Numerous geochronometers (clocks') have been used to measure the age of the Earth. There are at least two requirements for any 'clock'. First, it must be assumed that the 'clock' has been running at the same rate throughout past years (this is really the Theory of Uniformitarianism - that the rate at which things are happening has been constant from the beginning). Secondly, some idea must be obtained as to how tightly the 'clock' was wound initially (eg. when using the depth of cosmic dust as a geochronometer, it is important to know if a layer was present initially).

Such dating methods have given vastly differing values for the age of the Earth (eg. salt in sea-water gives 50 - 90 million years; helium gas in the atmosphere gives 26 million years; meteorites since solidification) have been dated at 60 million years from their helium content, but as much as 4,600 million years using the Potassium-Argon Method).

Atoms of elements each consist of a nucleus containing protons (positively charged) and neutrons (no charge) surrounded by electrons (negatively charged). The number of protons equals the number of electrons and the whole is rather like a miniature planetary system. The number of electrons (and their arrangement) governs the reactivity of the element. Elements can exist in the form of isotopes, characterised by the same number of protons and electrons as the parent element, but having a different number of neutrons (thus the mass number varies), but the parent and isotope have similar chemical properties. Many isotopes decay (ie. they are converted to other elements, and in so doing they radiate alpha-particles, beta-rays, or gamma-rays, which can be measured). For any isotope, a 'decay curve' can be drawn showing that after its 'half-life', 50 percent of the isotope has been lost, and after a further equal time, half of the remainder - and so on. Examples of 'half-lives' of some isotopes used for radiometric dating are: Tritium 12.3 years; 14Carbon 5,730 years: 40Potassium 1,300 million years; 238Uranium 4,510 million years.

As 40Potassium and 238Uranium, for example, are found in rocks, this provides a means of dating, if;

(1) the 'half-life' is known and has been constant throughout time;

(2) the amount of radioactivity in the sample is measured;

(3) the amount of the product present now is known; and

(4) the initial amount of radioactive substance is determined (ie. the amount present immediately after crystallisation of the mineral.

This last requirement is virtually impossible to arrive at since we are unable to go back in time to analyse the mineral concerned.

Furthermore, there is much evidence now to indicate that 'half-lives' of isotopes (measured in the laboratory) have not been constant during the past. It is generally thought that isotopes are associated with cosmic ray bombardment (i.e. neutron bombardment) from outer space. Most think that the amount of cosmic radiation reaching the Earth has been constant for thousands of years, but this is NOT TRUE. There are at least two factors involved that undoubtedly result in a changing cosmic radiation intensity. Thus although the 'half- life' may be constant in the laboratory, there is no guarantee that it will remain so in a rock that is open to the elements. Further complications arise with regard to the initial amount of radioactive material and the amount of decay product. It has to be assumed that this was formed solely by radioactive decay processes. What if it were formed by some other (or additional) mechanism; what if the product itself were lost to a greater or lesser extent from the mineral, or alternatively, the concentration of the initial isotope varied with weathering conditions?

Let us consider some of these criticisms in relation to radioactive 'clocks':-

Uranium-Thorium-Lead Method

This has been used since 1907, but more recently has been superseded by the Potassium-Argon method. It depends on the decay of the 238Uranium isotope to give eventually lead and helium. It is not known if part of the product leads were produced by some other method (apart from radioactive decay), and conceivable that some of the lead isotopes may have been present initially - no one knows. Furthermore, there is good evidence that helium (being a light gas) can escape readily from rocks into the atmosphere. It has also been shown that 238Uranium can be leached out of rocks; even granite. 10,000-50,000 tons of uranium are washed into the sea annually. Thus, if a mineral at time T was found to contain a certain amount of the initial isotope 238U, which in fact had been depleted by weathering and decay, the mineral would appear older by an enormous and indeterminate amount. A similar erroneous result would be obtained if the product helium were being measured.

