C14

[RenHoek]

I am no scientist. Please explain from an evolutionary standpoint. Lay terms would be helpful.

From: http://www.drdino.com/articles.php?spec=73

Does carbon dating prove the Earth is millions of years old?
Author: Dr. Kent Hovind
Whenever the worldview of evolution is questioned, this topic always comes up. Let me first explain how carbon dating works and then show you the assumptions it is based on. Radiation from the sun strikes the atmosphere of the earth all day long. This energy converts about 21 pounds of nitrogen into radioactive carbon 14. This radioactive carbon 14 slowly decays back into normal, stable nitrogen. Extensive laboratory testing has shown that about half of the C-14 molecules will decay in 5730 years. This is called the half-life. After another 5730 years half of the remaining C-14 will decay leaving only ¼ of the original C-14. It goes from ½ to ¼ to 1/8, etc. In theory it would never totally disappear, but after about 5 half lives the difference is not measurable with any degree of accuracy. This is why most people say carbon dating is only good for objects less than 40,000 years old. Nothing on earth carbon dates in the millions of years, because the scope of carbon dating only extends a few thousand years. Willard Libby invented the carbon dating technique in the early 1950's. The amount of carbon 14 in the atmosphere today (about .0000765%), is assumed there would be the same amount found in living plants or animals since the plants breath CO2 and animals eat plants. Carbon 14 is the radio-active version of carbon.
Since sunlight causes the formation of C-14 in the atmosphere, and normal radioactive decay takes it out, there must be a point where the formation rate and the decay rate equalizes. This is called the point of equilibrium. Let me illustrate: If you were trying to fill a barrel with water but there were holes drilled up the side of the barrel, as you filled the barrel it would begin leaking out the holes. At some point you would be putting it in and it would be leaking out at the same rate. You will not be able to fill the barrel past this point of equilibrium. In the same way the C-14 is being formed and decaying simultaneously. A freshly created earth would require about 30,000 years for the amount of C-14 in the atmosphere to reach this point of equilibrium because it would leak out as it is being filled. Tests indicate that the earth has still not reached equilibrium. There is more C-14 in the atmosphere now than there was 40 years ago. This would prove the earth is not yet 30,000 years old! This also means that plants and animals that lived in the past had less C-14 in them than do plants and animals today. Just this one fact totally upsets data obtained by C-14 dating.

The carbon in the atmosphere normally combines with oxygen to make carbon dioxide (CO2). Plants breathe CO2 and make it part of their tissue. Animals eat the plants and make it part of their tissues. A very small percentage of the carbon plants take in is radioactive C-14. When a plant or animal dies it stops taking in air and food so it should not be able to get any new C-14. The C-14 in the plant or animal will begin to decay back to normal nitrogen. The older an object is, the less carbon-14 it contains. One gram of carbon from living plant material causes a Geiger counter to click 16 times per minute as the C-14 decays. A sample that causes 8 clicks per minute would be 5,730 years old (the sample has gone through one half life), and so on. (See chart on page 46 about C-14). Although this technique looks good at first, carbon-14 dating rests on two simple assumptions. They are, obviously, assuming the amount of carbon-14 in the atmosphere has always been constant, and its rate of decay has always been constant. Neither of these assumptions is provable or reasonable. An illustration may help: Imagine you found a candle burning in a room, and you wanted to determine how long it was burning before you found it. You could measure the present height of the candle (say, seven inches) and the rate of burn (say, an inch per hour). In order to find the length of time since the candle was lit we would be forced to make some assumptions. We would, obviously, have to assume that the candle has always burned at the same rate, and assumes an initial height of the candle.
The answer changes based on the assumptions. Similarly, scientists do not know that the carbon-14 decay rate has been constant. They do not know that the amount of carbon-14 in the atmosphere is constant. Present testing shows the amount of C-14 in the atmosphere has been increasing since it was first measured in the 1950's. This may be tied in to the declining strength of the magnetic field.

 

[billwald]

> Similarly, scientists do not know that the carbon-14 decay rate has been constant.

Young Earth Creationists may, according to their theology, only "know" what the Bible "tells" them.

