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Radio Carbon Dating and Dendrochronology

18 May 2014

Tim Cullen continues with part two of his critique of C14 dating – go to http://malagabay.wordpress.com/2014/05/16/carbon-14-libbys-ring/ … which is something of an eye opener in some respects and is mainly a history of the method and how it became embedded in the mainstream as a means of upholding consensus dates and the like. We have of course published a raft of articles in SIS journals on radio carbon and other dating methods, mainly because the dates produced do not suit the scope of the various revised chronologies that have become popular at different points of time over the last 40 years. Yes, SIS has been going for 40 years – and this is the anniversary year.

Tim Cullen describes how it all started, the brain child of Willard Libby. It then describes how the methodology was gradually introduced and adopted by difference science disciplines. On page 8 he introduces dendrochronology where Willard Libby experienced problems. Fitting C14 to various mainstream dates seemed to work quite well but when it came to tree rings – it wasn't plain sailing. Libby was forced to accept a corrective curve based on dendrochronology – proposed by the dendrochronologists (and this is still the situation). This means the dendrochronologists tree ring data was seen as superior – but who was backchecking the tree ring construct. Was it a case of one scientist shouting louder than the other and getting their point of view accepted to the detriment of the other scientist (whose C14 methodology was viewed as slightly suspect as it could at times produce a variety of dates whereas tree rings were more precise). So, if there is an error in tree rings it has existed for many a long year – long prior to the Belfast dendrochronology that has published all its data for everyone to see.

As a result of the corrective curve, which supported consensus historical dates as worked out more labouriously by scholars using pen and paper, and all sides were happy – not sure about Libby however as he lost control of C14 and was sidelined. It was taken over by mainstream – and that is where it is now. As such, it is settled science – you are not allowed to think the unthinkable. Tim Cullen seems to imply the calibration curve was introduced because of the inability of tree rings to conform to Libby's raw C14 – nothing to do with C14 plateaus, or peaks and troughs. That is an added problem that modern researchers have found. Basically, Libby began with the assumption that C14 levels in the atmosphere were constant. The reality of plateaus reveals this is not so – but to what extent are tree rings more reliable, and how much compromise between the two methods was allowed in order to reach an acceptable base line. Tim Cullen, like many others, has pointed out that nowadays C14 is used to calibrate dendrochronology and dendrochronology is itself used to calibrate C14 (a sort of circular reasoning). Tim Cullen has further posts up his sleeve – to be published in due course.

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