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Danb6177
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5/14/2016 11:57:31 AM
Posted: 6 months ago
Im curious about the way we date things. Not the process Im fine with that but the things that we are dating. When a fossil is found for example what happens next? How is it dated? I assume by the rocks that are around it?
If so, which rocks? Just curious overall about the way this is done.
Rukado
Posts: 527
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5/15/2016 1:08:49 AM
Posted: 6 months ago
Mostly, fossils are dated by the kind of fossil it is and other fossils found near it. For example, if you find a fossil of a Brontosaurus, you can look in a book and declare the fossil to be about 155 million years old.

If you find something like a sturgeon (a common fish), because it's commonly found in low rock and is alive today, you'll look for other fossils to date it. If you find a brontosaurs fossil next to it, you can date it at about 155 million years old. (But, brontosaur fossils are very rare, so you'll end up looking for another fossil to use as an index).
Danb6177
Posts: 433
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5/15/2016 9:16:59 AM
Posted: 6 months ago
At 5/15/2016 1:08:49 AM, Rukado wrote:
Mostly, fossils are dated by the kind of fossil it is and other fossils found near it. For example, if you find a fossil of a Brontosaurus, you can look in a book and declare the fossil to be about 155 million years old.

If you find something like a sturgeon (a common fish), because it's commonly found in low rock and is alive today, you'll look for other fossils to date it. If you find a brontosaurs fossil next to it, you can date it at about 155 million years old. (But, brontosaur fossils are very rare, so you'll end up looking for another fossil to use as an index).

Right but they don't use radiometric dating on bones, they date the rocks correct? What I wanna know is how they choose what rocks to date to determine a fossils age. Or am I wrong in saying that they date the rocks?
Rukado
Posts: 527
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5/15/2016 6:53:19 PM
Posted: 6 months ago
At 5/15/2016 9:16:59 AM, Danb6177 wrote:
Right but they don't use radiometric dating on bones, they date the rocks correct? What I wanna know is how they choose what rocks to date to determine a fossils age. Or am I wrong in saying that they date the rocks?

The vast majority of fossils are dated by the presumed age of the fossil, as explained above. Radiometric dating is not used on fossils (that's not an absolute, but you'll never find an Evolutionist who'll carbon date a dinosaur bone, because he has zero chance of getting the date he wants).

Occasionally, radiometric dating is used nearby rocks, but the results are often thrown out (assumed faulty) if they conflict with the presumed age of the fossil. A favorite radiometric dating method for fossils is to find a lava flow above or below the the fossil and then 40K-40Ar date the lava flow. The assumption is that the heat of the lava drives out the argon that was in the lava, and so when the lava cools, there's a potassium clock set to zero and all the argon in the lava rock today was created by potassium decay from when the lava cooled. There are several flaws with this, first being that we know by observation of new lava rock that not all the original argon was driven out by the heat.

The most revered radiometric dating method is Uranium-lead which is usually used on zircon crystals (much harder to find than lava flows, relative to fossils). U238 has a half-life of 4.47 billion years. It should be noted that the half-life of elements used in radiometric dating has some correlation to the resulting dates from that method. Given the U238 has a half-life of what is believed to be about the age of the earth, it's a great tool to come up with ages fitting the establishment's claimed age of the Earth. Researchers not wanting dates in the millions of years wouldn't use Uranium-lead dating.
Danb6177
Posts: 433
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5/15/2016 8:30:20 PM
Posted: 6 months ago
At 5/15/2016 6:53:19 PM, Rukado wrote:
At 5/15/2016 9:16:59 AM, Danb6177 wrote:
Right but they don't use radiometric dating on bones, they date the rocks correct? What I wanna know is how they choose what rocks to date to determine a fossils age. Or am I wrong in saying that they date the rocks?

The vast majority of fossils are dated by the presumed age of the fossil, as explained above. Radiometric dating is not used on fossils (that's not an absolute, but you'll never find an Evolutionist who'll carbon date a dinosaur bone, because he has zero chance of getting the date he wants).

Ok so what about the first ones. For example the first homo habilis ever found, I believe it was by the Leakeys. So they are exploring and they come to a cave (maybe it was a cave I do not know) and they find some cranium and a few teeth. Ok so these are from a new species never found before so how does the process of dating these happen? what are the leakeys gonna date? They cannot compare the bones so something has to me dated. im sorry for the many questions and im not trying to debate the topic. I just want to understand it better.
Occasionally, radiometric dating is used nearby rocks, but the results are often thrown out (assumed faulty) if they conflict with the presumed age of the fossil. A favorite radiometric dating method for fossils is to find a lava flow above or below the the fossil and then 40K-40Ar date the lava flow. The assumption is that the heat of the lava drives out the argon that was in the lava, and so when the lava cools, there's a potassium clock set to zero and all the argon in the lava rock today was created by potassium decay from when the lava cooled. There are several flaws with this, first being that we know by observation of new lava rock that not all the original argon was driven out by the heat.

