In June 1997 a large finger-sized piece of fossil wood was discovered in a Hawkesbury Sandstone slab just cut from the quarry face at Bundanoon.8 Though reddish-brown and hardened by petrifaction, the original character of the wood was still evident.
Identification of the genus is not certain, but more than likely it was the forked-frond seed-fern Dicroidium, well known from the Hawkesbury Sandstone.2,7 The fossil was probably the wood from the stem of a frond.Radiocarbon (14C) analysis
Because this fossil wood now appears impregnated with silica and hematite, it was uncertain whether any original organic carbon remained, especially since it is supposed to be 225–230 million years old.The laboratory staff were not told exactly where the fossil wood came from, or its supposed evolutionary age, to ensure there would be no resultant bias.
Nevertheless, a piece of the fossil wood was sent for radiocarbon (14C) analysis to Geochron Laboratories in Cambridge, Boston (USA), a reputable internationally-recognized commercial laboratory.
This laboratory uses the more sensitive accelerator mass spectrometry (AMS) technique, recognized as producing the most reliable radiocarbon results, even on minute quantities of carbon in samples.
The laboratory staff were not told exactly where the fossil wood came from, or its supposed evolutionary age, to ensure there would be no resultant bias. Following routine lab procedure, the sample (their lab code GX–23644) was treated first with hot dilute hydrochloric acid to remove any carbonates, and then with hot dilute caustic soda to remove any humic acids or other organic contaminants. After washing and drying, it was combusted to recover any carbon dioxide for the radiocarbon analysis.
The analytical report from the laboratory indicated detectable radiocarbon had been found in the fossil wood, yielding a supposed 14C ‘age’ of 33,720 ± 430 years BP (before present). This result had been ‘13C corrected’ by the lab staff, after they had obtained a d13CPDB value of –24.0‰.9
This value is consistent with the analyzed carbon in the fossil wood representing organic carbon from the original wood, and not from any contamination. Of course, if this fossil wood really were 225–230 million years old as is supposed, it should be impossible to obtain a finite radiocarbon age, because all detectable 14C should have decayed away in a fraction of that alleged time—a few tens of thousands of years.
Anticipating objections that the minute quantity of detected radiocarbon in this fossil wood might still be due to contamination, the question of contamination by recent microbial and fungal activity, long after the wood was buried, was raised with the staff at this, and another, radiocarbon laboratory. Both labs unhesitatingly replied that there would be no such contamination problem.
Just strikes me as pretty weird that everything carbon dated as young seems to fall into the range of about 30K or thereabouts, like with the list Blitzking provided for 30K dinos. It seems this highly correlating, concordant data is significant, especially when found in purportedly, "old" rock.