In just about every example that I've seen, the sample sizes are too small, or the error bars are too large, to justify such a conclusion. Some of them do not even attempt to measure anything at all, and some of them don't even get their facts straight about what the evidence consists of, let alone how it can or cannot be interpreted.

See here: https://howoldistheearth.wordpress.com/2018/01/29/answers-in-genesiss-ten-best-evidences-for-a-young-earth-summary-and-conclusion/

The mapping would have to be the same for every dating method that is used. Radiometric methods with different isotopes with different decay rates would have to change in lock-step both with each other and with non-radiometric methods such as continental drift, tree rings, ice cores, lake varves, stalactite and stalagmite growth, thermoluminescence, racemisation, sedimentation, and a whole lot more. Furthermore, they would have to change in lock-step with each other by a factor of many millions.

Given the number of different methods involved, and the scale of the acceleration required, such a scenario is not even remotely plausible.

Presuppositions or not, whichever interpretive framework you use has to stick to certain rules. Rules that have nothing whatsoever to do with "naturalism" or "uniformitarianism" but that are simply the basic principles of accurate and honest weights and measurements. In fact, that is what the Bible itself demands:

13 Do not have two differing weights in your bag—one heavy, one light. 14 Do not have two differing measures in your house—one large, one small. 15 You must have accurate and honest weights and measures, so that you may live long in the land the Lord your God is giving you. 16 For the Lord your God detests anyone who does these things, anyone who deals dishonestly. — Deuteronomy 25:13-16

These verses are not ones that you can fob off as being taken out of context. Not having accurate and honest weights and measures is lying in every context, and insisting that these verses only apply to buying and selling is effectively demanding the right to tell lies. Accordingly any creation model, any interpretation of Genesis 1-11, any attempt to challenge the scientific consensus on the age of the earth or evolution, must obey those verses. Anything that does not is not scientific, is not Biblical, and is not honest.

This claim that "uniformitarianism" is a mere assumption is completely untrue. There are numerous ways that scientists can determine which rates were uniform across space and time, and which were not. This can be done, for example, by determining rates using different methods whose assumptions are independent of each other. If these methods give the same results (as happens the majority of the time), that is a pretty strong indication that the assumptions involved are, in fact, correct.

See, for example, the cross-checks between radiometric dating in the Hawaiian islands and direct GPS measurements of continental drift.

And no, you can't just fob those off as "both making the same assumptions of uniformitarianism." The fact that they give the same results is a test of assumptions, and tests of assumptions are not assumptions themselves.

In order to dismiss these cross-checks as "just an assumption," you would have to provide a plausible explanation as to how both rates could have changed by a factor of many millions while remaining in complete lock-step with each other. The more such cross-checks that we have, the greater the number of rates that will have to change in this way.

The 6,000 year figure came from a technique that was far more immature and far more complex than U-Pb concordia diagrams, with far more sensitivity to factors such as pressure. This means that there was much more scope for errors and fudging to creep in, and it could not be considered anywhere near as reliable, even if conducted by independent, third-party labs. The uncertainty in the 6,000 year figure quoted by the RATE team was ±2,000 years or 33%. That itself is far larger than the uncertainties in mainstream radiometric dating techniques, which can be as tight as ±1% or less (and in some cases as tight as one part in several thousand).

Furthermore, the RATE team's study was riddled with numerous procedural and mathematical errors, some of which were very serious. (Henke, 2010.)

Sorry, but accelerated nuclear decay is science fiction, especially on the scale required to squeeze the evidence into a young earth. The YECs' own RATE project team themselves admitted that the heat released by that amount of decay in that short a time would have raised the temperature of the earth to 22,400°C (Source: RATE project report, page 183.) No satisfactory explanation has ever been provided as to where the heat would have gone.

Just how big are the doubts you are referring to here? One of the most fundamental rules of experimental science is that doubts over a technique's robustness must be quantified. That is what error bars are about.

Not large enough to reduce the age from 4.5 billion down to six thousand. For that, the amount of lead in the zircons would have to be the same as the amount of uranium.

Zircons are small and would crystallise quickly in the laboratory. Thus the laboratory conditions under which they form would be much closer to the YEC scenario being proposed here than the one they dismiss as "uniformitarian assumptions." And it is under this rapid formation scenario that the concentration of lead in zircons is measured at close to zero.

Zircons can contain up to about 1% uranium when they first form but their lead content is measured at no more than a few parts per trillion. (Gehrels, 2010)

The full article is here:

• https://www.nature.com/articles/ncomms1659

I would like to know why CMI have not linked directly to this article from the body of the text (or even from the footnote). Given that young Earth creationist organisations are (rightly or wrongly) frequently accused of quote mining, they should be doing everything in their power to dispel such a perception. The correct way to do this is to provide easily accessible hyperlinks in the body of their articles directly to their original sources.

Again, the chemical and crystallographic properties of zircons -- an issue that this article does not address.

Besides, even if the dates are potentially wrong as the article suggests, they still give a lower limit. If the Earth were only six thousand years old, we should never find zircon crystals containing more than about eighteen parts of lead per billion.

