I’m admittedly not too familiar with it. I imagine it’s a bit like thermoluminescence-- burning off some of the material and measuring how much crap is released or some such.
Please expand my knowledge.
[quote]pushharder wrote:
[quote]SteelyD wrote:
[quote]pushharder wrote:
“One problem: The ancient dates came from the soil, not the artifacts themselves.”[/quote]
Is that your words or did I miss that in the article?[/quote]
I put it in quotes. It’s in the article.[/quote]
I see now-- sorry, I’m posting from a phone-- I honestly didn’t see the 2nd and 3rd page of the article. I got the whole story now.
[quote]pushharder wrote:
[quote]SteelyD wrote:
I think this is a great story of a researcher staying the course of his hypothesis in the face of adversity from his peers who have a stake in the ‘scientific status quo’
[i]When Stanford proposed this “Solutrean hypothesis” in 1999, colleagues roundly rejected it. One prominent archaeologist suggested that Stanford was throwing his career away.
But now, 13 years later, Stanford and Bruce Bradley, an archaeologist at England’s University of Exeter, lay out a detailed case – bolstered by the curious blade and other stone tools recently found in the mid-Atlantic – in a new book, “Across Atlantic Ice.”[/i]
Sounds like a great book to pick up.[/quote]
“Lowery dated the soil layer holding the anvil and other stone tools with two methods, radiocarbon dating and a newer technique, optical stimulated luminescence. Both returned an age of at least 21,000 years.”
Wanna discuss?[/quote]
So, what’s on your mind?
[quote]SteelyD wrote:
I’m admittedly not too familiar with it. I imagine it’s a bit like thermoluminescence-- burning off some of the material and measuring how much crap is released or some such.
Please expand my knowledge.[/quote]
It is sort of like that. On a basic level, when a material that is not exposed directly to light is irradiated, these neat little things called “electron traps” are formed. These are pretty complicated, but they are pretty much what they sound like: they capture and store electrons under certain circumstances. when exposed to light (specifically blue-green or infrared excitation depending on circumstances), the electron energy is released causing luminescence. This luminescence is what is measured and used to determine age. Just a few seconds of exposure to sunlight will reset the clock, which is why there are more than a few scientists (myself included) who do not use this method very often. I don’t use it at all. It is supposed to be accurate up to 100,000 years. Great article by the way, Steely. I enjoyed it.
[quote]Dr.Matt581 wrote:
[quote]SteelyD wrote:
I’m admittedly not too familiar with it. I imagine it’s a bit like thermoluminescence-- burning off some of the material and measuring how much crap is released or some such.
Please expand my knowledge.[/quote]
It is sort of like that. On a basic level, when a material that is not exposed directly to light is irradiated, these neat little things called “electron traps” are formed. These are pretty complicated, but they are pretty much what they sound like: they capture and store electrons under certain circumstances. when exposed to light (specifically blue-green or infrared excitation depending on circumstances), the electron energy is released causing luminescence. This luminescence is what is measured and used to determine age. Just a few seconds of exposure to sunlight will reset the clock, which is why there are more than a few scientists (myself included) who do not use this method very often. I don’t use it at all. It is supposed to be accurate up to 100,000 years. Great article by the way, Steely. I enjoyed it.[/quote]
I’m only vaguely familiar with TL from grad school and soils work in New Mexico. I know it’s used on artifacts and such. I remember a couple ‘peer presentations’ from folks looking for ages of surfaces and such but the details are not clear to me. I bet there’s a paragraph in one of my textbooks about it that I probably read at 3am trying to keep my eyes open for the morning exam. 
[quote]SteelyD wrote:
[quote]Dr.Matt581 wrote:
[quote]SteelyD wrote:
I’m admittedly not too familiar with it. I imagine it’s a bit like thermoluminescence-- burning off some of the material and measuring how much crap is released or some such.
