of thorium and uranium carried in ocean waters in the past. The presence of thorium in sedimentation as a result of deposit from the surrounding environment rather than from decay is implicit in the thorium-excess method, as indicated by the quote below.

Next, we will discuss what event could possibly have contributed to a dramatically different intake of thorium by sea-floor sediments, corals, and other now-fossilized sea-floor organisms in the past. However, for now, this at least demonstrates the potential for how the thorium quantity in modern corals and fossils in contrast to old corals and fossils might not be an indication of decay time or age. Thus, the thorium-deficiency would not be an indicator of age at all.

As to what could have caused thorium intake to be dramatically different in the past than in the present, the answer is the well-attested to global flood. Both uranium and thorium are contents of volcanic activity and are contained in rock formations along ocean ridges and on the ocean floor. This means that these 2 elements are part of volcanic magma eruptions. There are 2 major divisions of volcanic rock, the subalkaline and the alkaline. The subalkaline group also has 2 divisions, the tholeiitic series and the calc-alkalic series.

Rocks from both the tholeiitic series and the calc-alkalic series contain thorium and uranium, although the tholeiitic has less of these elements than the calc-alkalic.

“Igneous rock, Forms of occurrence, Distribution of igneous rocks on the Earth's surface – Two different series of rocks are found in some volcanic chains. In Japan a tholeiitic series and a calc-alkalic series sometimes erupt from the same volcano. The former is characterized by lower magnesium, potassium, nickel, chromium, uranium, and thorium and a higher iron: magnesium ratio.” – Encyclopaedia Britannica 2004 Deluxe Edition

These subalkaline groups populate volcanic activity in the northwestern U.S.

“Igneous rock, Forms of occurrence, Distribution of igneous rocks on the Earth's surface – Most of the composite volcanoes of the Cascades Range in Oregon and Washington in the northwestern United States are characteristically calc-alkalic.” – Encyclopaedia Britannica 2004 Deluxe Edition

But more important to this dating method, these subalkaline groups populate volcanic regions along oceanic ridges, ocean floors, and island chains. This fact places them in the exact location to function as the source of uranium and thorium in ocean-flood sediments and fossils.

“Igneous rock, Classification of igneous rocks, Classification of volcanic and hypabyssal rocks – The first major division is based on the alkali (soda + potash) and silica contents, which yield two groups, the subalkaline and alkaline rocks. The subalkaline rocks have two divisions based mainly on the iron content with the iron-rich group called the tholeiitic series and the iron-poor group called calc-alkalic. The former group is most commonly found along the oceanic ridges and on the ocean floor; the latter group is characteristic of the volcanic regions of the continental margins (convergent, or destructive, plate boundaries; see below Forms of occurrence: Distribution of igneous rocks on the Earth's surface). In some magmatic arcs (groups of islands arranged in a curved pattern), notably Japan, both the tholeiitic and calc-alkalic series occur.” – Encyclopaedia Britannica 2004 Deluxe Edition

In addition, these volcanoes expel material from the mantle.

“Earth, The structure and composition of the solid Earth – Large-scale deformation of the mantle results in plate tectonics at the surface and the related phenomena of earthquakes and volcanoes.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Geologic sciences, Study of the structure of the Earth, Volcanology – A few volcanoes occur within oceanic plates (e.g., along the Hawaiian chain); these are interpretedas the tracks of plumes (ascending jets of partially molten mantle material) that formed when such a plate moved overhot spots fixed in the mantle.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Volcanism – The majority of active terrestrial volcanoes (roughly 80 percent) and related phenomena occur where two lithospheric plates converge and one overrides the other, forcing it down into the mantle to be reabsorbed…A second major site of active volcanism is along the axis of the mid-ocean ridge system, where the plates move apart on both sides of the ridge, and magma wells up from the mantle, creating new ocean floor along the trailing edges ofboth plates. Virtually all of this volcanic activity occurs under water.” – Encyclopaedia Britannica 2004 Deluxe Edition

As indicated specifically by the first 2 quotes below, oceanic magma comes from the asthenosphere, which is part of the mantle.

“Igneous rock, Origin and distribution, Origin of magmas – Basaltic magmas that form the oceanic crust of the Earth are generated in the asthenosphere at a depth of about 70 kilometres. The mantle rocks located at depths from about 70 to 200 kilometres are believed to exist at temperatures slightly above their melting point, and possibly 1 or 2 percentof the rocks occur in the molten state.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Continental drift – By the late 1960s several American investigators, among them Jack E. Oliver and Bryan L. Isacks, had integrated this notion of seafloor spreading with that of drifting continents and formulated the basis of plate tectonic theory. According to the latter hypothesis, the Earth's surface, or lithosphere, is composed of a number of large, rigid plates that float on a soft (presumably partially molten) layer of the mantle known as the asthenosphere. The midocean ridges occur along some of the plate margins. Where this is the case, the lithospheric plates separate and the upwelling mantle material forms new ocean floor along the trailing edges.” – Encyclopaedia Britannica 2004 Deluxe Edition

Furthermore, it is a known fact that volcanic activity contributes to the content of seawater.

