The lowest age defended on a scientific basis is in the 6 to 10 thousand year range. Evolutionism, of course, requires billions of years to support the plausibility of life's emergence and of subsequent Evolution from "amoeba" to man. Theoretically, Creationism remains workable within a wide range of age estimates.

ASSUMPTION: Evolutionists generally assume the material being measured had no original "daughter" element(s) in it, or they assume the amount can be accurately estimated. For example, they may assume that all of the lead in a rock was produced by the decay of its uranium.

PROBLEM: One can almost never know with absolute certainty how much radioactive or daughter substance was present at the start.

When a material incorporates both the parent and daughter nuclides at the time of formation, it may be necessary to assume that the initial proportions of a radioactive substance and its daughter are known. The daughter product should not be a small-molecule gas that can leak out of the material, and it must itself have a long enough half-life that it will be present in significant amounts. In addition, the initial element and the decay product should not be produced or depleted in significant amounts by other reactions.

ASSUMPTION: Evolutionists have also tended to assume that the material being measured has been in a closed system. It has often been wrongly assumed that no outside factors altered the normal ratios in the material, adding or subtracting any of the elements involved.

PROBLEM: The age estimate can be thrown off considerably, if the radioactive element or the daughter element is leached in or leached out of the sample.

There are evidences that this could be a significant problem. Simple things such as groundwater movement can carry radioactive material or the daughter element into or out of rock. Rocks must be carefully tested to determine what outside factors might have changed their content.

ASSUMPTION: They assume that the rate of decomposition has always remained constant - absolutely constant.

PROBLEM: How can one be certain that decay rates have been constant over billions of years? Scientific measurements of decay rates have only been conducted since the time of the Curies in the early 1900s.

Yet Evolutionists are boldly making huge extrapolations back over 4.5 billion years and more. There is some evidence that the rate of radioactive decay can change. If the decay rates have ever been higher in the past, then relatively young rocks would wrongly "date" as being old rocks.

Your argument rings of Uniformitarianism. Firstly, this argument is self-defeating. To assume anti-uniformitarianism (a legitimate scientific debate) one must assume the Earth is millions or billions of years old. We can measure the conditions of the last 10 000 years so accurately now that we can be certain that the cataclysm of the conditions necessary to increase radioactivity that much could only have existed long before advanced life, as such bombardment would have inevitably shut down any evolutionary projects. Anti-uniformitarianism only calls into question the accuracy of ultra-slow isotopes like U238, which halves in over 4.5 billion. years. It does not affect fast isotopes like C-14, which we can measure only to the past 60,000 years. Going back this recently, radioactivity could not have increased at all in such a short time span unless our Neanderthal ancestors were performing atomic blast tests.

Evolutionist William Stansfield, Ph.D., California Polytech State, has stated:

"It is obvious that radiometric techniques may not be the absolute dating methods that they are claimed to be. Age estimates on a given geological stratum by different radiometric methods are often quite different (sometimes by hundreds of millions of years). There is no absolutely reliable long-term radiological 'clock'."

There has been in recent years the horrible realization that radio-decay rates are not as constant as previously thought, nor are they immune to environmental influences.

And this could mean that the atomic clocks are reset during some global disaster, and events which brought the Mesozoic to a close may not be 65 million years ago, but rather, within the age and memory of man."

it (the half-time) is not affected^[2] by external factors such as temperature, chemical environment, or presence of a magnetic or electric field. (For nuclides which decay by the process of electron capture, such as Beryllium-7, Strontium-85, and Zirconium-89, the decay rate may be affected by local electron density, therefore these isotopes are not used for radiometric dating.) Although decay can also be accelerated by radioactive bombardment, such bombardment tends to leave evidence of its occurrence.