The most revered radiometric dating method is Uranium-lead which is usually used on zircon crystals (much harder to find than lava flows, relative to fossils). U238 has a half-life of 4.47 billion years. It should be noted that the half-life of elements used in radiometric dating has some correlation to the resulting dates from that method. Given the U238 has a half-life of what is believed to be about the age of the earth, it's a great tool to come up with ages fitting the establishment's claimed age of the Earth. Researchers not wanting dates in the millions of years wouldn't use Uranium-lead dating.
How do they come up with that half life number?
Rukado
Posts: 527
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5/15/2016 9:08:20 PM
Posted: 6 months ago
At 5/15/2016 8:30:20 PM, Danb6177 wrote:

Ok so what about the first ones. For example the first homo habilis ever found, I believe it was by the Leakeys. So they are exploring and they come to a cave (maybe it was a cave I do not know) and they find some cranium and a few teeth. Ok so these are from a new species never found before so how does the process of dating these happen? what are the leakeys gonna date? They cannot compare the bones so something has to me dated. im sorry for the many questions and im not trying to debate the topic. I just want to understand it better.

I believe h. habilis was found above a lava flow K-Ar dated at 2.1mya. I don't know how a more precise date was obtained.

How do they come up with that half life number?

Half-life is found by watching how fast something decays. This can be hard to do for very long half-lives. Tellurium-128 has a half-life of 8000000000000000 Billion years.
Looncall
Posts: 448
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5/15/2016 10:54:20 PM
Posted: 6 months ago
At 5/15/2016 6:53:19 PM, Rukado wrote:
At 5/15/2016 9:16:59 AM, Danb6177 wrote:
Right but they don't use radiometric dating on bones, they date the rocks correct? What I wanna know is how they choose what rocks to date to determine a fossils age. Or am I wrong in saying that they date the rocks?

The vast majority of fossils are dated by the presumed age of the fossil, as explained above. Radiometric dating is not used on fossils (that's not an absolute, but you'll never find an Evolutionist who'll carbon date a dinosaur bone, because he has zero chance of getting the date he wants).

Occasionally, radiometric dating is used nearby rocks, but the results are often thrown out (assumed faulty) if they conflict with the presumed age of the fossil. A favorite radiometric 'dating method for fossils is to find a lava flow above or below the the fossil and then 40K-40Ar date the lava flow. The assumption is that the heat of the lava drives out the argon that was in the lava, and so when the lava cools, there's a potassium clock set to zero and all the argon in the lava rock today was created by potassium decay from when the lava cooled. There are several flaws with this, first being that we know by observation of new lava rock that not all the original argon was driven out by the heat.

The most revered radiometric dating method is Uranium-lead which is usually used on zircon crystals (much harder to find than lava flows, relative to fossils). U238 has a half-life of 4.47 billion years. It should be noted that the half-life of elements used in radiometric dating has some correlation to the resulting dates from that method. Given the U238 has a half-life of what is believed to be about the age of the earth, it's a great tool to come up with ages fitting the establishment's claimed age of the Earth. Researchers not wanting dates in the millions of years wouldn't use Uranium-lead dating.

This post is disgustingly dishonest.

The half-life constrains the time range that it is possible to date with a certain isotope. If radioactive atoms decay away during the time span of interest, there is nothing to measure. If insufficient decay product is produced, there is again nothing to measure.

I have made my living measuring radioactivity for the last thirty years. I am fed up with the bare-faced lies of creationists.
The metaphysicist has no laboratory.
RuvDraba
Posts: 6,033
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5/15/2016 11:44:40 PM
Posted: 6 months ago
At 5/14/2016 11:57:31 AM, Danb6177 wrote:
Im curious about the way we date things. Not the process Im fine with that but the things that we are dating. When a fossil is found for example what happens next? How is it dated? I assume by the rocks that are around it?
If so, which rocks? Just curious overall about the way this is done.

Dan, I had two goes at responding, but got interrupted... I see that members have answered most of your questions. This isn't my field, but here's an overview that might help tie it together and flesh out some minor detail.

Fossils can be dated by relative means, and absolute means.

Relative Dating
Relative means involve using paleontological indices that correlate with a particular time-period. For example, ammonites are a kind of tentacled snail that appeared in the Devonian period, but died out in the CP extinction. They're easy to identify, and lived for a well-defined period, so if you find a fossil in stratum that also contains ammonites, you know when that creature lived. Moreover, because ammonites can be found worldwide, you know how that creature's timeline relates to that of creatures in other parts of the world.