“Marine ecosystem, The marine environment, Physical and chemical properties of seawater – The physical and chemical properties of seawater vary according to latitude, depth, nearness to land, and input of fresh water. Approximately 3.5 percent of seawater is composed of dissolved compounds, while the other 96.5 percent is pure water. The chemical composition of seawater reflects such processes as erosion of rock and sediments, volcanic activity, gas exchange with the atmosphere, the metabolic and breakdownproducts of organisms, and rain.” – Encyclopaedia Britannica 2004 Deluxe Edition

Three facts plainly demonstrate that the mantle itself is the source of the oceans’ uranium and thorium content. Rock from these volcanoes is comprised of uranium and thorium. These volcanoes are emitting material from the mantle. And volcanic activity contributes to the contents of seawater.

In addition, the following facts also corroborate the presence of uranium and thorium in the mantle and in the magma that erupts during oceanic volcanic activity. First, both uranium and thorium are extremely heavy elements.

“Uranium – Uranium constitutes about two parts per million of the Earth's crust. Uranium is a dense, hard metallic element that is silvery-white in colour.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Chemical elements, Geochemical distribution of the elements, The geochemical cycle, Early history of the Earth – Uranium and thorium, for example, are very heavy elements…” – Encyclopaedia Britannica 2004 Deluxe Edition

The fact that uranium and thorium are heavy means that they should sink down toward the core.

“Chemical elements, Geochemical distribution of the elements, The geochemical cycle, Early history of the Earth – Much of the iron was reduced to the metallic state and sank to the centre to form the core, carrying with it the major part of the siderophile elements…As indicated above, the metal sank to form the core, carrying with it the major part of the siderophile elements.” – Encyclopaedia Britannica 2004 Deluxe Edition

However, these elements are also lithophiles or “oxygen-loving” and, as indicated in the quote below, “oxygen-loving” elements “provided material for the mantle and crust.” Uranium and thorium are even explicitly placed in this category of “oxygen-loving” heavy elements that do not sink toward the core. Specifically, the fact that uranium and thorium do not sink is contrasted to iron, another heavy element which does sink.

“Chemical elements, Geochemical distribution of the elements, The geochemical cycle, Early history of the Earth – Much of the iron was reduced to the metallic state and sank to the centre to form the core, carrying with it the major part of the siderophile elements. Lithophile elements, those with a greater affinity for oxygen than iron, combined as oxide compounds, mostly silicates, and provided material for the mantle and crust…Uranium and thorium, for example, are very heavy elements; nevertheless, they are concentrated in the crust, not in the core, because of their lithophile character (affinity for oxygen).” – Encyclopaedia Britannica 2004 Deluxe Edition

The combined qualities of heaviness and oxygen affinity would expectedly cause uranium and thorium to sink but not go as deep as iron. This would expectedly place them in the molten mantle, but instead, the crust seems far more enriched with these elements than the mantle. As the quotes below indicate, crustal rocks contain about 50 times as much uranium than the rest of the earth and thorium is about “three times more abundant” in the crust than uranium.

“Earth, The interior – The Earth is geochemically differentiated to a great extent. Crustal rocks contain about twice as much of the rock-forming element aluminum as does the rest of the solid Earth and nearly 50 times as much uranium.

“Thorium – (Th), radioactive chemical element of the actinide series, in Group IIIb of the periodic table, atomic number 90; it is a useful nuclear-reactor fuel… It is about half as abundant as lead and is three times more abundant than uranium in the Earth's crust.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Chemical element, Terrestrial distribution, The earth’s mantle – It is thus probable that the mantle is relatively depleted, and the crust relatively enriched, in minor and trace elements. This is certainly true for uranium and thorium, because the amount of these elements in the crust is almost sufficient to account for the total amount of heat flowing out of the Earth.” – Encyclopaedia Britannica 2004 Deluxe Edition

The relevance of these facts can be summarized as follows. A massive, literally “earth-shattering” catastrophe, such as the Flood, involves the cracking of the crust accompanied by unprecedented volcanic activity, particularly along the ocean floor. This unprecedented volume of volcanic activity expels uranium and thorium that was previously concentrated in the upper mantle into the oceans in large enough quantity to supply the crust with much of its current uranium and thorium. Thus, the thorium along the ocean floor is not strictly the product of uranium decay but already existed in the upper mantle. Once expelled, the uranium dissolves in the seawater but the thorium does not dissolve. So, the thorium settles out as part of the sedimentation. The presence of undissolved thorium would account for the burial of thorium in excessive amounts in ocean floor sediment. However, this process would indicate a massive amount of thorium was buried layer after layer in a very short time rather than being built up slowly as uranium decayed to thorium, which then gradually accumulated into sedimentary layers. Since fossils are formed as elements from the environment replace molecules in the body of the dead organism, with the large-scale inflow of thorium, we would expect to find larger amounts of thorium in corals and shells fossilized in the flood. Conversely, the removal of thorium due to the relatively quick sedimentation would further explain why modern corals and fossils since this catastrophe do not contain the same saturation of thorium as their buried ancestors who experienced this disaster.