Please expand my knowledge.[/quote]
It is sort of like that. On a basic level, when a material that is not exposed directly to light is irradiated, these neat little things called “electron traps” are formed. These are pretty complicated, but they are pretty much what they sound like: they capture and store electrons under certain circumstances. when exposed to light (specifically blue-green or infrared excitation depending on circumstances), the electron energy is released causing luminescence. This luminescence is what is measured and used to determine age. Just a few seconds of exposure to sunlight will reset the clock, which is why there are more than a few scientists (myself included) who do not use this method very often. I don’t use it at all. It is supposed to be accurate up to 100,000 years. Great article by the way, Steely. I enjoyed it.[/quote]
I’m only vaguely familiar with TL from grad school and soils work in New Mexico. I know it’s used on artifacts and such. I remember a couple ‘peer presentations’ from folks looking for ages of surfaces and such but the details are not clear to me. I bet there’s a paragraph in one of my textbooks about it that I probably read at 3am trying to keep my eyes open for the morning exam. ;)[/quote]
I don’t know of anyone that actually enjoys studying TL, except for giant nuclear physics geeks like myself. I wouldn’t even know about optical stimulated luminescence at all except that it was mentioned in my solid-state physics class in grad school and I looked it up. It is a bit of a fad among European scientists right now despite the fact that in almost every situation where it can be used, TL dating can also be used. To be honest, there are too many special conditions and assumptions that have to be made to make it as reliable a form of dating as other methods.
[quote]Dr.Matt581 wrote:
I don’t use it at all. It is supposed to be accurate up to 100,000 years. [/quote]
It seems like this limitation actually makes it a great tool for this type of application. I think the real confidence levels come into play when several methods used in conjunction render similar results (if they’re all in the error bars).
“Law of Superposition” is tricky with archeological digs because of the human element - eg. being able to bury something across soil layers. I think he was alluding to that in the article that you need something to hang your hat on.
[quote]Dr.Matt581 wrote:
I don’t know of anyone that actually enjoys studying TL, except for giant nuclear physics geeks like myself. [/quote]
HA! Yeah, I’m a field guy. I spent most of my education camping on beaches, ledges, forests, or in the desert A lot of digging and breaking shit with 4lb sledge hammers.
[quote]SteelyD wrote:
[quote]Dr.Matt581 wrote:
I don’t use it at all. It is supposed to be accurate up to 100,000 years. [/quote]
It seems like this limitation actually makes it a great tool for this type of application. I think the real confidence levels come into play when several methods used in conjunction render similar results (if they’re all in the error bars).[/quote]
Exactly! I know that in my lab, protocol dictates using as many different dating methods as possible to minimize errors. If the different methods agree, to within the error margins, and our methods are reviewed and verified, we can be very confident it is correct. If the methods do not agree after multiple tests and verification trials, we cannot and do not give a definitive date.
Yeah, I think he was too, which just shows the man’s integrity. He could have easily left that out and it is unlikely anyone would have noticed. This is also why thermal and optical dating is not usually a primary dating method. Even a few seconds of exposure to light or a certain level of heat will reset the clocks to zero.
[quote]anonym wrote:
evolution doesn’t fit in with thermodynamics.[/quote]
Well of course it doesn’t, dummy. The earth is a closed system and the sun doesn’t exist!
[quote]pushharder wrote:
[quote]SteelyD wrote:
[quote]pushharder wrote:
[quote]SteelyD wrote:
I think this is a great story of a researcher staying the course of his hypothesis in the face of adversity from his peers who have a stake in the ‘scientific status quo’
[i]When Stanford proposed this “Solutrean hypothesis” in 1999, colleagues roundly rejected it. One prominent archaeologist suggested that Stanford was throwing his career away.
But now, 13 years later, Stanford and Bruce Bradley, an archaeologist at England’s University of Exeter, lay out a detailed case – bolstered by the curious blade and other stone tools recently found in the mid-Atlantic – in a new book, “Across Atlantic Ice.”[/i]
Sounds like a great book to pick up.[/quote]
“Lowery dated the soil layer holding the anvil and other stone tools with two methods, radiocarbon dating and a newer technique, optical stimulated luminescence. Both returned an age of at least 21,000 years.”
Wanna discuss?[/quote]
So, what’s on your mind?[/quote]
I just find it interesting that’s it’s generally accepted that after around the 10,000 year mark or so Carbon-14 dating becomes unreliable.
