Research Communications NETWORK BREAKTHROUGH REPORT February 10, 1977

Glossary of Technical Terms A parent radioactive atom decays into a daughter atom in various ways, one of which is by the emission of an alpha particle from the parent atom's nucleus. Numerous types of radioactive atoms occur in nature, but only three are the initiators of a decay series: uranium-238 (238U); uranium-235 (235 U); and thorium-232 (232Th). (The numerical superscript signifies how heavy the element is. Isotopes of the same element have different weights but nearly identical chemical behavior—as for example (238U) and (235U). An alpha particle has a weight of 4.) Each of the three decay-series initiators decays, by a chain of steps, into lead. For example, the alpha-decay steps in the 238U series are the following (steps not involving alpha-decay are not shown here): 238U    →   234Th         232Rn   →   218Po 234U    →   230Th 218Po   →   214Pb 230Th   →   226Ra 214Po   →   210Pb 226Ra   →   222Rn 210Po   →   206Pb Similarly, 235U decays by a different series of steps to 207Pb, and 232Th decays to 208Pb. Note that while all the series end up with lead, each one results in a different isotope of lead. The half-life of a given type of radioactive atom is the time during which half the atoms in any collection will decay. The half-life of 238U is 4½ billion years. Half-life, decay rate, and decay constant are closely related quantities. If we assume that the decay rate has not changed over geologic time,* and if we measure 1) how much of a parent in a rock has decayed into its daughter; and 2) the current rate of this decay, then we can, it is generally believed, assess the date when the parent was incorporated into the rock—that is, the date when the rock was formed. In the case of Earth's oldest rocks, this date (some 3½ billion years ago) is thought to be the time when the molten Earth first cooled down sufficiently for rocks to solidify from the primordial magma. *Numerous other assumptions and technicalities also come into play.

[This review is based upon a series of telephone interviews with Robert V. Gentry, as well as the available technical literature.]

• Current physical laws may not have governed the past.
• Earth's primordial crustal rocks, rather than cooling and solidifying over millions or billions of years, crystallized almost instantaneously.
• Some geological formations thought to be one hundred million years old are in reality only several thousand years old.

Grant these propositions and—any researcher will tell you—the entire structure of the historical natural sciences would dissolve into formlessness. Few certainties would remain. Yet these very possibilities (and others equally disintegrative) have been suggested in a remarkable series of papers published over the past several years in the world's foremost scientific journals—Nature, Science, and Annual Review of Nuclear Science, among others. Nor has this assault upon orthodoxy elicited a vigorous counterattack: the research results published to date have been so cautiously and capably elaborated, and evidence so thoroughly piled upon evidence, as to forestall any outcry by those whose scientific sensibility may have been outraged. While some investigators appear finally to be arming themselves for combat, the issue has not yet been joined.

It was over a decade ago that Robert V. Gentry, puzzling over questions about the Earth's age, directed his attention to an obscure and neglected class of minute discolorations in certain minerals. He has since examined more than 100,000 of these "radiohalos," and without doubt stands as the world's leading authority on the subject. As an assistant professor of physics at Columbia Union College (Takoma Park, Maryland), he has brought to bear upon the halos an array of sophisticated instrumentation such as few researchers ever have the privilege to wield. As a result, he has converted the entire field of radiohalo research into an exact science, transmuting the microscopic spheres of mystery into rich mines of exciting and challenging information.

RADIOACTIVE HALO (or RADIOHALO): "In some thin samples of certain minerals, notably mica, there can be observed tiny aureoles of discoloration which, on microscopic examination, prove to be concentric dark and light circles with diameters between about 10 and 40μm [a lone micrometer is one-millionth of a meter] and centered on a tiny inclusion. The origin of these halos (first reported between 1880 and 1890) was a mystery until the discovery of radioactivity and its powers of coloration; in 1907 Joly and Mugge independently suggested that the central inclusion was radioactive and that the alpha-emissions from it produced the concentric shells of coloration. . . . halos command attention because they are an integral record of radioactive decay in minerals that constitute the most ancient rocks" (1).

Gentry's studies have led him to the following conclusions:

1. Some halos ("polonium" halos) imply a nearly instantaneous crystallization of Earth's primordial rocks: and this crystallization must have occurred simultaneously with the synthesis/creation of certain elements.
2. Some halos correspond to types of radioactivity which are unknown today.
3. Whereas radiohalos have been thought to afford the strongest evidence for unchanging radioactive decay rates [p. 235] throughout geological time (and these rates enable scientists to determine rock ages), in actuality the overall evidence from halos requires us to question the entire radioactive dating procedure: something appears to have disrupted the radioactive clocks in the past.
4. Halos in coal-bearing formations that are conventionally thought to be 100 to 200 million years old suggest these strata to be only several thousand years old. Further, the time required for coal formation is much less than previously thought.
5. Taken together, these conclusions point to one or more great "singularities" in Earth's past—events or processes that are discontinuous with the rest of history, unique occurrences that critically affect the data we now have. If we attempt to interpret these data solely in terms of current processes, we go astray.

In this report we will discuss only those researches leading to conclusion (1), reserving the rest for a subsequent report.