In conclusion, neither the thorium-excess in ocean-floor sediments nor the thorium-deficiency in ocean fossils, such as shells and corals, necessarily reflects the length of time radioactive decay has been occurring or the age of ocean-floor sediments or fossils. Like the other dating methods we have examined, it is only the assumptions and not the evidence itself, which produces the long ages in these dating methods. Concerning the uranium series dating methods, we can see that there still remains no observed, empirical evidence for suggesting the earth is older than 6 to 10 thousand years. As this point, there are only 2 aspects of absolute dating that have not been discussed, radioactive decay rates and non-radiometric forms of absolute dating. We will cover each of these topics in our next 2 segments.

Focus on Critical Evidence: The Reliability of Decay Rates

Our first five segments on radiometric dating have now been completed. We have covered the basics of radiometric dating, the general obstacles to igneous and metamorphic dating, the particular obstacles facing the prominent potassium-argon method, the obstacles facing the carbon-14 method as well as the problems a global flood imposes on all these dating methods, and the minor remaining radiometric dating methods. Only one topic of radiometric dating remains: a direct examination of the radioactive decay rates. Although we have already demonstrated the incompetence of all the radiometric dating methods in detailed fashion throughout the preceding segments, we have saved a discussion of the decay rates until last because the problems with the decay rates affect almost all radiometric dating methods, with the possible exception of carbon-14 since it has a much shorter half-life. Thus, covering decay rates after sufficient proofs have already been provided against all radiometric dating methods functions as a final sweep or final nail in the coffin for radiometric dating.

First, it is important to restate the fact that radioactive decay rates must be known in order to calculate radiometric ages.

“Dating, Absolute dating, Principles of isotopic dating – 3. The decay constant must be known.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Dating, Absolute dating, Principles of isotopic dating – The age calculated is only as good as the existing knowledge of the decay rate and is valid only if this rate is constant over the time that elapsed.” – Encyclopaedia Britannica 2004 Deluxe Edition

In addition, as indicated by the last quote above, the decay rate must not only be accurate, but it must be a constant rate. In other words, the decay rate cannot change or fluctuate over time. If an incorrect rate is used in calculations or if the rate is non-constant but can change over time, then the age calculations will simply be incorrect and will either be too high or too low depending upon exactly how the actual decay rate differs from the rate used in the age calculation.

As established very early on in our discussion of radiometric dating, half-lives and decay rates are directly related.

“Geologic Time, III DATING METHODS – Radioactive elements decay to form elements or isotopes (atoms of an element that differ in mass but share the same general chemical properties) of an element. An element's half-life is the time required for half the number of its atoms to decay. Different elements can have dramatically different half-lives.” – "Geologic Time," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

“Dating, Absolute dating, Principles of isotopic dating – Half-life is defined as the time period that must elapse in order to halve the initial number of radioactive atoms. The half-life and the decay constant are inversely proportional because rapidly decaying radioisotopes have a high decay constant but a short half-life.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Dating Methods, III ABSOLUTE DATING METHODS. E Radiometric Dating, E1 Basic Theory – Scientists describe the radioactivity of an element in terms of half-life, the time the element takes to lose 50 percent of its activity by decay. This covers an extraordinary range of time, from billions of years to a few microseconds. At the end of the period constituting one half-life, half of the original quantity of radioactive element has decayed; after another half-life, half of what was left is halved again, leaving one-fourth of the original quantity, and so on. Every radioactive element has its own half-life; for example, that of carbon-14 is 5730 years and that of uranium-238 is 4.5 billion years.” – "Dating Methods," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

As indicated by the quotes above, half-lives are measurements in years of how long it will take for half the quantity of a particular radioactive isotope to decay into its daughter isotope. If a radioactive isotope decays quickly, it will take less time for half of that isotope to decay or change into another isotope. And conversely, radioactive isotopes with slower decay rates require more time in order for half of their quantity to decay into the daughter isotope.

And, as we also stated during our discussion of the basic concepts of radiometric dating, all radiometric dating methods are sorted into 2 categories based upon whether they have short half-lives or long half-lives. Furthermore, the quotes below assert that only carbon-14 dating and uranium-thorium fall into the category of isotopes with short half-lives. All other dating methods use isotopes with half-lives that are deemed to be long term.

“Dating, Absolute dating, Principles of isotopic dating – Of course, one must select geologic materials that contain elements with long half-lives—i.e., those for which some parent atoms would remain.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Dating, Absolute dating, Evaluation and presentation schemes in dating, Origin of radioactive elements used – When the elements in the Earth were first created, many radioactive isotopes were present. Of these, only the radioisotopes with extremely long half-lives remain…Natural elements that are still radioactive today produce daughter products at a very slow rate; hence, it is easy to date very old minerals but difficult to obtain the age of those formed in the recent geologic past. This follows from the fact that the amount of daughter isotopes present is so small that it is difficult to measure…Geologic events of the not-too-distant past are more easily dated by using recently formed radioisotopes with short half-lives that produce more daughter products per unit time. Two sources of such isotopes exist. In one case, intermediate isotopes in the uranium or thorium decay chain can become isolated in certain minerals due to differences in chemical properties and, once fixed, can decay to new isotopes, providing a measure of the time elapsed since they were isolated…Another special type of dating employs recently formed radioisotopes produced by cosmic-ray bombardment of target atoms at the Earth's surface or in the atmosphere. The amounts produced, although small, provide insight into many near-surface processes in the geologic past. This aspect of geology is becoming increasingly important as researchers try to read the global changes that took place during the Earth's recent past in an effort to understand or predict the future. The most widely used radioactive cosmogenic isotope is carbon of mass 14 (14C), which provides a method of dating events that have occurred over roughly the past 50,000 years.” – Encyclopaedia Britannica 2004 Deluxe Edition

Of course, it should also be stated that while carbon-14 has a short half-life of 5,730 years, the 2 different forms of the isotope thorium have half-lives of 10 billion and 80,000 years respectively.

