Claim CF201:
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
that 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 radio-haloes occur
took millions of years to form. All of the original polonium should have
decayed in that time. Thus polonium radio-haloes indicate a sudden
creation of polonium in rock.
Source:
Gentry, R. V., 1986. Creation's Tiny Mystery. Knoxville, TN: Earth
Science Associates.
Snelling, A. A., 2000. Polonium radiohaloes: Still "a very tiny
mystery". Impact 326 (Aug.), i-iv.
Response:
- 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 polonium haloes 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 (Brawley 1992; Wakefield 1998).
- The biotite in which Gentry (1986) 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 that intruded a paragneiss
that 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 (Wakefield 1998).
- Stromatolites are found in rocks intruded by (and therefore older than)
the dikes from which Gentry's samples came, showing that living things
existed before the rocks that Gentry claimed were primordial (Wakefield
1998).
Links:
Brawley, John. 1992. Evolution's tiny violences: The Po-halo mystery.
http://www.talkorigins.org/faqs/po-halos/violences.html
References:
- Brawley, J. 1992. See above.
- Gentry, R. V. 1988. Creation's Tiny Mystery. Knoxville, TN: Earth
Science Associates.
- Wakefield, J. R. 1998. See below.
Further Reading:
Wakefield, J. Richard. 1998. The geology of Gentry's "tiny mystery".
Journal of Geological Education 36 (May): 161-175.
http://www.csun.edu/~vcgeo005/gentry/tiny.htm
Collins, Lorence G. 1997. Polonium halos and myrmekite in pegmatite and
granite. http://www.csun.edu/~vcgeo005/revised8.htm
created 2001-3-31, modified 2003-9-11
