Oldest Weapons in North America Found

[snagged in outlet 3]

http://www.msn.com/en-us/video/wonder/oldest-weapons-in-north-america-discovered-in-texas/vi-BBOTGmN

[Basfis]

Pretty cool. 

I wish they would say how they know what they believe for time.

i can’t wrap my head around dating a rock much less dating the fracturing of a rock for weapon use. 

Still really old really cool. 

[BilletHead]

      Thanks Snagged,

    Like this kind of stuff. There are two shows on PBS I found worth watching. Neanderthal I think it is a one and done but am sure it will repeat. The other is native America. A series. Good stuff to watch,

   BilletHead

[BilletHead]

5 minutes ago, Basfis said:

Pretty cool. 

I wish they would say how they know what they believe for time.

i can’t wrap my head around dating a rock much less dating the fracturing of a rock for weapon use. 

Still really old really cool. 

           https://en.wikipedia.org/wiki/Radiocarbon_dating

BilletHead

[snagged in outlet 3]

 A guy on the TV show Alaskan Frontier knocked out a nice one pretty quick last night.  I couldn't believe how fast he did it.  Pretty cool!

[Basfis]

34 minutes ago, BilletHead said:

           https://en.wikipedia.org/wiki/Radiocarbon_dating

BilletHead

Thanks. So, do we assume there was an organic artifact (like an animal bone) with the spear point to derive the time from? The rock existed before it was shaped. 

[tjm]

37 minutes ago, Basfis said:

i can’t wrap my head around dating a rock much less dating the fracturing of a rock for weapon use. 

They look at all the stuff found next to the rock, in the same layer of sediment-plant or animal matter and just say that if the seeds date xxyears ago then all the things in that layer of mud are that age.

[BilletHead]

35 minutes ago, tjm said:

They look at all the stuff found next to the rock, in the same layer of sediment-plant or animal matter and just say that if the seeds date xxyears ago then all the things in that layer of mud are that age.

yep

[bfishn]

2 hours ago, BilletHead said:

           https://en.wikipedia.org/wiki/Radiocarbon_dating

BilletHead

Not so in this case, and from reading several sources, that may be a cause for controversy;

"The radiocarbon dating method was not used to date the archaeological components at the Friedkin site because there were no carbon samples that would yield reliable and accurate ages. In situ charcoal is not preserved, and all bones are leached of collagen. Dating of bulk sediment organics was not undertaken because these ages are usually inaccurate. For example, two bulk sediment ages from the Clovis horizon (unit 3a) at Excavation Area 8 of the Gault site, located ~400 m upstream of the Friedkin site, produced ages of 7130 ± 40 radiocarbon years before the present (¹⁴C yr B.P.) (CAMS-65535; ~7.9 to ~8.0 ka ago) and 9300 ± 40 ¹⁴C yr B.P. (CAMS-65986; ~10.4 to 10.6 ka ago) (12). These ages are 2 to 5 ka younger than the known age of Clovis."

"Instead, the OSL dating method was used to determine the age of the artifacts at the Friedkin site by dating the floodplain sediments that bury them. This method is well suited for the site because according to the geological principle of inclusions, any items, such as artifacts, in an undisturbed sedimentary deposit, such as the floodplain clays at the Friedkin site, are at least as old as the sediments that contain them. The OSL method has been used for decades to date Late Quaternary deposits and has been shown to yield accurate ages; many tests have shown that OSL ages are in agreement with radiocarbon ages (13). Luminescence dating has also been used to successfully date archaeological sites in North America such as the Clovis horizon at Pavo Real, Texas, and the Archaic, Paleoindian, and pre-Clovis horizons at the Gault site, Texas (12, 14, 15)."

[BilletHead]

                  

18 minutes ago, bfishn said:

Not so in this case, and from reading several sources, that may be a cause for controversy;

"The radiocarbon dating method was not used to date the archaeological components at the Friedkin site because there were no carbon samples that would yield reliable and accurate ages. In situ charcoal is not preserved, and all bones are leached of collagen. Dating of bulk sediment organics was not undertaken because these ages are usually inaccurate. For example, two bulk sediment ages from the Clovis horizon (unit 3a) at Excavation Area 8 of the Gault site, located ~400 m upstream of the Friedkin site, produced ages of 7130 ± 40 radiocarbon years before the present (¹⁴C yr B.P.) (CAMS-65535; ~7.9 to ~8.0 ka ago) and 9300 ± 40 ¹⁴C yr B.P. (CAMS-65986; ~10.4 to 10.6 ka ago) (12). These ages are 2 to 5 ka younger than the known age of Clovis."

"Instead, the OSL dating method was used to determine the age of the artifacts at the Friedkin site by dating the floodplain sediments that bury them. This method is well suited for the site because according to the geological principle of inclusions, any items, such as artifacts, in an undisturbed sedimentary deposit, such as the floodplain clays at the Friedkin site, are at least as old as the sediments that contain them. The OSL method has been used for decades to date Late Quaternary deposits and has been shown to yield accurate ages; many tests have shown that OSL ages are in agreement with radiocarbon ages (13). Luminescence dating has also been used to successfully date archaeological sites in North America such as the Clovis horizon at Pavo Real, Texas, and the Archaic, Paleoindian, and pre-Clovis horizons at the Gault site, Texas (12, 14, 15)."

 Thanks for the clarification on that particular site. 

BilletHead