“Dating Methods, III ABSOLUTE DATING METHODS. E Radiometric Dating, E1 Basic Theory – At the end of the period constituting one half-life, half of the original quantity of radioactive element has decayed; after another half-life, half of what was left is halved again, leaving one-fourth of the original quantity, and so on. Every radioactive element has its own half-life; for example, that of carbon-14 is 5730 years and that of uranium-238 is 4.5 billion years.” – "Dating Methods," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

“Radiocarbon – The radiocarbon already in the tissues continues to decrease at a constant rate. This steady decay at a known rate-a half-life of approximately 5,730 years-enables scientists to determine an object's age.” – Worldbook, Contributor: Rainer Berger, Ph.D., Professor of Anthropology, Geography, and Geophysics, University of California, Los Angeles.

“Thorium – Natural thorium is a mixture of radioactive isotopes, predominantly the very long-lived thorium-232 (1.41 × [10 to the 10th power or 10 billion] year half-life), the parent of the thorium radioactive-decay series.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Dating Methods, III ABSOLUTE DATING METHODS, E Radiometric Dating, E5 Methods Involving Thorium-230 – Thorium-230, part of the uranium-238 decay series, has a half-life of 80,000 years.” – "Dating Methods," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

Consequently, since the lowest thorium half-life is 80,000 years, thorium still falls under the category of dating methods that suffer from the primary issue surrounding radioactive isotopes with long half-lives. In short, for isotopes with short half-lives, such as carbon-14, their decay occurs within a short enough timeframe that a sufficient portion of it can be observed. As such, it can be confirmed that isotopes that decay quickly do so at exponential or constant rates. However, for isotopes with long half-lives, their decay occurs over such a long time that no human has or can observe it. In fact, their decay takes so long, that the fraction we can observe is not sufficient to consider it representative of the whole process. As such, it cannot be confirmed whether or not isotopes that decay over long periods are exponential and constant or instead vary and fluctuate over time. Consequently, constant and exponential rates have to be assumed for long half-life isotopes. And the sheer length of time decay requires in these isotopes is significant grounds for questioning whether or not the decay rate could or does remain constant over such exceedingly long spans.

The basis for assuming that radioactive decay rates remain constant and do not change even in isotopes with extremely long half-lives is expressed in the following quotes.

“Dating, Absolute dating, Principles of isotopic dating – The results show that there is no known process that can alter the rate of radioactive decay. By way of explanation it can be noted that since the cause of the process lies deep within the atomic nucleus, external forces such as extreme heat and pressure have no effect. The same is true regarding gravitational, magnetic, and electric fields, as well as the chemical state in which the atom resides. In short, the process of radioactive decay is immutable under all known conditions. Although it is impossible to predict when a particular atom will change, given a sufficient number of atoms, the rate of their decay is found to be constant.” – Encyclopaedia Britannica 2004 Deluxe Edition

“…there is no reason to doubt that the decay constants of the naturally occurring long-lived radioactive isotopes used for dating are invariant and independent of the physical and chemical conditions to which they have been subjected…” – Faure, G., Principles of Isotope Geology, 2nd ed., John Wiley & Sons, New York, p. 41, 1986 (Cited in “Radioactive Decay Update: Breaking Down the Old Age Paradigm,” Dr. Keith Wanser, AnswersInGenesis.org, Copyright 2003 Answers in Genesis, 4 minutes, 50 seconds)

According to Encyclopedia Britannica, we can be confident that decay rates are known, reliable, and constant because decay processes take place “within the atomic nucleus.” In short, decay rates are constant because they are governed by processes that occur in a location that is isolated from the influence of an “external forces.” Consequently, it is the concept that decay processes are isolated from forces outside the nucleus, which serves as the basis for assuming that decay rates remain constant. As such, the entire reliability of decay rates and the subsequent accuracy of radiometric ages comes down to whether or not radioactive decay really is isolated from any factors that would alter its rate of occurrence. And what we find is that there are 3 specific “external” factors that are known to altar decay rates, and in fact, decay rates in general are admitted to be alterable and non-constant.

The first external factor, which can alter decay rates, is cosmic ray bombardment. Cosmic rays are electrons and neutrons that travel throughout the galaxy unattached to atoms.

“Cosmic ray – a high-speed particle—either an atomic nucleus or an electron—that travels throughout the Milky Way Galaxy, including the solar system.” – Encyclopaedia Britannica 2004 Deluxe Edition

Below is an image depicting the affect that cosmic ray bombardment can have on an atom.