Absolute Dating
As other members have mentioned, absolute dating normally involves radiometric methods. The basic idea is that certain elements occur as radioactive isotopes. Through nuclear decay, these break down over time to other elements. The mechanisms for breakdown are well known, so if you know how much radiation a given quantity of isotope produces, you know how rapidly it will decay over long periods of time.

A convenient measure for that decay-rate is half-life, which is the time it takes for the amount of radiation from a particular isotope to drop to half the original quantity. Because half-lives of some isotopes can be very long (thousands to millions of years or more), isotopic decay can be very helpful in dating rock and organic substances. Some of the best-known radiometric dating methods include radiocarbon dating [https://en.wikipedia.org...], potassium-argon [https://en.wikipedia.org...]dating, and uranium-lead dating [https://en.wikipedia.org...], though there are others [https://en.wikipedia.org...].

Radioactive decay starts with a 'parent' isotope, and can produce one or more 'daughter' isotopes. When you know the ratio of parent to daughter, you know roughly how long the isotope has been decaying (essentially, the time since it first formed.)

In radiocarbon dating, it's convenient because living organisms accumulate carbon constantly, while dead organisms don't. But radioactive carbon breaks down constantly, so dead organisms have a lot less radioactive carbon in them than living organisms, and you can work out the difference, and hence how long it has been since the organism died. However, radioactive carbon (Carbon-14) has a fairly short half-life of only 5730 years [https://en.wikipedia.org...], and many fossils lose their carbon to other minerals anyway as part of the fossilisation process. So other methods are needed.

With other methods, the ratio of parent to daughter isotopes only tells you when the isotope first formed. That would be great for dating the Earth, but not so useful for dating fossils. However, for some substances, a key physical reaction (e.g. heating) can eject a 'daughter' isotope while keeping the parent. This resets the isotopic 'clock' to zero, and so you can date when that reaction occurred -- which might also be at or close to the time that the creature died, depending on what the minerals are, and where they're found.

As with all scientific measurement, environmental conditions can affect accuracy, and so can sample purity and the precision of your tools. So absolute dating normally needs more than dating method... he more methods you use, the more you eliminate variables affecting the precision of individual methods. And the the more multiple methods agree, the more confident you can be of accuracy. And you can correlate absolute and relative dating methods too, so this can help build both a geological and a biological timeline in parallel. The more independent methods you have, the more samples you use, and the more widespread they are, the more precise the tools, the more accurate and comprehensive the timelines become.

I hope that may help.
user13579
Posts: 822
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5/16/2016 12:17:10 AM
Posted: 6 months ago
At 5/15/2016 9:08:20 PM, Rukado wrote:
At 5/15/2016 8:30:20 PM, Danb6177 wrote:

Ok so what about the first ones. For example the first homo habilis ever found, I believe it was by the Leakeys. So they are exploring and they come to a cave (maybe it was a cave I do not know) and they find some cranium and a few teeth. Ok so these are from a new species never found before so how does the process of dating these happen? what are the leakeys gonna date? They cannot compare the bones so something has to me dated. im sorry for the many questions and im not trying to debate the topic. I just want to understand it better.

I believe h. habilis was found above a lava flow K-Ar dated at 2.1mya. I don't know how a more precise date was obtained.

How do they come up with that half life number?

Half-life is found by watching how fast something decays. This can be hard to do for very long half-lives. Tellurium-128 has a half-life of 8000000000000000 Billion years.

You can watch it for 5 minutes, and count how many atoms decay in that 5 minutes, and compare that to how many atoms didn't decay to figure out the half-life.
Science in a nutshell:
"Facts are neither true nor false. They simply are."
"All scientific knowledge is provisional. Even facts are provisional."
"We can be absolutely certain that we have a moon, we can be absolutely certain that water is made out of H2O, and we can be absolutely certain that the Earth is a sphere!"
"Scientific knowledge is a body of statements of varying degrees of certainty -- some most unsure, some nearly sure, none absolutely certain."
Rukado
Posts: 527
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5/16/2016 12:38:30 AM
Posted: 6 months ago
At 5/15/2016 10:54:20 PM, Looncall wrote:
This post is disgustingly dishonest.

The half-life constrains the time range that it is possible to date with a certain isotope. If radioactive atoms decay away during the time span of interest, there is nothing to measure. If insufficient decay product is produced, there is again nothing to measure.

I have made my living measuring radioactivity for the last thirty years. I am fed up with the bare-faced lies of creationists.

Your post is disgustingly stupid. Specifically, what did I say that you found fault with?
Aran55633
Posts: 109
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5/16/2016 1:05:47 AM
Posted: 6 months ago
The others have all ready explained it well, and as Ruv pointed out, multiple parent isotope-to-daughter isotope measurements are often used to determine the age of a formation, with any nonconforming data being discarded and a mean value being derived from that data which is judged meaningful and accurate.

