AGE IS IN THE EYE OF THE BEHOLDER

It is not true that we can assume any rock has been undisturbed for billions of years. Perhaps in every rock, some radioactivity has been lost by processes have nothing to do with radioactive decay. This means a rock appearing old could actually be quite young. The fallacy of this assumption has been clarified in some striking examples. In 1973, for instance, fossils formed almost instantly when a high voltage power line fell and struck some vegetation in Alberta, Canada. According to experts, these fossils would have been dated at millions of years by radiometric methods with the usual assumptions.

Sometimes fossils are found encased in igneous rock. Igneous rocks form as lava from volcanic eruptions cools and solidifies, and living things can be buried in such eruptions. One such fossil is the human skull found in Kenya dubbed KNM ER-1470. Though human, it has been dated by radiometric techniques at 2.8 million years -- older than the apes even on the evolutionary time scale! This skull was not itself dated directly, but was dated by the igneous rock that held it.

Although the skull certainly has the same age as the lava rock in which it was found, the reported age of the lava is incorrect. The lava's low radioactive content allegedly meant old age -- but the lava had been exposed to rain and groundwater for centuries! The ages of many ancient humans -- so-called "ape-men" -- would doubtless be revised downward if such false assumptions were corrected. In fact, it has been shown that the age of any rock would be revised to virtually zero if the use of false assumptions were eliminated. Of course, evolutionary philosophy cannot tolerate this fact, but we can see that conventional dating methods have no practical usefulness as far as the age of the earth is concerned.

We have now considered two assumptions typically employed in radiometric techniques. We are ready to consider assumption number three. Assumption number three is that the rate of radioactive decay has never changed (see Note 10). Only if this assumption is true can we have a predictable progression from the higher radioactive content of a new sample to the lower content of an old one. Even if the first two assumptions are true -- the sample has been undisturbed, and we can know its original level of radioactivity -- without assumption three we still cannot know how long it took for the radioactivity to drop from the higher ancient level to the lower modern level.

Now let's examine assumption number three, the claim that radioactive decay rates have never changed. Evidence in the form of "radiohalos" shows this claim is not true. Radiohalos are microscopic spheres of discoloration which surround radioactive mineral grains in rock (see Note 11). They must be viewed under a microscope to be seen. Many of the mineral grains responsible for radiohalos contain atoms of the radioactive element polonium. As polonium atoms decay, they explode and spew nuclear debris into the surrounding rock. This "nuclear shrapnel" discolors the rock, but rock is quite dense and the "shrapnel" doesn't penetrate a great distance. Hence the spheres or halos of discoloration remain microscopically small.

Polonium comes in several forms, two of which are polonium-218 and polonium-214. These different forms of polonium produce different size halos. However, radiohalo size depends not only on the kind of atom decaying and causing the discoloration, but also on the rate of radioactive decay. When atoms decay at a faster rate, nuclear fragments -- emissions -- also exit the nucleus at higher speeds than when decay rates are lower. Before coming to a stop, high-velocity debris penetrates farther into surrounding rock and forms a bigger halo. If radioactive decay rates had always been the same, halos would have sharp edges. Changing decay rates result in halos with fuzzy edges -- and most halos are fuzzy! The fuzziness or variation in halo size shows that radioactive decay rates have not been constant.

Other evidence also shows that radioactive decay rates in the past were not simply different, but were actually higher. Lab data show a steady decline in decay rates since the early 1900s. With faster decay rates in the past, rocks could have lost much radioactivity and appear old, yet really be quite young. Lab data also show that temperature, pressure, chemical concentrations, and other factors can alter radioactive decay rates.

We have now looked at some problems in arriving at ages for rocks, but in fact all we have said about rocks so far applies only to igneous rocks, the kind formed in volcanic eruptions as magma or lava cools. Now we will consider how evolutionary philosophy arrives at ages for fossils and fossil-bearing rocks. From a Biblical perspective we know that fossils and the rocks containing them are more recent than the creation several thousand years ago. But evolutionary philosophy claims fossils and their rocks are millions (occasionally billions) of years old.