Thursday, March 26, 2015

How Old is Old? – Part I

Will Rogers, the American cowboy of the late 1800s and  humorist once said, “Laws are like sausages; you don’t want to see them being made.” This saying was first attributed to Otto von Bismarck, the celebrated German statesman of the 19th century, who said, “There are two things you don’t want to see being made—sausages and legislation.” In a spinoff of this saying, actor Leo McGarry of “The West Wing” TV series stated: “There are two things in the world you never want to let people see how you make 'em - laws and sausages.” Even the food industry itself has copied the phrase:  “There are two things you don’t want to watch being made: sausages and laws.” In fact, the early science-fiction author and associate editor of Fortune Magazine, put it this way in the early 1900s: “Profits, like sausages, are esteemed most by those who know least about what goes into them.”
Left to Right: Will Rogers, Otto von Bismark, and Les McGarry
    Obviously, the saying has been around for some time, but I think a more accurate saying today is “There are three things people know little about—how sausages, laws, and radiocarbon dates are made.”
    It is interesting that in the scientific world, the dating of Carbon-14 is considered, without a doubt, the end all of knowing the dates of once living and now dead things. It is based on the carbon cycle and how much Carbon-14 remains in the item being dated, be it once living vegetation, charcoal, wood, bone, soil, pottery, blood residue, textiles and fabrics or animal remains. Even water can be radiocarbon dated—that is, age can also be determinated by obtaining carbonate deposits such as calcite, dissolved carbon dioxide, and carbonates in ocean, lake, and groundwater sources.
    This radiocarbon dating method was first developed by a team of scientists led by the late Professor Willard F. Libby of the University of Chicago in immediate post-World War II years, for which he received the Nobel Prize in Chemistry in 1960. It is based  upon a simple and accurate concept of Carbon-14 oxidization.
To better understand this, there are three principal isotopes of carbon, which occur naturally in the atmosphere: C12, C13 (both stable) and C14 (unstable or radioactive). These isotopes are present in the following amounts C12 - 98.89%, C13 - 1.11% and C14 - 0.00000000010%.
Thus, one Carbon-14 atom exists in nature for every 1,000,000,000,000 Carbon-12 atoms in living material. The radiocarbon method is based on the rate of decay of the radioactive or unstable carbon isotope 14 (C14), which is formed in the upper atmosphere through the effect of cosmic ray neutrons upon nitrogen 14.
    It has been said that "Seldom has a single discovery in chemistry had such an impact on the thinking of so many fields of human endeavor. Seldom has a single discovery generated such wide public interest." Unfortunately, it might also be said, “Seldom, if ever, has a single discovery created so much misinformation in so many fields of human endeavor.”
Rasmus Nyerup (left), the Danish antiquarian, once said, “Everything which has come down to us from heathendom is wrapped in a thick fog; it belongs to a space of time we cannot measure. We know that it is older than Christendom, but whether by a couple of years or a couple of centuries, or even by more than a millennium, we can do no more than guess." Unfortunately, while we are no longer guessing, we are coming up with the wrong answers! The reason for this is simple—we have set the dating clock wrong! And not just anyone, but the inventor himself set it wrong!
    The problem arises not from the concept, or even the understanding of it, since both are based on correct principles; however, the error exists because of the simple interpretation of the data provided. To understand this, it is important to know that Carbon-14 once formed rapidly oxidizes to Carbo-14CO2, and enters the earth’s plant and animal life through photosynthesis and the food chain.
    The rapidity of the dispersal (elimination) of Carbob-14 into the atmosphere has been demonstrated by measurements of radioactive carbon produced from thermonuclear bomb testing. Carbon-14 also enters the Earth's oceans in an atmospheric exchange and as dissolved carbonate (the entire Carbon-14 inventory is termed the carbon exchange reservoir). Plants and animals which utilize carbon in biological food chains take up Carbon-14 during their lifetimes.
    The important thing is that this carbon-14 exists, both within the living thing and the atmosphere in what is called equilibrium—the equal balance of Carbon-14 in both entities (the living thing and the atmosphere), that is, the numbers of Carbon-14 atoms and non-radioactive carbon atoms stays approximately the same in both over time as long as the living thing is alive.
    It is also important to know that as soon as a plant or animal dies, they cease the metabolic function of carbon uptake (intake); there is no replenishment of radioactive carbon, only decay within the once living thing. And this rate of decay can be measured! Libby and his associates Ernest Anderson and James Arnold, were the first to measure this rate. At first they got it wrong, using the figure 5,568 years, which became known as the Libby half-life. Today, we now know this to be 5,730 years.
    This means, that no matter how much Carbon-14 a living thing had at death, exactly one-half of it would be gone in 5,730 years after its death.
In this diagram we can see that each 5,730 year cycle, one-half of the existing Carbonb-14 oxidizes (is converted to Carbon-12. All that is needed is to know is how much Carbon-14 existed in a living thing at the time of death, then measure it against what is left at the time of measurement, and the time elapsed can be determined
    There are a few assumptions that have to be made in order for this concept to be accurate, however, the idea is based on a correct understanding of the decay rate of Carbon-14.
    The major obstacle to this so-called “clock” to work is that the state of Carbon-14 in the atmosphere must be understood, i.e., is that state in equilibrium (has the build-up of Carbon-14 in the atmosphere reached an equal amount or balance with its decay) or non-equilibrium (is Carbon-14 still building up in the atmosphere at a greater rate than its decay). And to know that, it must be determined how old the Earth is to begin with—at least in a plus or minus state of about 40,000 years. Stated differently, if the Earth is over 40,000 years old, then the build up of carbon in the atmosphere has reached a state of equilibrium, i.e., for every amount of build-up, there is an equal amount of decay (dissipation): the Earth is in equilibrium. And since it takes around 40,000 years for that equilibrium to be achieved, the “clock” is set either to an equilibrium state or a non-equilibrium state. That is, if the Earth is less than 40,000 years old, there is still build-up taking place in the atmosphere.
    Considerate like a glass of water. It takes so much to fill the glass and once that is achieved, you have equilibrium—any more water poured into the glass simple spills out because the glass can hold no more. And once equilibrium is achieved, you know that no more room is within the glass (or the living thing) to acquire or absorb more or additional water (Carbon-14). In this way, then, a correct determination can be made as to the age of the item being tested since no more Carbon-14 can be absorbed into it.
    The problem lies, once again, with the point of equilibrium. Or stated different, how old is the Earth to begin with?
Carbon-14 enters the atmosphere when cosmic rays bombard the earth’s atmosphere, producing neutrons. These excited neutrons then collide with nitrogen atoms in the atmosphere, changing them into radioactive carbon-14 atoms, which in turn are absorbed by all living matter. Once the living thing dies, the Carbon-14 dissolves at the rate of 5,730 years per half life (half of the Carbon-14 decays in 5,730 years)
    To point out the importance of this, take a state where equilibrium exists. Once the living thing dies, no more Carbon-14 is entering the atmosphere (it is in a state of equilibrium) so no more can enter the animal or plant life that has died, so the markers or decay rate of Carbon-14 can be accurate measured. However, and this is a big “however,” if the Earth is not in equilibrium, then when the living thing dies, additional Carbon-14 will enter the dead animal or plant life as it continues to build up in the atmosphere, thus, any measurement will show an incorrect figure or age.
    It is like not setting your clock ahead for Daylight Savings Time. Your clock will be one hour behind. It will always give you the correct time—one hour behind—no matter when you check the time. And it will always be wrong—one hour behind. It is not that the clock does not work—it is that it is set to the wrong time and will always be wrong!
    So how did Libby’s time clock get set to the wrong time?
(See the next post, “How Old is Old? – Part II,” to see how and why Libby’s clock was set to read the wrong time for radiocarbon dating and what impact that has on our understanding the past and the age of the Earth, and more importantly, the effect this has on the dating of artifacts and ruins found in the Americas in determining at what calendar date they existed--the importance of which cannot be overstated since it is these dates that we come to understand when the Americas were first occupied and how and by whom)

