What's the creationists thought on this?

Although it's been pretty beaten to death already, a few items:Woodmorappe did not look at 500 papers, he selected 350 dates from a lot fewer than 350 papers. He did not give any indication of how many dates he reviewed to select those 350, so a meaningful statistical analysis is impossible. His claim to have found "Over 300 serious discrepancies..." is laughable. I've read the original paper, and the majority of his "serious discrepancies" are not that at all, they're well-explained and well-understood. Steven H. Schimmrich wrote a critique at TalkOrigins, Geochronology kata John Woodmorappe, which is easily understood by the non-geologist and explains several of the "discrepancies". he concluded that Woodmarappe made many serious errors:

• Selective quotations from the scientific literature
• The presentation of data devoid of any geological context
• Ignoring well-known limitations of dating methods
• The use of a "shotgun" approach
• The inclusion of obsolete data
• The use of a small data set to reach sweeping conclusions
• The lack of an appropriate audience

Glenn Morton plotted Woodmorrappe's dataset at Young-Earth Arguments: A Second Look. measured age against expected age. There's a lot of scatter, as you'd expect when the criterion for data selection is the existence of scatter, but the trend is clear: Chuck77, it would do you good to reflect on the reliability of your sources.Woodmorappe's paper is not online, but I have a PDF of it if anyone wants to read it.

Yeah, that's because it's pictures of the document with OCR'd and selectable text lurking behind the pictures. That's how Acrobat handles scanned documents. Yes, as detailed at the links I already gave. Creation "science" is composed of lies and nothing else. Believe what you wish for whatever reasons make sense to you, but when you start claiming scientific respectability you're in an arena with particular ways of investigation, and creation "science" has consistently failed in that arena.Number of refrerences doesn't mean much. Intellectual honesty and integrity, weight of evidence, logical thought… they count.Edited by JonF, : No reason given.

Actually, what he refers to does not involve 14C dating but does involve carbon, and is very interesting. The researchers looked at carbon particles found in metamorphic rock that is 3.8 to 4.2 billion years old. These particles have an isotopic composition and structure that indicate the presence of life, and are often cited as evidence for life on Earth being 3.8 to 4.2 billion years old. However, these researchers applied new techniques:

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The new approach relies upon a variety of microscopy and spectroscopy methods to characterize intact micro-fabricated cross-sections of crystalline graphite removed from the rock samples.

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They concluded that the carbon particles are younger than the rock:

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"The characteristics of the poorly crystalline graphite within the samples are not consistent with the metamorphic history of the rock," said Boston College Assistant Professor of Earth and Environmental Sciences Dominic Papineau, a co-author of the report. "The carbon in the graphite is not as old as the rock. That can only ring a bell and require us to ask if we need to reconsider earlier studies."

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I don't know the details, I can't access the primary source. But it's totally irrelevant to 14C dating, as you knew, but as Mazzy should have known but didn't.

As a rule of thumb, precision of a couple of percent is a reasonable result in most dating systems. U-Th-Pb dating systems can achieve sub-1% accuracy, mostly because the half-lives are known more precisely than for other isotopes (bombs and reactors, ya know).See Neodymium-142 Evidence for Hadean Mafic Crust (free registration required). The rocks involved are constrained by the geological setting to be older than rocks that date to 3817 ± 16 My from U-Pb discordia dating, a claimed precision of about 0.4%. The rocks themselves were dated using Sm-Nd isochrons at 3819 ± 270 My and another set were dated at 3840 ± 280 My, both about 7% error. That's fairly high uncertainty, but these rocks have been through a lot and it's difficult to extract the information.See Earliest Evidence of Life for a brief explanation of why these carbon particles are thought to be evidence of life. That article was published at about the same time as Neodymium-142 Evidence for Hadean Mafic Crust, and does not take those findings into account.Edited by JonF, : No reason given.Edited by JonF, : No reason given.