“[PHOTO CAPTION] Cosmic Rays – Cosmic rays are extremely energetic subatomic particles that travel through outer space at nearly the speed of light…A cosmic-ray particle produced the track that starts at the top left corner of the photograph; this particle collided with a nucleus in the center of the photograph to create a spray of subatomic particles. Powell-Fowler-Perkins/Photo Researchers, Inc.” – "Cosmic Rays," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

Additional insight into the ability of cosmic rays to trigger change in atomic structure can be seen in the fact that cosmic rays are the phenomenon that causes the nuclear changes, which create the radioactive isotope carbon-14.

“Dating, Absolute dating, Evaluation and presentation schemes in dating, Origin of radioactive elements used – Another special type of dating employs recently formed radioisotopes produced by cosmic-ray bombardment of target atoms at the Earth's surface or in the atmosphere…The most widely used radioactive cosmogenic isotope is carbon of mass 14 (14C), which provides a method of dating events that have occurred over roughly the past 50,000 years.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Carbon-14 dating – also called radiocarbon dating, method of age determination that depends upon the decay to nitrogen of radiocarbon (carbon-14). Carbon-14 is continually formed in nature by the interaction of neutrons with nitrogen-14 in the Earth's atmosphere; the neutrons required for this reaction are produced by cosmic rays interacting with the atmosphere.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Archeology, VIII DETERMINING THE AGE OF FINDS, B Absolute Dating, B3 Radiocarbon Dating – Radiation from space produces neutrons that enter the earth's atmosphere and react with nitrogen to produce the carbon isotope C-14 (carbon 14).” – "Archaeology," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

“Radiocarbon – In nature, radiocarbon forms when high-energy atomic particles called cosmic rays smash into Earth's atmosphere. Cosmic rays cause atoms in the atmosphere to break down into electrons, neutrons, protons, and other particles. Some neutrons strike the nuclei of nitrogen atoms in the atmosphere. Each of these nuclei absorbs a neutron and then loses a proton. In this way, a nitrogen atom becomes a radiocarbon atom.” – Worldbook, Contributor: Rainer Berger, Ph.D., Professor of Anthropology, Geography, and Geophysics, University of California, Los Angeles.

From their general interaction with atomic nuclei to their specific production of the radioactive isotope carbon-14, we know that cosmic rays can certain penetrate into the nuclear structure of an atom and affect the changes that transform one isotope into another. Consequently, cosmic rays meet the criteria necessary to impact decay rates. But does the neutron bombardment in cosmic rays actually trigger, not just isotope building, but isotope breakdown or decay?

The answer is “yes.” The fact that neutron bombardment can trigger decay is so well-known that inducing decay by neutron bombardment is actually a part of the fission-track absolute dating method, as indicated by the following quotes from Britannica Encyclopedia and Microsoft Encarta.

“Dating, Absolute dating, Major methods of isotopic dating, Fission-track dating – This is a special type of dating method that makes use of a microscope rather than a mass spectrometer, and capitalizes on damaged zones, or tracks, created in crystals during the spontaneous fission of uranium-238. In this unique type of radioactive decay, the nucleus of a single parent uranium atom splits into two fragments of similar mass with such force that a trail of crystal damage is left in the mineral…The sample is bombarded with slow (thermal) neutrons in a nuclear reactor, resulting in induced fission of uranium-235 (as opposed to spontaneous fission of uranium-238). The fission tracks produced by this process are recorded by a thin plastic film placed against the surface of the sample. The uranium content of the material can then be calculated so long as the neutron dose is known. The age of the sample is obtained using the equation, age = N × D s/D i × 6 × [10 to the power of 8], in which N is the total neutron dose expressed as neutrons per square centimetre and D s is the observed track density for spontaneous fission while D i is that for induced fission.” – Encyclopaedia Britannica 2004 Deluxe Edition

The next question to arise is this. Do cosmic rays come into contact with the wide variety of radioactive isotopes on earth that are used in radioactive dating? Or do cosmic rays remain solely in the upper atmosphere where they create only carbon-14? Once again, the answer is “yes,” cosmic rays do penetrate to the surface of the earth.

“Cosmic ray – Cosmic-ray studies have been carried out from far below the Earth's surface to outer space.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Cosmic rays – There are two kinds of cosmic rays: (1) primary cosmic rays, or primaries, which originate in outer space; and (2) secondary cosmic rays, or secondaries, which originate in the earth's atmosphere. Secondaries form when primaries collide with atoms at the top of the atmosphere. The collision changes the primary and the atom into a shower of secondaries. Many secondaries then collide with other atoms, making more secondaries. Some secondaries reach the surface and even penetrate deep into the ground. No measurable amount of primaries reaches the earth's surface…Secondary cosmic rays – Secondaries slow down in the atmosphere. Only a small fraction of them reach the earth. Every minute, about six secondaries strike each square inch of the earth. Because of the earth's magnetic field, the concentration is lower near the equator than near the poles…Since the 1960's, scientists have used balloons and spacecraft to study low- and medium-energy primaries. They have used large instruments on the ground to study secondaries.” – Worldbook, Contributor: R. B. McKibben, Ph.D., Senior Scientist, Enrico Fermi Institute, University of Chicago.

This is a fundamental problem that geochronologists have to deal with when performing absolute dating. Please note that the quotes attesting to this fact come from Microsoft Encarta.

