Paul Giem: Isochron Dating Rocks and Magma Mixing

[Dan_Eastwood]

With discussion of carbon dating here, this new thread may be of interest.

Radiocarbon in Coal?

Several years ago, the creationist RATE Team obtained multiple coal samples from different coal seams all over the US and submitted them to the now closed Canadian IsoTrace Facility for radiocarbon dating. Interestingly, the measured 14C activity of those coals was quite high compared to the laboratory’s ‘standard’ background, ranging from 0.10±0.03 to 0.46±0.03 percent Modern Carbon. Humphreys et al. (2011) believe this contradicts the notion that coal fields are millions of years old: »How does one make sense of these 14C measurements that yield a uniformitarian ages of 40,000–60,000 years for organic samples, such as our coal samples, that have uniformitarian ages of 40–350 million years based on long half-life isotope methods applied to surrounding host rocks? Clearly there is an inconsistency.« As it turns out, creationists are not the first to discover this problem. Scientists have known about this for decades. For instance, Vogel, Nelson and Southon (1987) used coal as backg…