A Brief Review of Diffusion When radioactive isotopes decay in rock, various gases are produced as a byproduct.
Figure 1 clearly shows that his hypothesis was confirmed.It shows the conventional estimate for age as a function of the percent of argon released by heating experiments in the laboratory.The peak of 1160 Ma in Figure 2 shows that over “one billion years’ worth” of potassium-40 to argon-40 decay occurred RATE hypothesized that this decay occurred during several episodes of accelerated nuclear decay in the past, the more recent during the year of the Genesis Flood.However, they reported the laboratory results on all five samples.Figure 2 shows their “Age Spectrum” for one of their rejected samples (sample 5) collected from the hottest temperature at a depth of 15,000 feet below the surface.Figure 1 displays observed and theoretical diffusivities for helium as a function of temperature.
Note that temperature in degrees Celsius is hotter on the left side of the figure, so the diffusivity increases upward to the left.
The blue data from the laboratory experiments matched the green curve so well that Humphreys has said several times in his public lectures, “Never in my entire scientific career have I ever seen a numerical prediction verified so accurately.” Using the laboratory-measured diffusion rates, he was able to compute an estimated age of the earth and its uncertainties. The New Argon Results The deep Precambrian granite “basement” rock from the Fenton Hill GT-2 borehole contained not only zircons from which helium diffusion rates could be determined, but also a potassium-bearing microcline feldspar containing argon-40 that could be used to estimate age.
Harrison et al conducted argon-argon dating and diffusivity measurements on five feldspar samples.
In other words, the rate at which helium diffuses from the rock must be many times slower for the uniformitarian model in order to explain the concentration of helium observed in the rock today.
The RATE project obtained samples of granite from the Fenton Hill borehole and submitted them to one of the most widely respected helium laboratories for determination of helium diffusion rate as a function of temperature.
Introduction In the final report of ICR’s Radioisotopes and the Age of the Earth (RATE) project, Dr.