Posted on 08/17/2012 11:21:22 AM PDT by fishtank
More Fluctuations Found in Isotopic Clocks
by Brian Thomas, M.S. | Aug. 17, 2012
Age-dating a rock using its radioactive isotopes only works by assuming that the rate at which that "clock" ticks was constant in the past and essentially identical to that in the present. Not long ago, scientists discovered excess helium in crystals1 and "orphaned" polonium radiohalos,2 both of which imply that the decay rates of isotopes commonly used to date earth rocks were dramatically accelerated in the past. Even today, researchers are finding small but significant changes in isotope decay rates, and these add credibility to the idea that isotopic processes were once very different from today's processes.
One standard isotopic clock system uses decaying uranium isotopes. Uranium spontaneously and slowly decays to lead (Pb on the Periodic Table of Elements). Two different uranium isotopes, 235U and 238U, decay into lead at different rates. Geologists assume that the ratio between these is constant and known, giving a convenient shortcut to uranium dating, which only requires that the two uranium amounts be measured.
Of course, this shortcut age-dating method assumes that 238U and 235U have decayed at today's rates throughout the past. It also assumes that the relative amounts of the two have been constant. Physics Today editor Johanna Miller recently wrote, "Standard Pb-Pb dating protocol uses a 238U/235U ratio of 137.88 with zero uncertainty. But several recent studies have cast doubt on that number."3
Miller cited one experiment that found that the uranium ratio (the heavier 238U to lighter weight 235U) is not constant. The study authors wrote, "Our observations have a direct impact on the U-series and U-Th-Pb chronometers," meaning that dates "determined" by uranium decay will need revision.4
Yet another study reported natural variation in the uranium ratio. These authors suggested that natural processes separate the isotopes from one another and skew the ratio, thereby skewing the ages gained by the assumption that the ratio was constant. These authors wrote, "The discovery that 238U/235U varies in nature also has implications for the precision and accuracy of U-Pb dating. The total observed range in U isotope compositions would produce variations in 207Pb/206Pb ages of young U-bearing minerals of up to 3 Ma [million years old], and up to 2 Ma for minerals that are 3 billion years old."5
Two to three million years are not a huge part of three billion. So, adjusting already-published dates to reflect these new and larger error margins will not displace billion-year-old age assignments. However, if today's comparatively tame natural processes affect isotope ratios, then ancient and much more violent processes could have affected those ratios and rates much more, just as the helium in crystals and orphaned radiohalos imply.
Another isotope system used for dating, though more rarely that uranium, is that which occurs when a radioactive samarium isotope decays to the element neodymium. A 2012 Science report re-measured samarium's decay rate, finding that it occurs only about 66 percent as fast as "the currently used value" for age dating.6 This is a huge discrepancy! It means that all published samarium-dated rock ages need to be re-evaluated.
In addition, Purdue University just applied for a patent on a solar flare warning system that relies on ways in which the earth-sun relationship somehow alters nuclear decay rates. Purdue News reports that "Advance warning could allow satellite and power grid operators to take steps to minimize impact and astronauts to shield themselves from potentially lethal radiation emitted during solar storms."7 Their invention would rely on detecting changes in the rate of manganese 54 decaying to chromium 54. Researchers observed the decay rate changes occurring about a day prior to solar flares.
Even carbon dating is in hot water. Scientists typically use this method to age-date carbon-containing objects thought to be only tens of thousands of years old. The relevant radioactive carbon isotope (14C) decays so fast that it should no longer exist in earth materials that are a million or more years old.8 Recently, researchers measured elevated levels of 14C in correlated tree rings and attributed the spike to an unidentified "massive cosmic event."9 If natural processes did alter carbon isotope ratios, then why trust dates that assume the ratios were never altered?
Science shows that isotopic clocks are not all trustworthy.10 The isotope ratios and rates upon which they depend are variable, even on today's comparatively calm earth surface. During the tumultuous Flood, when immeasurable quantities of mantle material were ejected onto earth's surface and water potentially contaminated everything, isotopic clocks ticked much, much faster.11
References
Humphreys, D.R. 2005. Young Helium Diffusion Age of Zircons Supports Accelerated Nuclear Decay. In Radioisotopes and the Age of the Earth: Results of a Young-Earth Creationist Research Initiative, Vol. 2. Vardiman, L. et al., eds. El Cajon, CA: Institute for Creation Research and Chino Valley, AZ: Creation Research Society.
Gentry, R.V. 1974. Radiohalos in a Radiochronological and Cosmolocial Perspective. Science. 184 (4132): 62-66.
Miller, J. 2012. Time to reset isotopic clocks? Physics Today. 65 (6): 20-21.