Potassium-Argon Method

Similar criticism may be levelled at this method. In it, the isotope 40Potassium changes into 40Argon (11 ) and 40Calcium (89). The first problem is that two pro- ducts are formed, the minor one being 40Argon and the major one 40Calcium. The so-called 'branching ratio' has not been measured with any certainty, and the value used can alter the age value of the mineral concerned by an appreciable amount. The isotope of calcium is not useful to measure as calcium is so common in rocks: 40Argon is always used for age determinations. Here there are many problems:

(a) The amount of 40Argon in the Earth's atmosphere is 100 times too high for it all to have been produced by radioactive decay of 40Potassium, even if 4,500 million years are invoked! Therefore much of this must have been there initially.

(b) 40Argon (like Helium, above) is a gas that is known to diffuse easily from the rocks, depend- ing on the porosity of the surface, and on the prevailing pressure. Thus rocks deeper in the Earth's crust where pressure is high, will loose 40Argon to rocks nearer to the surface where pressure is lower. Furthermore, 40Argon will be lost to different degrees from different types of minerals. Thus, surface rocks, used for age determination, will have a higher 40Argon content than would be expected, suggesting great age.

(c) Volcanic rocks have inherited 40Argon from the Earth's magma (molten core) in formation. This would again suggest erroneously great ages for these that have erupted into the ocean. Two ages were reported in 1968. Lavas taken from the ocean bed near Hawaii were dated at 22 million years by the Potassium- Argon Method, but the actual flow is known to have occurred less than 200 years ago!

(d) Potassium is easily washed out of minerals. For example, an iron meteorite lost 80 of its Potassium by running distilled water over it for only 4 /2 hours. Rocks subjected to weathering conditions loose Potassium, thus indicating that the 40Potassium has had vast ages in which to decay to these very small values.

Rubidium-Strontium Method

Similar criticisms have been levelled at this by a number of writers, but they will not be discussed here.

Many skulls and other bones, found in various parts of the world have been dated - not by dating the bone itself - but by dating the rock stratum in which the remains were found. The Potassium-Argon Method applied to Zinanthropus boseii (Nutcracker Man) gave ages for the stratum above as 1.75 million years, for the stratum below as 1.5 million years and for the layer of basalt immediately below that as 1 million years or even less. It should be noticed that:

(a) the ages are the wrong way round - the lower stratum should be older, and

(b) that there is an enormous variation in ages by the same method.

The 14Carbon Dating Method

This was introduced in 1948 by W.F. Libby as a method for dating human, animal and vegetable remains of relatively recent origin. 14Carbon is the long-lived isotope of 12Carbon, the 'half-life' of radioactive decay being approximately 5,730 years. 14Carbon is made from nitrogen gas in the upper atmosphere through neutron bombardment from powerful cosmic radiation. The 14Carbon so formed is converted into 14Carbon dioxide, finds its way into living things and is 'fixed' at death. But, although the method has been used extensively in dating archaeological finds, numerous as- sumptions have to be made:

(a) that the 'half-life' of 14Carbon has not varied over the years.

(b) That the rate of formation of 14Carbon has - been constant.

(c) That the concentration of 14Carbon in the atmosphere is constant.

(d) That the ordinary carbon dioxide must be constant - otherwise this could dilute (or enrich) the 14Carbon dioxide content.

(e) That the rate of formation and the rate of decay of 14Carbon have been in equilibrium.

Only three of these assumptions will be examined here. First, it is .an unwarranted assumption that the 'half-life' of 14Carbon has not varied with time. There is evidence now to show the opposite with various isotopes such as 238Uranium and 57lron. Secondly, the rate of formation of 14Carbon (and hence 14Carbon dioxide) and thirdly its concentration have not been constant for two reasons:

(1) Since the Industrial Revolution, more ordi- nary carbon dioxide has been released into the atmosphere until about 1950, when testing atomic devices began to release neutrons thus increasing the 14Carbon content.