When these various isotopes provide the same results, that alone is compelling evidence of their reliability, but these dating methods can be verified in other ways.

As an example, here is an interesting piece:

http://www.radiolab.org...

That's a podcast featuring Dr. Neil Shubin of the Univ. of Chicago. Listen to the first ten minutes.

Alternatively, you could read this:

http://freepages.genealogy.rootsweb.ancestry.com...

The first time I read about this a couple years ago, I got chills. I mean, that is just too cool.
RuvDraba
Posts: 6,033
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5/16/2016 2:08:52 AM
Posted: 6 months ago
At 5/16/2016 1:05:47 AM, Aran55633 wrote:
When these various isotopes provide the same results, that alone is compelling evidence of their reliability, but these dating methods can be verified in other ways.

As an example, you could read this:

http://freepages.genealogy.rootsweb.ancestry.com...

The first time I read about this a couple years ago, I got chills. I mean, that is just too cool.

Thank you for linking, Aran. It seems promising, but also appeared in Nature in 1963! [http://www.nature.com...] Do you know whether any subsequent work has been done to refine and qualify coral study as a prospective dating technique?
distraff
Posts: 1,004
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5/16/2016 2:12:54 AM
Posted: 6 months ago
At 5/14/2016 11:57:31 AM, Danb6177 wrote:
Im curious about the way we date things. Not the process Im fine with that but the things that we are dating. When a fossil is found for example what happens next? How is it dated? I assume by the rocks that are around it?
If so, which rocks? Just curious overall about the way this is done.

Don't listen to some of the creationists on this thread. This claim that most carbon dating is thrown out lacks any evidence whatsoever. Scientists can't just make up dates from nothing as this is completely unscientific. Radiometric dating is expensive and would never be done if most of its results get thrown out.

Fossils are dated by the rocks they exist in or are near to. If I find a new fossil in a certain rock layer, that rock layer may have already been dated previously and so that is the date assigned to the fossil. They have to provide a rational based on radiometric dating as to why they dated the fossil a certain way.

For example, lets say that we found a trilobite in the Wheeler Formation. The wheeler formation was dated at about 507 million years old. Therefore the fossil will be estimated to be about 509 million years old. Dating by using the general layer the fossil was found in is called relative dating.

A more accurate form of dating is called absolute dating and this involves dating the exact rock the fossil is found in. This is used with the right rock and if there is funding.

The radiometric dating method used depends on the type and condition of the rock. Certain conditions will make different dating methods inaccurate.

Creationist arguments against radiometric dating are easily refuted.
Google:
radiometric site:talkorigins.org
distraff
Posts: 1,004
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5/16/2016 2:15:06 AM
Posted: 6 months ago
At 5/15/2016 1:08:49 AM, Rukado wrote:
Mostly, fossils are dated by the kind of fossil it is and other fossils found near it. For example, if you find a fossil of a Brontosaurus, you can look in a book and declare the fossil to be about 155 million years old.

If you find something like a sturgeon (a common fish), because it's commonly found in low rock and is alive today, you'll look for other fossils to date it. If you find a brontosaurs fossil next to it, you can date it at about 155 million years old. (But, brontosaur fossils are very rare, so you'll end up looking for another fossil to use as an index).

Fossils are dated according to the rocks they are found in. So if one fossils was dated to be 155 million years old, then another fossil found in the same layer will be about that age as well. However if they are found in different layers you can't assume they are about the same age.
distraff
Posts: 1,004
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5/16/2016 2:45:28 AM
Posted: 6 months ago
At 5/15/2016 6:53:19 PM, Rukado wrote:
At 5/15/2016 9:16:59 AM, Danb6177 wrote:
Right but they don't use radiometric dating on bones, they date the rocks correct? What I wanna know is how they choose what rocks to date to determine a fossils age. Or am I wrong in saying that they date the rocks?

The vast majority of fossils are dated by the presumed age of the fossil, as explained above.

No, they are based on the age of the fossil layer they are found in (relative dating) or in some cases the exact rock they are found in (absolute dating). These dates come from radiometric dating. They are not presumed.

Radiometric dating is not used on fossils (that's not an absolute,

Because dating methods work on rocks not fossils.

but you'll never find an Evolutionist who'll carbon date a dinosaur bone, because he has zero chance of getting the date he wants).

The problem is that carbon degrades so quickly that there is so little of it left from old fossils that the margin of error is larger than the amount of carbon remaining so it is not accurate for very old fossils. There are plenty of other compounds that degrade more slowly and are more accurate.