 

[gluadys]

I am no scientist. Please explain from an evolutionary standpoint. Lay terms would be helpful.

Does carbon dating prove the Earth is millions of years old?
Author: Dr. Kent Hovind

No. Given the short half-life of c14, a measurable trace of it only remains for a few 10 thousands of years. Currently about the maximum date measurable for C14 is about 50,000 years.

For dates of billions of years, one needs to use a different radio-active element such as uranium or radioactive isotopes of potassium, argon, rubidium, etc. which have half-lives in the range of several 100s of millions of years.

Let me first explain how carbon dating works and then show you the assumptions it is based on. Radiation from the sun strikes the atmosphere of the earth all day long. This energy converts about 21 pounds of nitrogen into radioactive carbon 14. This radioactive carbon 14 slowly decays back into normal, stable nitrogen. Extensive laboratory testing has shown that about half of the C-14 molecules will decay in 5730 years. This is called the half-life. After another 5730 years half of the remaining C-14 will decay leaving only ¼ of the original C-14. It goes from ½ to ¼ to 1/8, etc. In theory it would never totally disappear, but after about 5 half lives the difference is not measurable with any degree of accuracy.

This is essentially correct. Except for the origin of the element, the same applies to other radio-active elements, but over a longer time-frame due to the longer half-lives.

The amount of carbon 14 in the atmosphere today (about .0000765%), is assumed there would be the same amount found in living plants or animals since the plants breath CO2 and animals eat plants. Carbon 14 is the radio-active version of carbon.

This is not correct. It is known that the amount and proportion of C14 varies over time. C14 dates have been extensively tested against other dating methods to determine what readings correspond to what time periods. One source of information on the proportion of c14 in the atmosphere are the air bubbles in ice cores. (Since c14 is a molecule, only a miniscule amount of air is needed to get a good proportional measurement.) There are also other means of figuring out the fluctuations in c14 and correcting raw measurements against these. This corrective process is known as calibration.

Since sunlight causes the formation of C-14 in the atmosphere, and normal radioactive decay takes it out, there must be a point where the formation rate and the decay rate equalizes. This is called the point of equilibrium. Let me illustrate: If you were trying to fill a barrel with water but there were holes drilled up the side of the barrel, as you filled the barrel it would begin leaking out the holes. At some point you would be putting it in and it would be leaking out at the same rate. You will not be able to fill the barrel past this point of equilibrium. In the same way the C-14 is being formed and decaying simultaneously. A freshly created earth would require about 30,000 years for the amount of C-14 in the atmosphere to reach this point of equilibrium because it would leak out as it is being filled. Tests indicate that the earth has still not reached equilibrium.

This is nonsense. It has no relevance to c14 dating at all. c14 dating has nothing to do with any "equilibrium" of c14 in the atmosphere.

The rationale behind c14 dating is this:
while plants and animals live, they take in carbon in various ways, including the carbon dioxide of respiration. Terrestrial plants and animals take in most of their carbon through respiration. Aquatic and marine animals use other sources of carbon as well. This is why c14 cannot be used reliably on shellfish, fish or marine mammals whose diet includes these. Only material from organisms whose main source of c14 is the atmosphere are good subjects for c14 dating.

Any carbon taken in from the atmosphere will have the same ratio in a living organism as in the atmosphere itself. This will be the ratio of c14 to c12 when the plant or animal dies.

Upon death, the plant or animal ceases respiration and takes in no new atmospheric carbon. From this point on the change in c14/c12 proportion is due to the decay rate of c14. Half of the existing c14 will disappear in 5730 years. Half of the remainder will disappear in the next 5730 years, and so on until the amount remaining is not measurable.

The only relevant measure is the proportion of c14 to c12 in the organism itself. This has nothing to do with any planetary equiilibrium of atmospheric c14.

There is more C-14 in the atmosphere now than there was 40 years ago.

This is irrelevant. It is not how much c14 there is that matters, but how much compared to the normal c12. The proportion, not the gross amount, is the crucial factor.

