To: All Rcvd: NO Re: Nonequilibrium Radiocarbo Status: Public I got the following info fro

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From: King Of All Crackpots Sent: 04-27-94 15:35 To: All Rcvd: -NO- Re: Nonequilibrium Radiocarbo Status: Public ------------------------------------------------------------------------ I got the following info from an article by Robert L. Whitelaw. [1] Definitions SPR: Specific Production Rate of C-14 atoms in the earth's atmosphere by cosmic radiation in atoms per min. per gram of total carbon in the earth's active carbon inventory. This total inventory is defined as all carbon in the cycle from atmospheric CO^2 to living things and back again. SDR: Specific Decay Rate of C-14 atoms in any specimin of a living or once living thing in atoms per min. per gram of total carbon in the specimin. For living things on earth today, this is approximately equal to 16 disintigrations per min per gram of total carbon which corresponds roughly to 1.4 atoms of C-14 per trillion atoms of total C. The Radiocarbon Dating Method 1) Cosmic radiation bombards the atmosphere with energetic particles of 1 to 2 BeV. 2) Neutrons of 5 to 10 MeV are generated 3) Two reactions take place after the neutrons are slowed down 14 14 1 N + n => C + H 98% of reactions of neutrons of 0.4-1.6 MeV 14 12 3 N + n => C + H Remaining reactions 4) C-14 oxidizes to form CO and diffuses to produce a fairly uniform 2 14 12 C /C oxide ratio 2 5) The average neutron intensity is 2.6 n/cm -sec 2 6) The know carbon inventory in g/cm (7.25 in ocean carbonates, 0.59 in dissolved ocean organics. 0.33 in the biosphere, 0.12 in the atmosphere) yeilds a value for SPR of (2.6)(60)/8.3=18.8 atoms/g-min 7) SDR is 16.1 + 0.5 dis/g-min based on the 1950 half-life of 5568 yrs - (Libby's original paper appeared in 1952). If the world was billions of years old, the SDR should have long since come into equilibrium with the SPR 8) Libby assumed the two numbers equal. He later corrected the 16.1 figure to account for the C-13/C-12 ratio. The new value was 15.3 In the noneqilibrium method od radiocarbon dating, it is not assumed that the SPR and SDR are equal. It, instead, assumes an exponential buildup for SDR starting from zero at creation. Robert H. Brown has derived a formula for converting "radiocarbon time" to real time [2]. -2.211(5.35 - T) -1 R = T + 8.3 [ln(1-0.989e ) ] where R is the radiocarbon date in thousands of years and T is the real time before present (present = 1950) in thousands of years. Unfortunately he doesn't give a complete derivation of the formula. He gives an equation that must be calibrated to the Bible. But there's no explanation for where this equation came from. Some examples of the conversion follow: T R 0 0 3100 3160 3700 3920 4300 5150 4900 8680 5250 18320 5350 42780 This method is apparently specific to the C-14 dating method so it would have no direct effect on geologic dating. And, of course, if you don't accept the Bible [as factual], then you don't accept the calibration. References CRSQ-Creation Research Society Quarterly [1] Robert L Whitelaw CRSQ March 1993 pg 170-183. Note: This article is really just an overview of various creationist papers on radiocarbon dating. [2] Robert H Brown CRSQ June 1992 pg 45-47. -- Ray Cote


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