Occasionally, radiometric dating is used nearby rocks, but the results are often thrown out (assumed faulty) if they conflict with the presumed age of the fossil.

Provide one example where this has happened.

A favorite radiometric dating method for fossils is to find a lava flow above or below the the fossil and then 40K-40Ar date the lava flow. The assumption is that the heat of the lava drives out the argon that was in the lava, and so when the lava cools, there's a potassium clock set to zero and all the argon in the lava rock today was created by potassium decay from when the lava cooled. There are several flaws with this, first being that we know by observation of new lava rock that not all the original argon was driven out by the heat.

Yes there are flaws and there is a margin of error. Occasionally the excess Ar can be trapped in the rock if it crystallizes but this represents only a small minority of cases. If this happens then the age will show up as a few hundred thousand to a few million years older than the actual age. But for very old rock this margin of error that happens for only a few samples is acceptable.

The most revered radiometric dating method is Uranium-lead which is usually used on zircon crystals (much harder to find than lava flows, relative to fossils). U238 has a half-life of 4.47 billion years. It should be noted that the half-life of elements used in radiometric dating has some correlation to the resulting dates from that method. Given the U238 has a half-life of what is believed to be about the age of the earth, it's a great tool to come up with ages fitting the establishment's claimed age of the Earth. Researchers not wanting dates in the millions of years wouldn't use Uranium-lead dating.

Because it has a very large half-life is not not very accurate on young samples and works best on layers very deep in the earth. However there are dating methods that are accurate.

If radiometric dating was innacurate then we wouldn't find many different dating methods converging on the same date for many samples like we do. Also, the dates would be random so deeper strata would not be dated as older than higher strata yet we find that deeper strata have older dates. Also samples would almost always be thrown out if radiometric dating was inaccurate and would cost hundreds of thousands of dollars to run dozens of tests to get the expected date. There is no evidence this sort of thing ever happens.
Rukado
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5/16/2016 3:39:54 AM
Posted: 6 months ago
At 5/16/2016 2:12:54 AM, distraff wrote:

Don't listen to some of the creationists on this thread. This claim that most carbon dating is thrown out lacks any evidence whatsoever. Scientists can't just make up dates from nothing as this is completely unscientific. Radiometric dating is expensive and would never be done if most of its results get thrown out.

Are you dumb, or did your @sshole just overcame you?

I accept that is just an innocent mistake on your part accusing me of saying most carbon dates are thrown out. The only thing I've said about carbon dating is that it's not used on dinosaur bones. But, if you're going to be an @ss, try to be a little more rigorous. In everything you've posted, you've been sloppy with representing what I've said.

Yes, radiometric dating is expensive (in part because they pay for more dates than they accept). That's a convenient reason not to use it more often. I didn't say "most" dates are thrown out (more of your slop). I said "often" dates are thrown out. But, I'm not going to quibble, I believe most dates are thrown out (talk to the labs). It's not so expensive that they abandon radiometric dating. A usable date in a published paper can be a very valuable thing.
distraff
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5/16/2016 3:54:46 AM
Posted: 6 months ago
At 5/16/2016 3:39:54 AM, Rukado wrote:
At 5/16/2016 2:12:54 AM, distraff wrote:

Don't listen to some of the creationists on this thread. This claim that most carbon dating is thrown out lacks any evidence whatsoever. Scientists can't just make up dates from nothing as this is completely unscientific. Radiometric dating is expensive and would never be done if most of its results get thrown out.

I didn't say "most" dates are thrown out (more of your slop). I said "often" dates are thrown out.

The only thing I've said about carbon dating is that it's not used on dinosaur bones.

The thing about carbon dating was a typo on my part. What I meant was radiometric dating. Apologies.

Yes, radiometric dating is expensive (in part because they pay for more dates than they accept). That's a convenient reason not to use it more often.

Unfortunately Congress does not find scientific research funding adequately and scientists are often forced to work according to very strict financial limits. Also if the layer a fossil is in is already well dated then dating again is a waste of funding.

But, I'm not going to quibble, I believe most dates are thrown out (talk to the labs). It's not so expensive that they abandon radiometric dating. A usable date in a published paper can be a very valuable thing.

I guess this depends on whether you used the word "often" to mean "most" or "some." Unfortunately you don't present any evidence showing how often they are thrown out, or any examples of this actually happening. What really matters is how often this is happening and actually getting concrete examples of this happening that shows structural flaws in radiometric dating.
Looncall
Posts: 448
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5/16/2016 1:50:41 PM
Posted: 6 months ago
At 5/16/2016 12:38:30 AM, Rukado wrote:
At 5/15/2016 10:54:20 PM, Looncall wrote:
This post is disgustingly dishonest.