However, 2 significant factors have affected the proportion of c14. The first is the increased use of fossil fuels. Fossil fuel use introduces lots of old carbon (already depleted of c14) into the atmosphere. This makes organisms appear older than they are because the proportion of c14 is too small. The second is the atmospheric tests of the 1950s and 60s. These pumped large amounts of radioactive material, including c14 into the atmosphere. This makes organisms appear younger than they are because the c14 levels are too high. Since all organisms are affected by both these events, no readings for recently deceased organisms are considered reliable.

This would prove the earth is not yet 30,000 years old! This also means that plants and animals that lived in the past had less C-14 in them than do plants and animals today. Just this one fact totally upsets data obtained by C-14 dating.

Actually, as noted above, this has been accounted for, and the fact does not upset data for any but recently deceased (i.e. in the last 50-60 years) organisms.

They are, obviously, assuming the amount of carbon-14 in the atmosphere has always been constant, and its rate of decay has always been constant.

Again, the amount of c14 is not relevant. It is the proportion of c14 to c12 that gives the date. The proportion is related to the decay rate.

That the decay rate is constant is not an assumption. It is a conclusion from observation. Scientists made many attempts to force a change in the decay rate, not only for c14 but for other radioactive materials as well. No force (heat, pressure, magnetism, etc.) normally found on earth has been found capable of affecting the decay rates of radio-active elements. That is a consistent observation. Therefore it is concluded that the decay rate has been constant for its use in dating events in earth history.

Since this is as true of the long-live radio-active elements as it is of c14, the measured age of the oldest terrestrial rocks is over 3.5 billion years. Moon rocks have been measured to 4.5 billion years of age. So while c14 doesn't show the earth is millions of years old, other reliable radiometric measurements show it is thousands of millions of years old.

Similarly, scientists do not know that the carbon-14 decay rate has been constant.

On the contrary, they do know. At least they know that all the evidence points to a constant rate of decay.

This may be tied in to the declining strength of the magnetic field.

Another straw man, for another day.

 

[RenHoek]

Thank you for your perspective. I may throw out more in new threads for refutation.

 

[rmwilliamsll]

This corrective process is known as calibration.

This is a big deal.
First it shows how errors in science can be corrected.

Second, it is one of the items that make me believe that AiG and the leading edge of YECism are knowingly lying. Calibration is a well known issue, yet consistently YECists who ought to know better use the amount of C14 in the upper atmosphere to try to refute the dating.

If you don't understand the issue on calibration it is a worthwhile issue to spend some time reading about. The original work was with dendrochronology but ice cores and coral layers are now being used in much the same way, i suspect that the pollen in lake varves will be as well, but as yet have not found papers on this.

 

[Chief117]

Any carbon taken in from the atmosphere will have the same ratio in a living organism as in the atmosphere itself. This will be the ratio of c14 to c12 when the plant or animal dies.

This is exactly why you are wrong. This is why it is VERY important to note the ratio of C12:C14 when the test subject was alive--the "reference" point (0 years, meaning time of death) can only be calculated when the original ratio is known.

You have to use assumptions when determining that original ratio--and this is why all of the radiometric dating methods are faulty. They are impossible to be reliably calibrated.

 

[rmwilliamsll]

This is exactly why you are wrong. This is why it is VERY important to note the ratio of C12:C14 when the test subject was alive--the "reference" point (0 years, meaning time of death) can only be calculated when the original ratio is known.

You have to use assumptions when determining that original ratio--and this is why all of the radiometric dating methods are faulty. They are impossible to be reliably calibrated.

the ratios are known and plotted. the calibration/correction of raw C14 data works.

but more interesting than this error, is the idea that ALL radiometric dating is suspect since this poster doesn't understand C14/C12 ratios. Other dating does not use these ratios at all and are not effected by any problems perceived in C14 dating. yet because of YECists ideological radical polarization (either YEC or atheism), discredit any piece of data makes everything proven wrong, interesting idea, but logically incompetent.

 

[gluadys]

This is exactly why you are wrong. This is why it is VERY important to note the ratio of C12:C14 when the test subject was alive--the "reference" point (0 years, meaning time of death) can only be calculated when the original ratio is known.

You have to use assumptions when determining that original ratio--and this is why all of the radiometric dating methods are faulty. They are impossible to be reliably calibrated.

