Polonium Halos in Primordial Rock Prove the Earth is Young

In the early 1970's Robert Gentry's published some information about Polonium halos in primordial granite. Since polonium has a half life of a few minutes, the results seemed to indicate an almost instant creation of primordial rocks. Such an interpretation would be incompatible with the relatively slow formation of the earth from a swirling cloud of dust and gas.

However, later work showed that Gentry made numerous errors about the geology of where the halos were found. In fact, Gentry's samples came from postmagmatic hydrothermal fluids that were deposited in dykes between the granite. In fact, Gentry had not even sampled the oldest rocks available (from the Superior Province of Archean age in northern Ontario) but had acquired his samples from the much younger Grenville Province. In addition to this, it appears that Gentry's halos were not from polonium, but most likely from other radioactive elements that have a longer half life. For all the details, check the link below, which was published in the May 1988 Issue of the Journal of Geological Education.

The Geology of Gentry's "Tiny Mystery"

Errors: faulty assumptions, faulty data

Last updated March 31, 2008


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