Links:
Introduction to this series
URL to the video
Please read the introductory blog to the series (linked above) first if you haven't yet done so to get the correct context for this blog.
This episode had quite a few time fillers. They went at length on the professional history of Dr. Humphreys and rehashed the "salt in the ocean" problem that he mentioned as evidence number 5 in the previous episode. I googled the issue a little and found that this problem has had a reply by Glenn Morton in 1996, way before his 2005 article in at icr.org which mentions this problem. Morton stated that a lot of output mechanisms for sodium have been overlooked in the 1990 Austin and Humphreys paper and that if those mechanisms are quantified and added to the mechanisms that were mentioned, the sodium input and output are within margins of error of each other. Without the error bars the sea should become less salty.
Like last time, I am incapable of lending merit to any one of the viewpoints, but Morton claimed in his open letter to Austin and Humphreys that the reflection was very quiet and I must say that I could not find a rebuttal on-line.
Still on the subject of sodium in the ocean, Dr. Humphreys goes at length on an anecdote of a young geochemist that showed confirmation bias and would not accept the creationists evidence on the salinity of the oceans but rather would rely on the opinion of the paleontologist Stephen J. Gould. Now isn't that the pot calling the cattle black? Humphreys is a champion of hand waving old-earth evidence (as will be made very clear shortly) or whole-sale ignoring evidence which contradicts his own world view. He dismissed the evidence for the origin of comets in the Kuiper belt and Oort cloud, he does not mention for a minute the cosmic microwave background and it's significance in the Big Bang model and he does not mention Mary Schweitzer, the original investigator of the T.rex blood cell remnants.
Finally he goes into the two subjects that he wanted to present. Carbon 14 showing a maximum age for old material and Helium leakage from zircon crystals. He starts with the notion that lots of matter like coal, wood, shells, bone, oil and CO2 contain C-14. With some of these, especially wood and CO2, I wonder why that is an issue, but I digress. He then states that the rebuttal to this is that even untainted diamond contains C-14. Now this is a claim worth looking at. If diamond, which formed during millions of years deep in the earth, would contain significant amounts of C-14, it would prove the diamond young because, as he clearly states in his presentation, C-14 has a half-life of only 5700 years so it is unsuitable for showing dates extending a few tens of thousands of years. I googled the subject and found that there is quite a bit of criticism that can be had on the process which was used to determine the C-14 content. The biggest giveaway was that diamonds that were not processed for dating showed a lower C-14 content than processed diamonds, a clear indication of contamination. As a side note, Humphreys says that the C-14 date is 58,000 years "conventionally", but if you correct for "wrong assumptions" the age is less than 10,000 years. What assumptions? How do you correct for them? If you want an example of hand waving evidence that Humphreys so much argues against, here you are.
What's more, Humphreys (and Austin for that matter) make a grave thinking error in presenting this evidence. It is not evidence for a maximum age of the earth, but for a minimum age. Let's grant, for the sake of argument, that the measured values are correct, then we have an extremely young piece of diamond and we should investigate how it would be possible to get such a young diamond through natural processes (the supernatural can't be proven scientifically but we do not exclude the possibility a priori). This, however, does not imply that the earth itself is young. Taylor and Southon use diamonds to measure instrument background radiation and get a C-14 rate comparable to the unprocessed diamonds by the RATE team (abstract at doi.org). Those diamond indicate a minimum age of several tens of thousands of years. One swallow does not a summer make.
Dr. Humpreys then goes on to another piece of evidence: helium leakage from zircon crystals. Zircon repels lead during its crystallization but does incorporate uranium. This decays to lead in a multi-step process and releases alpha particles (helium ions) during each step. This helium tends to leak out of the zircon with a rate that is dependent on the temperature. Humpreys made a graph and plotted two scenarios, the leak rate for the different temperatures given a 6000 year process and the leak rate given a 1.5 billion year process. His team also ordered an independent lab test for the leak rate of the helium given various temperatures and the plot for those leak rate lines up perfectly with the 6 Kyr process.
The first observation we need to make is that the data points are all in the higher temperature regions, to the right of the scale of the predictions with little overlap of the predicted values. One wonders if there is some data cherry picking going around here. It's worth mentioning here that (according to an evaluation of the RATE study) the zircon crystal samples have been taken at a depth of 750 m and 1490 m respectively, and both have associated temperatures that are below the range of what the lab study evaluated. I haven't seen the actual reports of either their zircon study or their lab test so I can hardly make an argument either way, but people who have make some reservations as to the scientific completeness of the study, especially regarding the lack of error bars and the lack of evaluating excess helium that seems to be common to the source region of the zircon crystals (see talkorigins.org).
The interesting part is that Dr. Humpreys acknowledges that the U-Pb dating of the same crystals show a 1.5 Gyr date. Once again, he employs some hand waving by saying that "God must have sped up the uranium decay during the past 6000 years". First, if the helium leak rates can be evidence that "God sped up the U-Pb decay", the reverse works just as well. We could just as well say that the U-Pb dating shows that "God must have slowed down the helium leaking during the past 1.5 billion years". His choice for the former is typical for starting with the answer and looking for confirming evidence while disregarding contrary evidence. But let's assume that God did speed up the U-Pb decay (and let's ignore that this would be contrary to the secular equilibrium that we see in intermediate daughter products), the sped up decay would equally increase the released energy for the decay and all oceans should be vaporized right now. The fact that they haven't shows that the 1.5 Gyr date is more likely than the 6 Kyr.
After the break there is nothing substantial in the episode, in fact it is just an advertisement for a few creationists' books on relevant subjects.
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