The original ratio is known from various independent sources. It does not need to be assumed. If the calibration was not reliable c14 dates would not be consistent with dates obtained by other means. But they are when properly used.

 

[Chief117]

the ratios are known and plotted. the calibration/correction of raw C14 data works.

The original ratio is known from various independent sources. It does not need to be assumed. If the calibration was not reliable c14 dates would not be consistent with dates obtained by other means. But they are when properly used.

There is no way the ratios could be known for all points in history. The ratio is definitely not the same, and there is no reason to assume that it could possibly be plotted or known--no one has recorded them.

Many things could have changed throughout history--and many flood models predict a drastic change in the ratio. The models predict that this C14 dating method would yield much older dates than would be true.

but more interesting than this error, is the idea that ALL radiometric dating is suspect since this poster doesn't understand C14/C12 ratios. Other dating does not use these ratios at all and are not effected by any problems perceived in C14 dating. yet because of YECists ideological radical polarization (either YEC or atheism), discredit any piece of data makes everything proven wrong, interesting idea, but logically incompetent.

I love the old "you're an idiot" handle on arguments. You take me out of context. I never said any other dating methods use the C12/C14 ratio--and no Creationist/YEC would ever. So don't build strawmen arguments.

My comment was in regards that all radiometric dating methods rely on the knowledge that the amount parent material (whatever that may be) is known.

Since it is impossible for you to know this, you have to make assumptions. Since your dating methods are ALL built on similar assumptions, they are fallible insofar as your assumptions are no good.

There are countless examples of all of the radiometric dating methods failing. I wonder how long your "eligible candidate" arguments will hold.

 

[rmwilliamsll]

There is no way the ratios could be known for all points in history. The ratio is definitely not the same, and there is no reason to assume that it could possibly be plotted or known--no one has recorded them.


that is exactly what tree rings and ice cores and coral layers are, a record of the C12/c14 ratios.

but more interesting than this error, is the idea that ALL radiometric dating is suspect since this poster doesn't understand C14/C12 ratios. Other dating does not use these ratios at all and are not effected by any problems perceived in C14 dating. yet because of YECists ideological radical polarization (either YEC or atheism), discredit any piece of data makes everything proven wrong, interesting idea, but logically incompetent.

I love the old "you're an idiot" handle on arguments. You take me out of context. I never said any other dating methods use the C12/C14 ratio--and no Creationist/YEC would ever. So don't build strawmen arguments.

My comment was in regards that all radiometric dating methods rely on the knowledge that the amount parent material (whatever that may be) is known.

and no, all radiometric dating techniques do NOT require a knowledge of parent material ratios or ratios in the form of C12/C14. in fact, this kind of ratio is pretty rare in the overall scheme of radiometric dating.

it is not a strawman, to logically align original C12/C14 ratios with parent material and therefore to discredit all radioactive dating techniques is a misunderstanding of the fundamental science of the field. You are making an analogy between the techniques of C12/C14 dating and all other radiometric dating that does not exist. But more importantly you are trying to discredit all radioactive dating from a fundamentally erronous idea of how C14 dating works.

i did not use the term idiot, nor did i use any similar name calling, this is your idea and/or impression. i do not argue in that manner.

 

[Assyrian]

Technically he does have a point, though it is the ratio of parent to daughter isotopes when rock formed than simply the amount of the parent isotope. However this can be calculated quite accuratly using isochrons.

 

[gluadys]

There is no way the ratios could be known for all points in history. The ratio is definitely not the same, and there is no reason to assume that it could possibly be plotted or known--no one has recorded them.

But they have been recorded for the last 50,000 years. Including the changes in ratio.

Many things could have changed throughout history--and many flood models predict a drastic change in the ratio. The models predict that this C14 dating method would yield much older dates than would be true.

Changes in the ratio are irrelevant to dating. Once you know the initial ratio, it is the rate of decay that gives the date.

I can see why you reject the possibility that the ratios of the past can be recorded. That allows you to hide behind apparent ignorance to make an unsubstantiated claim of a drastic change in ratio at a specific point of history.

Since c14/c12 ratios can be and have been recorded, you ought to be able to show this drastic change in ratio from the established records.