7 comments:

  1. This comment has been removed by the author.

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  2. This comment has been removed by the author.

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  3. The counter that I have seen most often is that equilibrium has been reached, but that because of fluctuation in cosmic rays, there are natural (though minor) fluctuations in the amount of Carbon 14.

    (Original post deleted and typo corrected)

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  4. "if the Earth is not in equilibrium, then when the living thing dies, additional Carbon-14 will enter the dead animal or plant life"

    This does not make sense to me. The entire foundation of Carbon-14 date measurement is that once dead, no additional Carbon 14 enters the organism.

    How does increasing atmospheric Carbon-14, cause an increase in Carbon-14 in non-living organic matter?

    If you are claiming there is some kind of diffusion because of a differential between the atmosphere and organic remains, then Carbon-14 in organic remains would always receive an increasing influx of new Carbon-14 as the original Carbon-14 decayed.

    This would totally invalidate any use of Carbon-14 as a dating method regardless of whether atmospheric Carbon-14 is in equilibrium.

    (Original post deleted to more clearly note the quote)

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  6. I apologize for the mess of these posts.

    The first was a minor their/there error that I probably should have left.
    The second had the original quote run into my comments which appeared confusing.
    The final one was a duplicate of the second correction that I somehow double-posted.

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  7. No problem for the deletes. For whatever it is worth, I have found writing my comment first, then pasting it into the box here works best for me--that way any mistake can be corrected before actually posting it.

    As for your comment, you have hit on the problem with Carbon-14 dating. Let me explain this in a later response where I will have more room to explain it--but your point is well taken and exposes the entire issue many of us have with C-14 and Libby's "clock," which reads the wrong dates, and does so exponentially as one goes further back in time. That is why we have the early B.C. dates for some of the Nephite ruins covered in the previous several posts covering early Peruvian cultures.

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