The half-life constrains the time range that it is possible to date with a certain isotope. If radioactive atoms decay away during the time span of interest, there is nothing to measure. If insufficient decay product is produced, there is again nothing to measure.

I have made my living measuring radioactivity for the last thirty years. I am fed up with the bare-faced lies of creationists.

Your post is disgustingly stupid. Specifically, what did I say that you found fault with?

I take great exception to your saying that scientists who use dating techniques fiddle their data to obtain pre-decided results.

That sort of thing may be common in religious apologetics, but it makes no sense when scientists are trying to find out actual dates in order to solve various problems.
The metaphysicist has no laboratory.
RuvDraba
Posts: 6,033
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5/16/2016 6:28:20 PM
Posted: 6 months ago
At 5/16/2016 1:50:41 PM, Looncall wrote:
At 5/16/2016 12:38:30 AM, Rukado wrote:
At 5/15/2016 10:54:20 PM, Looncall wrote:
This post is disgustingly dishonest.

The half-life constrains the time range that it is possible to date with a certain isotope. If radioactive atoms decay away during the time span of interest, there is nothing to measure. If insufficient decay product is produced, there is again nothing to measure.

I have made my living measuring radioactivity for the last thirty years. I am fed up with the bare-faced lies of creationists.

Specifically, what did I say that you found fault with?

I take great exception to your saying that scientists who use dating techniques fiddle their data to obtain pre-decided results.

That sort of thing may be common in religious apologetics, but it makes no sense when scientists are trying to find out actual dates in order to solve various problems.

I agree, Loon. The role of metrics in science is critical, and if scientists who work on measuring things started fudging numbers to look impressively accurate, the scientists depending on measurements for modelling would sniff it out through the error bars, detect it through correlation, and want to lynch them. :)

The problem is, people who've only ever known the evasions and deceits of religious apologetics don't actually get just how much honesty and diligence are created from transparency and accountability because religious apologetics uphold neither. So they imagine that scientists do what they already know theologians do. :p

Science has all manner of challenges with respect to accuracy and accountability -- especially on increasingly large, poorly curated and sometimes unshared data sets. But a system that depends so much on systematic correlation for knowledge is not prone to letting deliberate fudging escape without censure. :)
Danb6177
Posts: 433
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5/16/2016 6:39:23 PM
Posted: 6 months ago
Sorry for delay, ill get back to this tomorrow. Jury duty today. I have read responses and have replies ready. Thanx
Rukado
Posts: 527
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5/16/2016 7:09:20 PM
Posted: 6 months ago
At 5/16/2016 2:45:28 AM, distraff wrote:
At 5/15/2016 6:53:19 PM, Rukado wrote:
The vast majority of fossils are dated by the presumed age of the fossil, as explained above.

No, they are based on the age of the fossil layer they are found in (relative dating) or in some cases the exact rock they are found in (absolute dating). These dates come from radiometric dating. They are not presumed.

Distraff, you're stupid. Stop trying to "educate" me or whatever the H3ll you think you're doing. You tell me I'm wrong, and then you explain exactly what I've already said (except you used anal language). I also used the word "presumed" to reflect my lack of blind allegiance to dating fossils by an age a book says they are (which is the most common method "scientists" use to date fossils).

The problem is that carbon degrades so quickly that there is so little of it left from old fossils that the margin of error is larger than the amount of carbon remaining so it is not accurate for very old fossils. There are plenty of other compounds that degrade more slowly and are more accurate.

Look at you whining about the lack of accuracy of some radiometric dating.

Provide one example where this has happened.

Yes there are flaws and there is a margin of error. Occasionally the excess Ar can be trapped in the rock if it crystallizes but this represents only a small minority of cases.

But, you wouldn't throw out bad dates obtained from rock with trapped argon.... because you, idiot, just challenged me to provide one example of where dates are thrown out.

If radiometric dating was innacurate then we wouldn't find many different dating methods converging on the same date for many samples like we do.

Because different dating methods are calibrated against each other. Because non-conforming dates are discarded (presumed contamination). Etc. Use your brain.
bonsai
Posts: 172
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5/16/2016 9:07:24 PM
Posted: 6 months ago
At 5/14/2016 11:57:31 AM, Danb6177 wrote:
Im curious about the way we date things. Not the process Im fine with that but the things that we are dating. When a fossil is found for example what happens next? How is it dated? I assume by the rocks that are around it?
If so, which rocks? Just curious overall about the way this is done. : :

It's impossible for scientists to know for sure if their dating methods work because they never had anyone come back from the past to tell them if they're accurate. Dating methods are all based on theories.
Looncall
Posts: 448
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5/16/2016 10:45:08 PM
Posted: 6 months ago
At 5/16/2016 9:07:24 PM, bonsai wrote:
At 5/14/2016 11:57:31 AM, Danb6177 wrote:
Im curious about the way we date things. Not the process Im fine with that but the things that we are dating. When a fossil is found for example what happens next? How is it dated? I assume by the rocks that are around it?
If so, which rocks? Just curious overall about the way this is done. : :

It's impossible for scientists to know for sure if their dating methods work because they never had anyone come back from the past to tell them if they're accurate. Dating methods are all based on theories.