Comments, Matt?[/quote]
It doesn’t become unreliable until so much of the C-14 has decayed to make it hard for modern equipment to measure how much is left, which happens after around 60-80,000 years. Not sure where you got the generally accepted thing from. You may be referring to margins of error involved in dating samples. Common margins of error for C-14 samples at less than 10,000 years are +/- 30-50 years. Common margins of error for samples in the 60-80,000 year range tend to be in the +/- 500-1200 year. This is certainly higher, but still acceptable. Beyond that, margins of error go up drastically which is why we use more long-lived radionuclides.
[quote]Cortes wrote:
[quote]pat wrote:
[quote]Grimlorn wrote:
This thread is so disappointing. Pushharder was able to basically twist this into a Atheists vs. Theists thread, when a few posters just made a few smartass comments about creationists who believe the world is 6000 years old. Not all theists. Really wasn’t worth arguing over for 25 pages.[/quote]
Actually I the article Jewbacca posted was well worth the trouble and I have enjoyed the professors comments. [/quote]
X2[/quote]
x9000. Those two things have been worth the significant price of admission and reading a trainwreck. Many many thanks!
[quote]pushharder wrote:
[quote]SteelyD wrote:
[quote]pushharder wrote:
“One problem: The ancient dates came from the soil, not the artifacts themselves.”[/quote]
Is that your words or did I miss that in the article?[/quote]
I put it in quotes. It’s in the article.[/quote]
That wasn’t about the blade found with the tusk. They tested the tusk age and surmised the blade was from the same period.
This thread is STILL going strong?
Time to throw a monkey wrench into the works.
NSFW!
http://blackgifs.com/gifs/nsfw57.gif
lol
[quote]Iron Dwarf wrote:
This thread is STILL going strong?
Time to throw a monkey wrench into the works.
NSFW!
http://blackgifs.com/gifs/nsfw57.gif
lol
[/quote]
My carbon dating methods put her at approximately 18 years of age.
[quote]imhungry wrote:
[quote]Iron Dwarf wrote:
This thread is STILL going strong?
Time to throw a monkey wrench into the works.
NSFW!
http://blackgifs.com/gifs/nsfw57.gif
lol
[/quote]
My carbon dating methods put her at approximately 18 years of age.
[/quote]
Check out this one. Tell me you don’t believe in God after that!
[quote]Aragorn wrote:
[quote]Cortes wrote:
[quote]pat wrote:
[quote]Grimlorn wrote:
This thread is so disappointing. Pushharder was able to basically twist this into a Atheists vs. Theists thread, when a few posters just made a few smartass comments about creationists who believe the world is 6000 years old. Not all theists. Really wasn’t worth arguing over for 25 pages.[/quote]
Actually I the article Jewbacca posted was well worth the trouble and I have enjoyed the professors comments. [/quote]
X2[/quote]
x9000. Those two things have been worth the significant price of admission and reading a trainwreck. Many many thanks![/quote]
It’s certainly an interesting article, but sometimes the numbers just match up neatly by chance and sometimes sophistry can disguise reality.
The premise that the age of the universe is six God-days, plus the ~6000 years of the Bible/Torah is fine, but as soon as you convert God-days into human-years the age comes out to be ~15,000,000,000 years. The age is the same whatever units you use. It doesn’t, however, change the Biblical claim that humans appeared ~6000 years ago.
Also if a day as written doesn’t actually mean a human day of 24 hours, why use the word at all? Why presume to quantify how long the creation process took when none of the authors were there? Even if they had direct word of God knowledge, why would God have played around with the meaning of day, when he would know (being omniscient) what problems it would cause down the line? Either they were being wilfully ambiguous - in the hope that clever people thousands of years hence would decode the ambiguity - or they meant “a day” to be a day.
The pulses of light travelling through an expanding universe concept also works in terms of the numbers, but it’s a thought experiment. Why would God be constrained by the speed of light and therefore take millions of years to create anything in his own expanding universe? What has space expansion at the universal level got to do with how long it takes to seed the Earth with plants or animals? Clever idea, clever maths, but not really related to the basic problem. Certainly nothing to say about a fossil forest deep under layers of rock and coal.