“Geology, V Fields of Geology, B Historical Geology, B3 Geochronology – The determination of the age of rocks is called geochronology. The fundamental tool of geochronology is radiometric dating (the use of radioactive decay processes as recorded in earth materials to determine the numerical age of rocks)…Geologists also have ways to determine the ages of surfaces that have been exposed to the sun and to cosmic rays.” – "Geology," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

“Dating Methods, III ABSOLUTE DATING METHODS. E Radiometric Dating, E7 Fission-Track Dating – Rocks subjected to high temperatures or exposed to cosmic-ray bombardment at the earth's surface, however, may yield erroneous ages.” – "Dating Methods," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

In conclusion regarding cosmic rays, given that cosmic rays are admittedly able to penetrate to the surface of the earth and affect the decay rates in sample materials, it simply is not accurate to assert that decay rates are “immutable under all known conditions” and therefore can be assumed to be “constant” over long periods of time. Decay rates are quite alterable and this fact is so well known that scientists have to try to identify it in samples and some radioactive dating methods (particulalry fission-track dating) actually take advantage of the ability to affect decay rates by neutron bombardment.

The second external factor, which can alter decay rates, is the chemical environment surrounding the isotopes. As can be seen in the quotes below, the potential impact of the chemical environment is commonly denied in by secular and evolutionist sources.

“Dating, Absolute dating, Principles of isotopic dating – The results show that there is no known process that can alter the rate of radioactive decay. By way of explanation it can be noted that since the cause of the process lies deep within the atomic nucleus, external forces such as extreme heat and pressure have no effect. The same is true regarding gravitational, magnetic, and electric fields, as well as the chemical state in which the atom resides. In short, the process of radioactive decay is immutable under all known conditions. Although it is impossible to predict when a particular atom will change, given a sufficient number of atoms, the rate of their decay is found to be constant.” – Encyclopaedia Britannica 2004 Deluxe Edition

However, mainstream science publications probe the issue further and state that experimental evidence confirms the opposite conclusion, that the surrounding chemical environment does affect decay rates.

“A couple years back, there was this article published in Earth & Planetary Science Letters in 1999…indeed they found a fairly large dependence on radioactive decay rates for Beryllium 7 on the chemical species. In other words, the chemistry outside the nucleus is not supposed to have much of an effect on the nuclear decay rates. It’s supposed to be independent of the outside world, the nuclear decay rates. And here they found as much as a one and a half percent variation…That was a big deal at that time because before that time things were less than a tenth of a percent variation. So, we got one and a half percent variation with the chemical coordination that was around it. For instance, they had Beryllium, H20 with a four, so there are different hydroxides around it, different number of hydrogens and oxygens around the Beryllium nucleus, changes the electron density, how much electron clouds there are around the charged entity around the nucleus. And that affects the decay rates…But that’s not stunning. One and a half percent is not going to change things much.” – “Radioactive Decay Update: Breaking Down the Old Age Paradigm,” Dr. Keith Wanser, AnswersInGenesis.org, Copyright 2003 Answers in Genesis, 5 minutes, 15 seconds

While the percentage of change is in the case of Beryllium was not a large number, it’s occurrence does disprove the essential assumption that decay rates are not affected by chemical environment.

The third external factor, which can alter decay rates, can really be subdivided into 2 phenomena known as the Quantum Xeno Effect and the Quantum Anti-Xeno Effect. The Quantum Xeno Effect is a documented phenomenon in which decay rates are actually slowed down by repeated observation.

“In the secular literature, lots of folks are getting interested in acceleration of quantum decay processes and studying in a more fundamental way quantum decay processes because all of the stuff that was done early on was very crude and a lot of approximations. And there’s something called the Xeno Effect…What happens when you lift the pot and its boiling? If you lift the lid too often what happens? Does it ever finish cooking? A watched kettle doesn’t boil, if you keep watching it, too frequent observations. And that’s what they find in quantum mechanics. It’s called the Xeno Effect. The thing will never decay if you keep watching it, if you measure it too often to see if has decayed or not. It’s called the Quantum Xeno Effect.” – “Radioactive Decay Update: Breaking Down the Old Age Paradigm,” Dr. Keith Wanser, AnswersInGenesis.org, Copyright 2003 Answers in Genesis, 9 minutes and 20 seconds

Conversely, the Quantum Anti-Xeno Effect is also a documented phenomenon in which decay rates actually speed up by repeated observation.

“Well…there’s a Quantum Anti-Xeno Effect and that’s more interesting. Now, the Quantum Anti-Xeno Effect says if you start looking at something, you can actually perturb it and make it decay faster.” – “Radioactive Decay Update: Breaking Down the Old Age Paradigm,” Dr. Keith Wanser, AnswersInGenesis.org, Copyright 2003 Answers in Genesis, 10 minutes and 20 seconds

Once again, the Quantum Xeno and Anti-Xeno Effects demonstrates that the decay rates are not unaffected by external factors but instead, decay rates are indeed alterable.

Lastly, it is known that decay rates are generally alterable and non-constant. Creationist Dr. Keith Wanser sums up the current status in the following quote.