Balderdash. A scientific theory is a throughly-substantiated explanation of some aspect of reality. It's not a wild guess, as creationist liars would have you think.

Many phenomena, such as radioactivity, are very well understood. Diverse phenomena can be used for dating and be cross-checked. That cross-checking .... checks out.

Events from the distant past, such as fossil nuclear reactors, are available as further cross checks.
The metaphysicist has no laboratory.
Aran55633
Posts: 109
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5/16/2016 11:03:38 PM
Posted: 6 months ago
At 5/16/2016 2:08:52 AM, RuvDraba wrote:
At 5/16/2016 1:05:47 AM, Aran55633 wrote:
When these various isotopes provide the same results, that alone is compelling evidence of their reliability, but these dating methods can be verified in other ways.

As an example, you could read this:

http://freepages.genealogy.rootsweb.ancestry.com...

The first time I read about this a couple years ago, I got chills. I mean, that is just too cool.

Thank you for linking, Aran. It seems promising, but also appeared in Nature in 1963! [http://www.nature.com...] Do you know whether any subsequent work has been done to refine and qualify coral study as a prospective dating technique?

http://www.ptep-online.com...

This seems to be exactly what you're asking about, haha. But yeah, there's actually quite a bit of material out there exploring this topic.

I think it's simply brilliant.
distraff
Posts: 1,004
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5/17/2016 12:51:48 AM
Posted: 6 months ago
At 5/16/2016 7:09:20 PM, Rukado wrote:
At 5/16/2016 2:45:28 AM, distraff wrote:
At 5/15/2016 6:53:19 PM, Rukado wrote:
The vast majority of fossils are dated by the presumed age of the fossil, as explained above.

No, they are based on the age of the fossil layer they are found in (relative dating) or in some cases the exact rock they are found in (absolute dating). These dates come from radiometric dating. They are not presumed.

Distraff, you're stupid. Stop trying to "educate" me or whatever the H3ll you think you're doing.

Wow, very mature, trolling people in the science forum. How old are you? 14? I can tell you hate education but don't use that as an excuse to skip pre-algebra class.

You tell me I'm wrong, and then you explain exactly what I've already said (except you used anal language).

I am sure you love it when guys use anal language on you.

I also used the word "presumed" to reflect my lack of blind allegiance to dating fossils by an age a book says they are (which is the most common method "scientists" use to date fossils).

No, scientists do not use books to date fossils. They look at the rock or the strata layer the fossil is in. Give me one example where scientists did this. Where are you getting this nonsense? It is certainly not coming from your high school.

The problem is that carbon degrades so quickly that there is so little of it left from old fossils that the margin of error is larger than the amount of carbon remaining so it is not accurate for very old fossils. There are plenty of other compounds that degrade more slowly and are more accurate.

Look at you whining about the lack of accuracy of some radiometric dating.

No, different methods work on different fossils and experts pick the methods that will be the most accurate. When used properly the margin of error of fossil dating is 2-5%.

Provide one example where this has happened.

Yes there are flaws and there is a margin of error. Occasionally the excess Ar can be trapped in the rock if it crystallizes but this represents only a small minority of cases.

But, you wouldn't throw out bad dates obtained from rock with trapped argon.... because you, idiot, just challenged me to provide one example of where dates are thrown out.

You think that you are the only one who knows about this? Experts in fossil dating learned about these limitations in college in much greater detail than will ever know so they know to avoid using dating methods on fossils in conditions that will make those methods inaccurate. Also these inaccuracies only throw off the date by a few hundred thousand to a few million years. This is nothing if we are dating in 500 million year old strata. You creationists talk about these limitations as if scientists are blind to them. Understanding and dealing with these limitations is literally the scientists' job.

If radiometric dating was innacurate then we wouldn't find many different dating methods converging on the same date for many samples like we do.

Because different dating methods are calibrated against each other. Because non-conforming dates are discarded (presumed contamination). Etc. Use your brain.

