Skinwalker and Invert Nexus:
I've read through the posted web-sites, and though they hint at the creation of the non-intrinsic C-14, surprisingly (to me, anyway), they do not discuss the actual method, other than to allude to alpha activity from the U/Th that is well-recognized to be present either in the carbon-bearing material, or the surrounding rock matrix.
As I noted on the first page of this thread, I believe it takes more than just the alpha particle striking, for example, a C-12 nucleus, to create the C-14 (And yes, the alpha daughters of the U/Th series are of sufficiently high energy, up to 6 MeV and higher, to penetrate the repulsive coulomb barrier of low-Z materials such as Be, B and C).
As I noted earlier in this thread, long before nuclear reactors were invented/created, nuclear scientists created neutrons in the form of a "neutron howitzer" which was a mixture of Radium-226 powder (4.78 MeV alpha) mixed with Beryllium-9 (100% of natural Be) powder, inside a 'shielding' that had one end open to emit the neutrons. The alpha-on-beryllium nuclear reaction is well-known, and currently used inside of nuclear reactors to insure the presence of some neutrons to initiate the chain reaction (following shut-down, or on start-up of new fuel), as well as inside of nuclear bombs, again to insure the presence of some neutrons to initiate an uncontrolled chain reaction. CRC Handbook reports 30 neutrons produced per 1,000,000 alphas striking the metal (most simply stop in the matrix of electrons, a few actually will hit the nucleus).
While it is well known that U/TH are present in copious abundance in fossil carbon, and fossil carbonates, from which some samples produce a small amount of C-14 that cannot be accounted for by un-decayed organic C-14, what has NOT been reported in any of those articles is the abundance of Beryllium. It would appear that the low neutron flux that would be present in any sample of material containing U/Th and its 30 radioadaughters (all of which are in radioactive equilibrium with the parent U/Th atoms) would be controlled by the relative amount of Be present. It would be interesting to see if the amount of C-14 directly correlates with the amount of Be present in the surrounding rock, coupled with the amount of U/TH present in the surrounding rock.
Beryllium is found in abundance in some 30 minerals, and of course in lesser abundance elsewhere on the Earth's surface. It's current price is about $5/gram (CRC Handbook), and it has found wide-spread usage in many industries (CRC Handbook)
Of course, once there is a low-neutron-flux presence (from the alpha-on-beryllium reaction), it becomes a simple matter for the neutrons to be moderated by the carbon matrix, and absorbed by the naturally present C-13 nucleus (1.1% natural abundance), forming small amounts of C-14, which would remain for long periods of time due to the relatively long half-life.
Of course, Ice Age doesn't want to look for explanations - he just likes the attention he draws to himself; good, bad, or indifferent.
In any event, what I find interesting about this particular thread is that it points up another source of potential error for C-14 dating; namely the relative amounts of U/TH present and the relative amounts of Be present, that can skew results somewhat. I do believe that that partiuclar potential source for error has not been well-detailed in the literature, and deserves further investigation as to how pervasive it might be. It appears, however, that it would only become a factor in very aged materials on the order of 20,000 years old and older.
The fact that there exists a very plausible expanation for the presence of small amounts of C-14 in well-aged carbon-bearing materials likely does not sit well with those who are looking for something, anything, that would support their "young earth" views. The fact that they ignore the mountain of evidence to the contrary shows they are not interested in science, logic or reasoning.