(2) The amount of cosmic radiation reaching the Earth's atmosphere cannot be assumed constant throughout world history. It is highly probable that the earth was shielded by a vapour canopy in the past, as suggested by Korff in 1954. Such a water vapour shield would have had the effect of reducing the amount of cosmic radiation entering the Earth's atmosphere - hence less 14Carbon would have been formed prior to the precipitation of water at the Flood, resulting in considerable over-estimates of age.

Thus, when these assumptions are examined critically, it is obvious that the dating method on which they are based gives highly questionable ages for specimens supposedly 10,000 years old. Indeed, it is now generally accepted that the method is only of use in dating materials of between 5,000 and, at most, 10,000 years ago.

R.L.Whitelaw (1970) has collected data on 15,000 14Carbon dates and grouped these in relation to the numbers of human, animal and plant remains. A number of significant points emerge:

(1) The number of human and animal remains increases from about 7,000 years ago to about 5,000 years ago, after which there is an abrupt decrease to one-sixth or one-tenth of the number.

(2) The number thereafter gradually increases to the present.

(3) At both the 7,000 and 5,000 year time, the number of 14Carbon dates in North and South America lags behind those found in Afro-Eurasia.

(4) The number of trees dated is very high initially (7,000 years ago) compared with animal and human remains and decreases markedly at about 5,000 years before the present time. Whitelaw suggests that these data are consistent with a young age for the Creation (approximately 7,000 years ago), and with the fact of a world-wide Flood 5,000 years ago. Further- more, they are consistent with creation of living things occurring in the Middle East, with a population of the Western Hemisphere occurring somewhat later. Similarly, after the Flood Africa-Eurasia was populated far more rapidly than North and South America. The very large number of tree deaths initially may be consistent with the luxurious vegetation that is implied in the Genesis account - vegetation that was almost wiped out by the Flood, and which has never increased to the former extent, presumably because of climatic conditions.



This study of the annual growth rings of trees has been useful in estimating age.

Trees found in the White Mountains of Arizona are reckoned to be some 4,000 years old as judged by a microscopic study of their growth rings. Since this method can be used for both living and dead wood, it has proved to be a useful check on the 14Carbon Method. It is particularly significant that no one has round stumps of such trees, even though this species is known to be disease- and pest-resistant. It is most likely that these trees represent the first generation after the Flood.

Population Statistics

This method gives a measure of the time since the Flood. It is assumed that the Scriptural record is true, and that only eight people survived the global catastrophe - Noah, his wife, three sons and their wives. The World Population is now approximately 2,500 million. This would be reached in 30 doublings of the population in periods of 175 years each (ie. 5,250 years, thus dating the Flood at approximately 3300 B.C.

Studies on the Magnetic Field of the Earth

The Magnetic Field was studied in 1835 by Gauss and by Lamb in the 1880's. More recently, many other measurements have been made at different points on the Earth's surface, up to 1970. The Field is thought to arise in the molten core, which is 20 iron and has excellent electrical conductivity. Lamb showed mathematically that the Magnetic Field, which shields the Earth from cosmic radiation, would decay exponentially to a certain percentage of its original value in approximately 100,000 years through dissipation of heat to the Earth's crust (Joule heating effect). This is discounted by those who state that the Earth's age is 4,500 million years. The implications of the diminishing field are:

(1) That there will be an end to the Earth, possibly by cosmic ray bombardment.

(2) If this cosmic radiation intensity has not been constant, this would have affected 14Car- bon formation and hence, the accuracy of 14Carbon dates.

(3) The decay curve has only to be extrapolated backwards for about 8,000 years before the Earth's magnetic moment would equal that of a magnetic star - a most unlikely occurrence.

(4) The Joule heating effect in the Earth's core would have been enormous with such vast magnetic moment.

These evidences argue strongly for an age of a few thousand years for the Earth.

Author: Professor D.B.Gower.

Pamphlet 207.      Creation Science Movement

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