Polonium halos indicate a young earth (Talk.Origins)
- Some micas in granite have tiny haloes caused by the decay of radioactive elements. From their diameters, we know the energy of the alpha particles which caused the haloes, which tells us what element decayed. Some of these haloes formed from isotopes of polonium, all of which have short half-lives (138 days for the longest-lived isotope). According to conventional geology, the rocks in which the polonium radiohalos occur took millions of years to form. All of the original polonium should have decayed in that time. Thus polonium radiohalos indicate a sudden creation of polonium in rock.
- Gentry, R. V., 1986. Creation's Tiny Mystery. Knoxville, TN: Earth Science Associates.
- Snelling, A. A., 2000. Polonium Radiohalos: Still "A Very Tiny Mystery". Impact 326 (Aug.), i-iv.
CreationWiki response: (Talk Origins quotes in blue)
1. Polonium forms from the alpha decay of radon, which is one of the decay products of uranium. Since radon is a gas, it can migrate through small cracks in the minerals. The fact that Po-halos are found only associated with uranium (the parent mineral for producing radon) supports this conclusion, as does the fact that such haloes are commonly found along cracks.
The fact that all three forms of Polonium are part of the uranium decay chain and that the haloes are only found in association with uranium has caused some creationists to question Gentry's conclusion. However only 210Po haloes are found along such cracks. 210Po has longest half life (138 days) of the Po isotopes involved in these haloes.
2. The biotite in which Gentry obtained some of his samples (Fission Mine and Silver Crater locations) was not from granite, but from a calcite dike. The biotite formed metamorphically as minerals in the walls of the dike migrated into the calcite. Biotite from the Faraday Mine came from a granite pegmatite which intruded a paragneiss which formed from highly metamorphosed sediments. Thus all of the locations Gentry examined show evidence of an extensive history predating the formation of the micas; they show an appearance of age older than the three minutes his polonium halo theory allows. It is possible God created this appearance of age, but that reduces Gentry's argument to the omphalos argument, for which evidence is irrelevant.
While Talk Origins may have a point here, it needs to be noted the alleged evidence for extensive history assumes uniformitarian geology. Because of this fact, this response adds up to: Your theory doesn't work under my theory, so your theory is wrong.
3. Stromatolites are found in rocks intruded by (and therefore older than) the dikes which Gentry's samples came from, showing that living things existed before the rocks which Gentry claims are primordial.
There is evidence that some stromatolite-like structures are abiological in origin, as such their presence would be irrelevant.
ICR is researching Po-haloes, including the possibility of their formation in rock formed during the Flood. In such cases they would be considered to have come from the uranium decay chain, but quickly removed from the uranium. The rock would still show evidence of rapid solidification. This possibility satisfies all three of Talk.Origins' responses. Researchers at ICR are just following the data to see where it leads.
- Snelling, Baumgardner, Vardiman 2003 .ABUNDANT PO RADIOHALOS IN PHANEROZOIC GRANITES AND TIMESCALE IMPLICATIONS FOR THEIR FORMATION. - Eos, Transactions of the American Geophysical Union.