Once again, the idea that decay rates are alterable and non-constant is denied in by secular and evolutionist sources. However, mainstream science publications probe the issue further and state that experimental evidence confirms the opposite conclusion, that decay rates are alterable and non-constant. Here Dr. Wanser cites an article in the journal Nature titled, ““Acceleration of quantum decay processes by frequent observations,” by A.G. Kofman & G. Kurtzki of the Department of Chemical Physics at The Weizmann Institute of Science, Rehovet 76100, Israel. (This bibliographic information was provided by Dr. Wanser during his presentation.)

“This is a fairly recent article in Nature, June 2000, where they are sorting this out…There’s people out there who are studying these things and they find out there’s non-exponential decay all over the place…They’re finding out there really is non-exponential decay in a lot of systems, in a variety of systems…Before people inferred, they assumed they had exponential decay over unobservable times. They would take short-lived isotopes and…they could measure these exponential decays very accurately. But in the longer-lived ones you can’t measure whether it’s an exponential or not. And the question remains, is it an exponential? They have to assume an exponential decay law to get these long ages.” – “Radioactive Decay Update: Breaking Down the Old Age Paradigm,” Dr. Keith Wanser, AnswersInGenesis.org, Copyright 2003 Answers in Genesis, 10 minutes, 35 seconds

Dr. Wanser also cites other secular, evolutionary scientists who affirm that decay is not exponential and constant.

“A very famous guy, J. J. Sakurai, he’s a particle theorist. And in his textbook he has a whole section on how you get non-exponential decays (J. J. Sakurai, Modern Quantum Mechanics Revised Edition, 1994).” – “Radioactive Decay Update: Breaking Down the Old Age Paradigm,” Dr. Keith Wanser, AnswersInGenesis.org, Copyright 2003 Answers in Genesis, 11 minutes, 55 seconds

“Here’s another very recent paper, just came out in 2002, simulating some of the simplest things because it turns out that calculations in this business are very hard. They require lots of computing power and that’s one of the reasons why there hasn’t been a lot of progress. But, now people are starting to get enough computing power to be able to examine these things in detail. So, here it is again, some people in a secular situation, just examining the decay rate as a function of time. What happens? And here’s what they find…highly non-exponential decay. And this is just out of a very simple system…Nobody’s carefully investigated this for long-lived isotopes…it’s a little bit tricky of a problem. There are some complications…When things are really long-lived, you have to let the system go back and forth for about 10 to the fiftieth oscillations and that’s pretty hard for computers to go that many steps…Here they’re showing the difference between what you would get if it was constant decay…and you see this decay constant isn’t so constant.” – “Radioactive Decay Update: Breaking Down the Old Age Paradigm,” Dr. Keith Wanser, AnswersInGenesis.org, Copyright 2003 Answers in Genesis, 16 minutes, 40 seconds

In the quote above, notice the reference to the complexity of the equations and the enormous computing power required to perform such calculations. Britannica Encyclopedia affirms this also, specifically denoting the small number of laboratories capable of doing the computations for radiometric dating.

“Dating, General considerations, Determination of sequence – Relative geologic ages can be deduced in rock sequences consisting of sedimentary, metamorphic, or igneous rock units. In fact, they constitute an essential part in any precise isotopic, or absolute, dating program. Such is the case because most rocks simply cannot be isotopically dated. Therefore, a geologist must first determine relative ages and then locate the most favourable units for absolute dating. It is also important to note that relative ages are inherently more precise, since two or more units deposited minutes or years apart would have identical absolute ages but precisely defined relative ages. While absolute ages require expensive, complex analytical equipment, relative ages can be deduced from simple visual observations… The principles for relative age dating described above require no special equipment and can be applied by anyone on a local or regional scale. They are based on visual observations and simple logical deductions and rely on a correlation and integration of data that occurs in fragmentary form at many outcrop locations…Absolute dating, Principles of isotopic dating – The importance of internal checks as well as interlaboratory comparisons becomes all the more apparent when one realizes that geochronology laboratories are limited in number. Because of the expensive equipment necessary and the combination of geologic, chemical, and laboratory skills required, geochronology is usually carried out by teams of experts.” – Encyclopaedia Britannica 2004 Deluxe Edition

Furthermore, notice that in the following quote, the journal Nature is once again the source of the assertions about non-constant decay.

“Here’s another experimental evidence for non-exponential decay in quantum tunneling, another Nature paper, a mainstream journal. Nature is one of the most prestigious science journals there is…Here some people made an artificial quantum mechanical system…but they found out they had non-exponential decay at short times. They had faster decay at short times when they first set the system going.” – “Radioactive Decay Update: Breaking Down the Old Age Paradigm,” Dr. Keith Wanser, AnswersInGenesis.org, Copyright 2003 Answers in Genesis, 16 minutes, 10 seconds

According to Nature, decay rates are non-exponential and much faster when the system is first started. This is extremely relevant because it would relate to the conditions of the entire universe at creation. Decay rates would be much faster right after the entire universe started while rates today would be much slower. Consequently, assuming today’s rates yields erroneously large ages, when in reality, the present isotope ratios are completely compatible with a young earth in light of the realization that the decay rates were much faster when the universe first began.

The next quote discusses that high ionization has an impact in the magnitude of a billion-fold impact on decay rates.