Give me one example of a date being discarded only because it didn't conform? How do you know that this even happens very often? Where are you getting this garbage?
distraff
Posts: 1,004
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5/17/2016 1:01:27 AM
Posted: 6 months ago
At 5/16/2016 9:07:24 PM, bonsai wrote:
At 5/14/2016 11:57:31 AM, Danb6177 wrote:
Im curious about the way we date things. Not the process Im fine with that but the things that we are dating. When a fossil is found for example what happens next? How is it dated? I assume by the rocks that are around it?
If so, which rocks? Just curious overall about the way this is done. : :

It's impossible for scientists to know for sure if their dating methods work because they never had anyone come back from the past to tell them if they're accurate. Dating methods are all based on theories.

Actually the know very well that the methods work because different dating methods are based on very different physical properties and numerous methods converge on similar dates for the same fossils and strata. Dating methods not only agree but also tend to have older dates the lower in the strata you go. It is also consistent with luminescence dating, Milankovitch cycles.

Below is a link to data from a study that compared dates from multiple dating methods showing that they agree:
http://www.talkorigins.org...
bonsai
Posts: 172
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5/17/2016 3:41:40 AM
Posted: 6 months ago
At 5/16/2016 10:45:08 PM, Looncall wrote:
At 5/16/2016 9:07:24 PM, bonsai wrote:
At 5/14/2016 11:57:31 AM, Danb6177 wrote:
Im curious about the way we date things. Not the process Im fine with that but the things that we are dating. When a fossil is found for example what happens next? How is it dated? I assume by the rocks that are around it?
If so, which rocks? Just curious overall about the way this is done. : :

It's impossible for scientists to know for sure if their dating methods work because they never had anyone come back from the past to tell them if they're accurate. Dating methods are all based on theories.

Balderdash. A scientific theory is a throughly-substantiated explanation of some aspect of reality. It's not a wild guess, as creationist liars would have you think.

Many phenomena, such as radioactivity, are very well understood. Diverse phenomena can be used for dating and be cross-checked. That cross-checking .... checks out.

Events from the distant past, such as fossil nuclear reactors, are available as further cross checks. : :

A theory is not the truth. It's based on subjective evidence that can't possibly be supported by anything else than a guess.
bonsai
Posts: 172
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5/17/2016 3:52:39 AM
Posted: 6 months ago
At 5/17/2016 1:01:27 AM, distraff wrote:
At 5/16/2016 9:07:24 PM, bonsai wrote:
At 5/14/2016 11:57:31 AM, Danb6177 wrote:
Im curious about the way we date things. Not the process Im fine with that but the things that we are dating. When a fossil is found for example what happens next? How is it dated? I assume by the rocks that are around it?
If so, which rocks? Just curious overall about the way this is done. : :

It's impossible for scientists to know for sure if their dating methods work because they never had anyone come back from the past to tell them if they're accurate. Dating methods are all based on theories.

Actually the know very well that the methods work because different dating methods are based on very different physical properties and numerous methods converge on similar dates for the same fossils and strata. Dating methods not only agree but also tend to have older dates the lower in the strata you go. It is also consistent with luminescence dating, Milankovitch cycles.

Below is a link to data from a study that compared dates from multiple dating methods showing that they agree:
http://www.talkorigins.org... : :

Scientists don't have any idea how old God's creation is or how he created everything. All their conclusions are theories based on subjective evidence that can't be proven to be true.
distraff
Posts: 1,004
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5/17/2016 4:28:07 AM
Posted: 6 months ago
At 5/17/2016 3:52:39 AM, bonsai wrote:
At 5/17/2016 1:01:27 AM, distraff wrote:
At 5/16/2016 9:07:24 PM, bonsai wrote:
At 5/14/2016 11:57:31 AM, Danb6177 wrote:
Im curious about the way we date things. Not the process Im fine with that but the things that we are dating. When a fossil is found for example what happens next? How is it dated? I assume by the rocks that are around it?
If so, which rocks? Just curious overall about the way this is done. : :

It's impossible for scientists to know for sure if their dating methods work because they never had anyone come back from the past to tell them if they're accurate. Dating methods are all based on theories.

Actually the know very well that the methods work because different dating methods are based on very different physical properties and numerous methods converge on similar dates for the same fossils and strata. Dating methods not only agree but also tend to have older dates the lower in the strata you go. It is also consistent with luminescence dating, Milankovitch cycles.

Below is a link to data from a study that compared dates from multiple dating methods showing that they agree:
http://www.talkorigins.org... : :

Scientists don't have any idea how old God's creation is or how he created everything. All their conclusions are theories based on subjective evidence that can't be proven to be true.

No, there is strong evidence for radiometric dating. It is based on the rate at which certain compounds decay. Here is the formula below:

Final Amount = Initial Amount * e^(time * degrade rate). Different compounds degrade in different ways and the fact that different dating methods independently converge on the same results and are based on the facts we have learned about chemistry is convincing evidence for these dating methods.

Here is a Khan Academy video explaining the K Ar dating method:
https://www.khanacademy.org...