jeudi 7 juillet 2011

Why so shy about creationist pov on C14?

Religious Tolerance is a site supporting deism.

Here is their take on why creationists reject Carbon 14 dating:

http://www.religioustolerance.org/c14datc.htm

ChristianAnswers.net states: "Outside the range of recorded history, calibration of the 14C clock is not possible."


This was true back in the 1950s. A team of researchers, headed by Willard F. Libby calibrated the C-14 measuring technique by comparing the measured age of samples from ancient Egypt with their known date. For example, they tested a piece of wood from Pharaoh Zoser's tomb with the known tomb date, which was known to be circa 2700 to 2600 BCE. The agreement was excellent. Since then, extended calibration checks have been made using U.S. bristlecone pine, German and Irish oak, and other species of trees. That work pushed the calibration back well beyond recorded history to 10,000 BP (years before the present.) Other correlations have extended that to 26,000 years BP. It may eventually go back as far as 45,000 years, which is the approximate limit of the C-14 technique. 6


Right.

Not really. And this is a key issue according to the site:

http://www.religioustolerance.org/ev_disp.htm

The foundational observations which support evolution are the ordered fossil record and radiometric analysis of the dates of rocks.
  • If the radiometric analysis of the age of rocks is valid, then two main beliefs of young-earth creation scientists are disproved.
    • The rock layers were deposited over billions of years, not during the 150 days of Noah's flood.
    • That the earth is on the order of 4.6 billion years old, not many thousands of years old.


Still, if some convincing proof were discovered that the radiometric analyses are in error by about a factor of 500,000 or so, and that the earth is fewer than 10,000 years of age, then evolution would be disproved. There simply would not have been sufficient time for all of the new species to have evolved. Six specialists in geology, geochemistry and physics have formed the Radioisotopes and the Age of the Earth (RATE) research group. They have been working since 1997 to disprove radiometric dating, to prove that the earth is young, and thereby disprove evolution. 8


The site fails to mention a pretty standard creationist point of view in more words than the forequoted: "Outside the range of recorded history, calibration of the 14C clock is not possible" - from Christian Answers.

C14 is not an invariant per se in the athmosphere, it is more or less invariant - some variations are recorded - due to two opposing dynamics:
  • cosmic rays build up C14, exposure times exposable original isotope
  • radioactive decay tears down C14 to non-radioactive isotope, in a ratio to what amount of C14 there is already.


This means when there is little or none C14, the build up exceeds the tear down. This means that a young earth scenario implies the possibility of C14 not yet fully built up to equilibrial level, either even now or at least recently.

Now, that, in turn, does imply if not proof of fact as such at least a very clear possibility of datings being wrong at very high ratios. Not so much the C14 datings - we will return to other ones - but even those can be wrong by high ratios. A sample without any C14 - is it from 45.000 before present or older or from the day after Adam tasted the apple, the first plant or beast that died as a consequence of human sin, at a time when there was no C14?

The dating would be wrong, not due to any miscalculation on part of scientists, but due to misapplication of calculations, according to false presuppositions. For other dating methods, other presuppositions would be the wrong ones. But evolutionists would - for the very reason stated in second quote from Religious Tolerance site - tend to make precisely the assumptions that would give too high ages, not the ones that would give too low ones.

Thorium-Lead and Uranium-Lead methods repose not only on an assumption of very much slower radioactive decay (we know that Uranium at least sometimes decays very fast in nuclear chain reactions) but also the assumption that the lead isotopes associated with samples conatining either Uranium or Thorium (to be fair, they are two different isotopes!) all come from decay of Uranium and Thorium.

As for dendrochronology - important because Religious Tolerance site stated it has pushed calibration of C14 beyond 10.000 before present - the main reaction is: "we buy the dendrochronology of the living trees, but there have in taking the chain through dead ones been mismatches, there have been matchings were matches were not taken for best matches but for oldest datings". Basically, about the accuracy there is word against word, and we laymen cannot verify, because we have often not the time, and certainly nearly never the skill for testing match after match between sample pair after sample pair. Assuming one would get the access. And assuming variations in tree rings are globally consistent.

Now that is a point of view pretty common among young earth creationists. And it is not stated in so many words but instead the site choses the shortest possible quote and refutes it without bothering that the other side has already refuted their refutation. I will now highlight a part of the second quote:

Six specialists in geology, geochemistry and physics have formed the Radioisotopes and the Age of the Earth (RATE) research group. They have been working since 1997 to disprove radiometric dating, to prove that the earth is young, and thereby disprove evolution.


So datings can either be proven right or proven wrong, but not simply argued to be not proven? Now that is a show of fairness and open mind, along with a real close mindedness. The possibility of datings being argued not proven is the classical young earth creationist take, and it was well known before 1997. If you do not know that, the RATE group seems to prove conventional science takes creationism seriously with an open mind. If you do know this, it staggers belief they left out from the mission statement "or argue that old datings are not proven, on the lines already suggested by creationists" or words to same effect.

Hans-Georg Lundahl
BU de Beauvais
7-VII-2011