Posted on 04/11/2014 9:38:33 AM PDT by SunkenCiv
Did they find my guns by it? I am pretty sure this was the same area of my tragic boating accident...
Right, the RC dating shows the oldest possible date, which is the youngest ring; if the bark is present (possible, but unlikely), the date of the cutting can be found. But this is a hollowed out log; the only missing layer is likely to be the last one, so, they know when it was cut. :’)
So the carbon dating varies from sections of the tree, from inner to outer, to the bark, is that correct?
It’s called radiocarbon dendrochronology. Dendrochronology as a technique began before radiocarbon dating, but only yielded relative dates, and they were (as you might imagine) a little subjective. The technique began in the SW US where there are timbers in precolumbian structures that can have their ring spans counted (for the age) and measured (for comparison with other samples of the same species).
Radiocarbon dating used to use a lot more of the sample, so it was used sparingly; as technology improved, IOW, by about 1970, it was possible to get a more accurate date with much smaller samples, making radiocarbon dating of each ring practical. Before this, a log might be cross-sectioned, and the slice dated, yielding an average date, which works adequately because the rings could be counted beforehand.
Dating individual rings turned up the infomrmation that the RC quantity in the atmosphere varies from year to year; that in turn made dendrochronology more important, since the sequence of fluctuating values can be “wiggle-matched” to build a ring sequence beginning with living specimens, and going back to overlapping sequences in dead samples, then overlapping those with older samples, to build a continuous sequence that can be cross-checked by other labs using second samples from the same specimens.
Nah, your guns and your canoe were seized by the Bureau of Firewater, Canoes, and Thundersticks.
Wow, even I felt a little offended by that one.
A little high-quality marine wax and she’ll be good as new.
Duct tape would be good, too.
Generally people build things out of freshly cut wood. They might have even taken advantage of a fallen log that was one or two years old, but after that the logs tend to rot. So the reasonable assumption is that this was carved within a short time frame of when the tree died.
That much I understood but where I was uncertain was getting different carbon dates for different parts of the tree. I assumed the item would give one date overall. I’m still not sure if I’m right about that but if so then it makes sense.
Ahhhh... well in that case the younger date could have come from fungus or spores that may have grown on the old log if it became partially exposed at some point or an air pocket became trapped under it. The growth would have died away a long time ago but left biological material causing C-14 ratio-contamination between cracks in the much older log — that’s just one example.
You can’t bow fish for carp in Lake Minnetonka because it is a designated muskie Lake.
Purified by outboard engine smoke, oil, and Urasian Water Milfoil.
So, the northern Native Americans’ technological high-water mark was reached about 1,000 years ago...since then even their latest advance, the casino, has only been an adaptation of a European invention.
Expired registration sticker, ID numbers not visible from both sides, and no invasive weeds sticker at all. Authorities are searching for the rightful owners to discuss fines.
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