Stirling, C.H. et al. 2007. Low-temperature isotopic fractionation of uranium. Earth and Planetary Science Letters. 264 (1): 208-225.
Weyer, S. et al. 2008. Natural fractionation of 238U/235U. Geochimica et Cosmochimica Acta. 72 (2): 345-359.
Kinoshita, N. et al. 2012. A Shorter 146Sm Half-Life Measured and Implications for 146Sm-142Nd Chronology in the Solar System. Science. 335 (6076): 1614-1617.
Venere, E. New system could predict solar flares, give advance warning. Purdue News. Posted on purdue.edu, August 13, 2012. Despite this, 90 instances of C-14 in supposedly million-year-old earth materials were reviewed and 10 more were presented in Baumgardner, J.R. et al. 2003. Measurable 14C in Fossilized Organic Materials: Confirming the Young Earth Creation-Flood Model. In Proceedings of the Fifth International Conference on Creationism. R.L. Ivey, ed. Pittsburgh, PA: Creation Science Fellowship, Inc., 127-142.
Lovett, R. A. Mysterious radiation burst recorded in tree rings. Nature news. Posted on nature.com June 3, 2012, accessed August 10, 2012.
Austin, S.A. 2005. Do Radioisotope Clocks Need Repair? Testing the Assumptions of Isochron Dating Using K-Ar, Rb-Sr, Sm-Nd, and Pb-Pb Isotopes. In Radioisotopes and the Age of the Earth: Results of a Young-Earth Creationist Research Initiative, Vol. 2.Vardiman, L.et al., eds. El Cajon, CA: Institute for Creation Research and Chino Valley, AZ: Creation Research Society. When heated to plasma, bare nuclei of rhenium radioisotopes decay a billion times faster than normal. See Bosch, F. et al. 1996. Observation of Bound-State β- Decay of Fully Ionized 187Re: 187Re- 187Os Cosmochronometry. Physical Review Letters. 77 (26): 5190-5193.
* Mr. Thomas is Science Writer at the Institute for Creation Research.
Article posted on August 17, 2012.
I like to entertain ideas about time.
I saw a show with some smart guy that suggested that time was an illusion. We are living in what I can only describe as “slices of space”.
Entertaining indeed, and hard to get your head around.
I’m not suggesting that I believe this. But as a thought experiment it can get interesting.
From my perspective, the only way time can be an illusion is if our entire universe is moving at or very near the speed of light.
There is of course no way to prove this.
Nevertheless, climate science is settled.
The best argument against these climate guys is that none of them can explain how we went into and out of ice ages before humans and their dreaded SUVs.
That argument goes out the window if you are stuck pretending the earth is only a few thousand years old.
BTW, I think evoking Occam’s razor at this stage is premature.
That argument goes out the window if you are stuck pretending the earth is only a few thousand years old.
WOW
Your logic has sunk beneath your wisdom, like a stone.
If it was proven, beyond doubt, that it was 4 billion years old, whould it change yours?
You paint with the broad brush of hubris.
YES.
If it where also proven that evolution actually happened.
It would mean that objective morality did not exist.
It would mean that neither you nor I have free will.
It would, and has devalued human life.
And just so you understand, objective morality is that sense of right and wrong that everybody has, regardless of what they have been told.
Now, as a practical matter we have been living in your world for the past 150 years.
I do not accept that premise because I do not assume restrictions on the power of God. Because I do not start from that premise, I arrive at different conclusions.
Seriously ?
A proven, less than 10,000 year old earth would have no impact on how you viewed things ?
You are only left with two options.
Creation or Aliens.
[ BTW, I think evoking Occam’s razor at this stage is premature. ]
Depends on what you’re dividing...
dividing infinity (eternity) by anything gets a little silly.
Freedom of religion means that no one else can tell you what your religious beliefs must be. It also means you don’t get to tell anyone else what theirs must be.
So, you think comparative religion classes are a waste of time ?
What assumptions lead you to that conclusion?
Listen.
If you are actually sincere about exploring these issues, having an open mind and understanding of history will allow you to break on through to another side.
You can start with either:
http://www.amazon.com/Mere-Christianity-C-S-Lewis/dp/0060652926
best of luck to you.
You appear to have made the assumption that someone else can only have different religious belifs than you out of ignorance. Is that an accurate assesment?
Freedom of religion means that no one else can tell you what your religious beliefs must be. It also means you don’t get to tell anyone else what theirs must be.
It implies relativism.
That is the assumption that enforced my conclusion.
Yes.
Some religious beliefs are completely illogical, and many others have no historical foundation.
Still, there are those that are still seeking.
Do you find that assesment to be inaccurate?
If it is accurate, then do you disagree with the idea that we should have it, because it allows people to have incorrect religious beliefs?
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