Steve Austin Evolutionists believe that the oldest rocks on earth are meteorites. These ar

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Steve Austin Evolutionists believe that the oldest rocks on earth are meteorites. These are supposed to be left over from the original cloud (solar nebula) which condensed to form the sun, planets and meteorites. All normal earth rocks are thought to have had an igneous origin more than a billion years after meteorites formed. Because of this assumption, evolutionists believe that isotopic analyses of meteorites provide data from which to date the earth. Lead-lead isochron plots are the current way that evolutionists have estimated the age of the earth at 4.6 billion years. A simple discussion is found in Gunter Faure's book PRINCIPLES OF ISOTOPE GEOLOGY. The ratio of lead-207/lead-204 in meteorites is plotted against lead-206/lead-204 as shown below. ___________________________________ +| * | | * | | * | | * | LEAD-LEAD | * | ISOCHRON Pb-207/Pb-204 | * | PLOT | * | | * | | * | |* | 0|_________________________________| 0 + Pb-206/Pb-204 Each lead isotope ratio of each meteorite plots as a point on the graph. Together the points for meteorites describe a line as suggested on the above sketch. The line is called an "isochron" because all points on the line should have the same age. The slope of the line is supposed to be directly proportional to the age. A simple mathematical calculation using the slope of the line gives the age of the earth! Lead-204 is the common lead not formed from radioactive decay. It is supposed to have survived as the solar nebula condensed to form the earth. Lead-207 in meteorites forms from decay of uranium-235, and lead-206 forms from decay of uranium-238. Different meteorites have different concentrations of uranium. As time goes by, the ratios of radiogenic leads increase relative to the common lead giving the sloping line. The lead-lead isochron method assumes that the original nebula had uniform lead isotopic composition, and that the deviations from the initial composition have been caused by radioactive decay of uranium-235 and uranium-238 over the ages. There is also the assumption that the earth and meteorites formed at the same time from the same nebula. As a creationist I find these series of assumptions more than I can accept. I am even offended. Is there any compelling argument proving initial lead isotope uniformity? Could the meteorites have formed having different lead isotope ratios? Are we sure that there has been significant decay of uranium isotopes in these rocks? It seems that one has to buy an evolutionary cosmology before one can determine the age of the earth to be 4.6 billion years! I had hoped that the age of the earth would be a more straightforward calculation. I don't like speculative cosmology. Steven Austin, Ph.d Institute for Creation Research PO Box 2667 El Cajon, CA 92021 ========================================= Note: the author failed to understand the distinction of isochrons and psudo-isochrons, which yields his conclusions in error. Write to him and ask him to look at isochrons, not psudo-isochrons.


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