Sorry, but that is to suggest that natural laws have changed. Changes to nuclear decay rates would have required changes to the fundamental constants of nature.

Furthermore, the young Earth organisations have themselves admitted that accelerated nuclear decay rates on the scale that they require would have raised the temperature of the Earth to 22,000°C.

Again, that is science fiction.

The starting conditions are not just a "secular" assumption; they are a direct consequence of the chemical and crystallographic properties of zircon crystals themselves. Uranium has the right valency and atomic radius to fit into their crystalline structure. Lead does not. For zircon crystals to have formed containing lead, the chemical properties of the elements themselves would have to have been different in the past. That is science fiction.

There is something very important that Answers in Genesis is not telling you here.

Geochronologists know this.

Modern uranium-lead dating methods have ways of taking into account the possibility that the lead atoms might have moved.

First of all, when lead atoms move, they will be expelled from the zircon crystals; however, the parent uranium will not. This means that even when U-Pb ages are inaccurate, they will still give a lower limit.

Secondly, there are ways of testing to see whether a zircon crystal has been disturbed in this way. Because uranium has two different isotopes that decay to different isotopes of lead with different decay rates, researchers can use any discrepancies to figure out when the leakage occurred. This is done using a concordia diagram.

Answers in Genesis is claiming here that radiometric dating makes assumptions that it does not, and that the assumptions that it does make can not be tested when in fact they can.

This is not just a "cry" either. This fact is used by physicists to predict where to find sources of hydrocarbons that do not contain any carbon-14. They need to do this in order to be able to detect solar neutrinos.

See http://www.talkorigins.org/faqs/c14.html

The fact that there is a measurable correlation between nearby uranium deposits and measured levels of carbon-14 is a strong indication that the uranium radiation hypothesis is in fact the correct one.

This is not true. Several possible sources of contamination can be identified for AMS instrument background:

• ion source “memory” of previous samples, due to radiocarbon sticking to the walls of the ion source, thermally desorbing, and then sticking to another sample
• mass spectrometer background, non-radiocarbon ions that are misidentified as radiocarbon, sometimes through unexpected mechanisms
• detector background, including cosmic rays and electronics noise

See http://www.talkorigins.org/faqs/rate-critique.html

This will not rid samples of all contamination. It may remove surface contaminants, but it will not remove contamination that has already made its way right through the sample. Nor will it remove contamination that is introduced through sample preparation processing, for example.

Contamination introduced through sample processing can actually be measured. This can be done by repeating some of the steps of sample preparation a second time and measuring the difference. The amount of contamination introduced in sample preparation has been found to be between 0.14% and 0.25% modern carbon for each step.

See http://www.talkorigins.org/faqs/rate-critique.html

Contamination is NOT a "rescuing device"; it is a systematic error. Accounting for sources of error such as contamination is a standard practice in every area of science. To dismiss sources of error such as contamination as "rescuing devices" or "hackneyed defences" in this manner is to encourage Christians to adopt a sloppy and indisciplined approach to science which, in any other area of scientific inquiry, would kill people.

An explanation is needed as to why this photograph has people in it in front of the parts of the rock in which fractures are clearly visible in other photographs of the formation elsewhere.

For clearer photographs of this rock formation, see here:

https://answersingenesis.org/blogs/ken-ham/2017/09/05/geologist-collects-grand-canyon-rocks-for-unprecedented-study/

This rock formation can also be seen on Google Maps (together with a 360° photo) here:

https://www.google.co.uk/maps/@36.1544785,-111.8301097,3a,18.3y,137.32h,106.21t/data=!3m8!1e1!3m6!1sAF1QipMbE54f2LdHeLPKUMufZhCD9Ap_CAn-RvtZSyJ9!2e10!3e11!6shttps:%2F%2Flh5.googleusercontent.com%2Fp%2FAF1QipMbE54f2LdHeLPKUMufZhCD9Ap_CAn-RvtZSyJ9%3Dw203-h100-k-no-pi0-ya340.3791-ro-0-fo100!7i8704!8i4352?dcr=0

These photographs clearly show that, contradictory to what is claimed here, these rock formations are fractured.

[citation needed]

Source: Millman & Syvitski (1992). This is an estimate for rates over the past 2,500 years or so and is not representative of historic rates before widespread farming and deforestation. It is also a very rough estimate with huge error bars, and later in the paper they say that the final value is ultimately unknown.

Willenbring et al (2014) give a much lower long-term estimate of 5.5 billion tons per annum.

It should be noted that this sediment mostly gets deposited on the continental shelf (e.g. the mouths of rivers).

This calculation is not valid. The sediment estimated by Millman & Syvitski is deposited on the continental shelf, while Hay et al's figure refers to the deep ocean floor.

"¹³Do not have two differing weights in your bag — one heavy, one light. ¹⁴Do not have two differing measures in your house — one large, one small. ¹⁵You must have accurate and honest weights and measures, so that you may live long in the land the Lᴏʀᴅ your God is giving you. ¹⁶For the Lᴏʀᴅ your God detests anyone who does these things, anyone who deals dishonestly." — Deuteronomy 25:13-16

Source: Hay et al (1998). This only refers to deep ocean sediment and not to deposits on the continental shelf.