A much better question is, what the flying fck does C14 in fossil hydrocarbons have to do with the age of the Earth, and life?Neither life, nor the Earth, is dated by the C14 content of fossil hydrocarbons.Even if you want to try do date fossil hydrocarbons by it's apparent age through it's C14 content, you still get >150K year dates (some of the purest samples give (IIRC) ~190K year apparent dates due to the low but still continously produced C14), which is still 25-30 times older than Sal thinks the entire universe is.None of this obsession with C14 in coal or other fossil hydrocarbons has ANY bearing on the actual age of the Earth, or for how much of that age life has existed on it.
AbstractTo examine one component of the instrument-based background in the University of California Keck Carbon Cycle AMS spectrom-eter, we have obtained measurements on a set of natural diamonds pressed into sample holders. Natural diamond samples (N = 14) fromdiﬀerent sources within rock formations with geological ages greatly in excess of 100 Ma yielded a range of currents (110-250 lA 12C where ﬁlamentous graphite typically yields 150 lA 12) and apparent 14C ages (64.9 ± 0.4 ka BP [0.00031 ± 0.00002 fm] to80.0 ± 1.1 ka BP [0.00005 ± 0.00001 fm]). Six fragments cut from a single diamond exhibited essentially identical 14 C values - 69.3 ± 0.5 ka-70.6 ± 0.5 ka BP. The oldest 14C age equivalents were measured on natural diamonds which exhibited the highest currentyields.
Many (super 14) C dating laboratories have established that coal samples exhibit a finite (super 14) C age, apparently caused by contamination of the specimens before any laboratory preparation is undertaken.He then points out the contamination cannot be due to radioactive decay of other products:Because coal is formed over geological time scales at depths providing excellent shielding from cosmic rays, its 14C content should be insignificant in comparison to the 14C introduced by even the most careful sample preparation techniques used in 14C dating laboratories. How is it then, that a material, which should show a14C age indistinguishable from that produced by a combination of machine background and contamination during careful sample preparation, routinely produces a finite 14C age?One suggestion is that radium, which is present in some coals at the sub pm level, as a decay product of the uranium/thorium series, may produce 4C during an extremely rare decay event (Rose & Jones, 1984). Jull,Barker and Donahue (1987) have detected 14C from this process in uranium/ thorium ores. Blendowski, Fliessbach and Walliser (1987) however, have shown that the 14( decay mode of 226Ra is only of the order of 10-11 of the preferred a decay channel to 222Rn. Thus, the amount of 14C produced by such events derived from radium in coal must be considered as insignificant.