“One of the things that really blew open the gates was when…John Woodmorappe…pointed out something in the physics literature that everybody seemed to have missed back in about 1996…This billion-fold acceleration of decay rates under certain specialized circumstances. Again, it can only happen in certain specialized circumstances…But, it shows us something very, very important…Here when they highly ionized some Rhenium atoms and they stripped off essentially all the electrons, like 80-some electrons or so, the decay rates would change by factors of 10 to the ninth. That’s a billion-fold change. What that meant is things that had a-billion-year half-lives went over into things that were half-lives of a day…Where are you going to have this process happen? Well, in a star environment, in a plasma environment, you strip off lots of electrons because it’s so hot. All the atoms are colliding with each other and they’re knocking off electrons. And people formerly were dating some kinds of stars with this Rhenium-Osmium chronometry and they found out their star dates were off by factors of 10 to the sixth, 10 to the seventh, and so on. And now, they’re taking this factor into account. But this is something that people didn’t really know about until 1996.”– “Radioactive Decay Update: Breaking Down the Old Age Paradigm,” Dr. Keith Wanser, AnswersInGenesis.org, Copyright 2003 Answers in Genesis, 18 minutes, 20 seconds

While this level of ionization only happens in environments like stars, it does show that high ionization impacts decay rates. This is important because, as we’ve already seen, mass spectrometers operate by highly ionizing the samples, which they are measuring for radioisotope decay.

“Mass spectrometry – Many investigations have been conducted with the help of mass spectrometry. These include the identification of the isotopes of the chemical elements and determination of their precise masses and relative abundances, the dating of geologic samples…” – Encyclopaedia Britannica 2004 Deluxe Edition

“Mass spectrometry – Mass spectroscopes consist of five basic parts: [1] a high vacuum system; [2] a sample handling system, through which the sample to be investigated can be introduced; [3] an ion source, in which a beam of charged particles characteristic of the sample can be produced; [4] an analyzer, in which the beam can be separated into its components; and [5] a detector or receiver by means of which the separated ion beams can be observed or collected.” – Encyclopaedia Britannica 2004 Deluxe Edition

Analysis, Instrumental methods, Separatory methods, Mass spectrometry – Most mass spectrometers have four major components: [1] an inlet system, [2] an ion source, [3] a mass analyzer, and [4] a detector. The inlet system is used to introduce the analyte and to convert it to a gas at reduced pressure. The gaseous analyte flows from the inlet system into the ionic source of the instrument where the analyte is converted to ions or ionic fragments.” – Encyclopaedia Britannica 2004 Deluxe Edition

“Mass Spectrometer, I INTRODUCTION – All mass spectrometers have four features in common: (1) a system for introducing the substance to be analyzed into the instrument; (2) a system for ionizing the substance; (3) an accelerator that directs the ions into the measuring apparatus; and (4) a system for separating the constituent ions and recording the mass spectrum of the substance.” – "Mass Spectrometer," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

“[PHOTO CAPTION] Mass Spectrometer – In a mass spectrometer, a sample of gas is ionized by an electron beam, and the ions are accelerated toward a magnet, which separates the ions according to their mass (upper right). Ions of a certain mass strike the detector; the detector is usually connected to a computer or other electronic device to process the data (bottom). © Microsoft Corporation. All Rights Reserved.” – "Mass Spectrometer," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation. All rights reserved.

While the ionization is magnitudes less than on stars, the influence of ionization on decay rates might still be present to a lower degree. It might not reduce decay rates from billions of years down to a day, but it might alter the decay rate enough to render radiometric dating calculations significantly inaccurate.

In conclusion to our examination of radioactive decay rates, we find that nearly all of the essential requirements for performing absolute dating calculations are unknown. The original parent-to-daughter isotopes remain unknown. Migration due to reheating events causes the amount of parent-to-daughter isotopes produced by decay to be unknowable. And decay rates for long half-life isotopes are not necessarily constant and exponential but may vary as a result of cosmic rays, the surrounding chemical environment, observation, how far we are from the start of the decay system, ionization, and simply as a general phenomenon. Consequently, the essentials needed in order to perform absolute dating (ratios and decay rates) are simply not available, which renders absolute dating unreliable and impossible. Furthermore, all of the discoveries in non-constant, non-exponential decay are fairly recent, ranging from 1994, 1996, 2000, 2002. This means that all of the radiometric dating used to calibrate the relative evolutionary timescale throughout the twentieth century was performed without taking into account that decay rates might be non-constant and non-exponential for long-lived half lives. Consequently, the support that absolute dating brought to the relative geologic timescale are shown to be premature and based upon inaccurate and unreliable assumptions.

(For an illustration of the missing factors that must be assumed in order to radiometrically calculate age see Dating Procedures Figure 8.)

Ultimately, the evolutionary timescale is without any empirical support. From start to finish it is merely the product of speculation, assumption, and philosophical preference. There remains no empirical evidence negating the creationist history of the earth 6 to 10 thousand years ago, a history that is demonstrated by physical geologic data and the historic record.

Having finished our investigations into the specific issues and problems of radiometric dating, the next segment will conclude our focus on radiometric dating by taking a look at the general status of radiometric dating in the words of secular and evolutionary sources.