It's not there, right?

 

[rmwilliamsll]

Technically he does have a point, though it is the ratio of parent to daughter isotopes when rock formed than simply the amount of the parent isotope. However this can be calculated quite accuratly using isochrons.

From past experience and from some of the things posted by YECists here, both on this thread and in the past, i believe that the common misconceptions about C14 dating is that it is like many other radiometric dating processes where the ratio is for mother/daughter products.

I'd just like the YECists to put enough actually scientific knowledge into their postings so that we can see if they actually understand that C14 and C12 are not mother/daughter products and that the ratios C14/C12 when creature died versus C14/C12 ratio today is technically different from the current K40/Ar40 ratio in a rock sample.

My big point is that trying to discredit radiometric dating as a principle because the C14/C12 atmospheric content as changed over the last 50K years(it has pretty constantly increased over longer time intervals) is usually a great misunderstanding of the C14/C12 as a mother/daughter product ratio in the same way as K40/Ar40 is.

 

[Robert the Pilegrim]

The amount of carbon 14 in the atmosphere today (about .0000765%), is assumed there would be the same amount found in living plants or animals since the plants breath CO2 and animals eat plants. Carbon 14 is the radio-active version of carbon.

This is not correct.

However, it is worthwhile to note, that that assumption was made in the 1950s (into the early 60s?).
Scientific testing showed it to be a faulty assumption.

It is known that the amount and proportion of C14 varies over time. C14 dates have been extensively tested against other dating methods to determine what readings correspond to what time periods. [] This corrective process is known as calibration.

[Leaky bucket analogy]

This is nonsense. It has no relevance to c14 dating at all. c14 dating has nothing to do with any "equilibrium" of c14 in the atmosphere.

I would beg to quibble.

It is an application of logical analysis with insufficient knowledge.

If the data did not rather clearly show that C14 production has varied over time, the Hovind's argument would make sense.

But the data does show that, and Hovind's argument is
moot.

This is why c14 cannot be used reliably on shellfish, fish or marine mammals whose diet includes these. Only material from organisms whose main source of c14 is the atmosphere are good subjects for c14 dating.

Care must be taken, but aquatic and marine animals can be dated with C14.

Any carbon taken in from the atmosphere will have the same ratio in a living organism as in the atmosphere itself. This will be the ratio of c14 to c12 when the plant or animal dies.

Upon death, the plant or animal ceases respiration and takes in no new atmospheric carbon. From this point on the change in c14/c12 proportion is due to the decay rate of c14. Half of the existing c14 will disappear in 5730 years. Half of the remainder will disappear in the next 5730 years, and so on until the amount remaining is not measurable.

 

[Robert the Pilegrim]

I am no scientist. Please explain from an evolutionary standpoint. Lay terms would be helpful.
From: http://www.drdino.com/articles.php?spec=73

[Scientists] are, obviously, assuming the amount of carbon-14 in the atmosphere has always been constant, and its rate of decay has always been constant. Neither of these assumptions is provable or reasonable.
​

The thing about scientists is that sooner or later one of them will say, "Is that really the right way to do it?"

And then they go out and look at the existing data, and if it isn't truly convincing, they start doing experiements.

The physics of C14 decay and of light production is very closely related.

If the decay constant for C14 changed at some point in time one would expect light to have changed at the same time.

The Milkyway galaxy is roughly 80,000 in diameter. If you look at a star 8 light minutes away, or 4 light years away or 4000 light years away or 60,000 light years away or anywhere inbetween, the light all looks the same.

If you want to know what it means for light to look the same, read up on hydrogen spectra, blackbody radiation, absorption spectra. There are lots of ways to look at light, to examine how it was produced. Detailed explanations are available in a good physics text. (I suspect there are some decent web pages around as well.)

The Supernova SN1987A was observed in 1987 in a "nearby" galaxy 170,000 light years away.

The spectra of various elements (radioactive and otherwise) created in the supernova were as expected, and the half lives of various radioactive elements created in the supernova were as expected.

The short answer is that there is a very substantial body of evidence that decay rates have not changed, and no evidence that they have.