It is hypothesised that the accretion of Earth began soon after the formation of the calcium-aluminium-rich inclusions and the meteorites.Because the exact amount of time this accretion process took is not yet known, and the predictions from different accretion models range from a few million up to about 100 million years, the exact age of Earth is difficult to determine.Steven Austin rightly wonders, "Has anyone successfully dated a Grand Canyon rock? The validity of the calculated date can be no stronger than the weakest link (weakest assumption) used in the calculation.

There is no absolutely reliable long-term radiological 'clock'." "The age of our globe is presently thought to be some 4.5 billion years, based on radio-decay rates of uranium and thorium.

Such ‘confirmation’ may be shortlived, as nature is not to be discovered quite so easily.

The speed of the disintegration process is measured.

A portion of the material is ground up and a measurement is made of the ratio of radioactive “parent” atoms to the decomposition products.

It disintegrates at a measured rate into calcium and argon.

Similarly, the radioactive element uranium decomposes into lead and some other elements.

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." Author: Paul S. Copyright © 1998, Films for Christ, All Rights Reserved—except as noted on attached “Usage and Copyright” page that grants Christian Answers.

By the way, it is important to understand that most rock strata “dates” were actually assigned long before the first use of radioactive age estimating methods in 1911.

The Carbon-14 age estimating method is, at best, only useful for estimating the age of things that are thousands of years old, not millions or billions.

Age estimates which are obviously wrong or contradictory are sometimes produced.