|
Register | Sign In |
|
QuickSearch
Thread ▼ Details |
|
Thread Info
|
|
|
Author | Topic: Request for Carbon-14 Dating explanation | |||||||||||||||||||||||
Rick Rose Inactive Member |
Ned, I was merely replying to the mathamatical model of post 57. Message 57
His model for a young atmosphere, as he stated could only work like an anuity if the model is as stable as an anuity. I was merely pointing out that radiocarbon input output is not stable for the purpose of replying to his model. Hence his calculation of a 13,600 yr atmosphere would be hard pressed. rickrose This message has been edited by Rick Rose, 05-11-2004 11:28 PM This message has been edited by Rick Rose, 05-11-2004 11:29 PM
|
|||||||||||||||||||||||
NosyNed Member Posts: 9004 From: Canada Joined: |
Sorry I jumped in without catching up carefully.
|
|||||||||||||||||||||||
Rick Rose Inactive Member |
There are also other factors that can change the ratios such as past sea levels. Where did this come from? What other factors? How do past sea levels change the C-14, c-12 ratio? You criticize the thought that sea levels can alter c-14 constants. I know that I have a lot of study to do, but so do you. The ocean is earths greatest carbon 12 reservior. Altering It's volume can alter the syncronization of our radioactive clock. This issue goes back as far as the uppsalla conference. I'm suprised you haven't stumbled upon it by now. How about fluctuations in earths magnetic field. As the field intensifies, fewer cosmic rays penetrate atmosphere, lowering c-14 production. As the field weakens the opposite occurs - more c-14. I'm quite sure all these subjects have been discussed on evc. Ned, follow the thread back to 57. See that I was merely responding to something totally different than you assumed -- lighten your load. rickrose
|
|||||||||||||||||||||||
Rick Rose Inactive Member |
Sorry, I responded without seeing that you jumped.
good nights rest rickrose
|
|||||||||||||||||||||||
Rick Rose Inactive Member |
Message 47
It would be great to have a thread dedicated to dendrochronology - not simply that a calibration has been made, but a real discussion about how the calibrations were made. Everywhere I look, I see the dendro calibration implication. Not once have I found how the calibrations were caried out. I have found sites that may require a degree in chemistry, math and physics to understand, but how about a discussion of a-z about how all the calibration has been achieved - not throuth lake varves or ice, but for now through trees. RAZD, your response is:
sorry, I have a link on my thread about age correlations (http://< !--UB EvC Forum: Age Correlations and an Old Earth -->http://EvC Forum: Age Correlations and an Old Earth -->EvC Forum: Age Correlations and an Old Earth< !--UE-->) in the section on the oak tree ring data that gives a pretty good overview of the process of dendrochronology: Useful Tree Species for Tree-Ring Dating including some of the problems encountered. I just read those articles sited in your links and the one about a year without a summer, and they do not adress the mechanisms of dendrochronology calibration. How about a discussion the a-z of calibration. It's just not to be found. rickrose This message has been edited by Rick Rose, 05-12-2004 12:56 AM
|
|||||||||||||||||||||||
RAZD Member (Idle past 1436 days) Posts: 20714 From: the other end of the sidewalk Joined: |
I have a feeling we are talking past each other with views based on assumptions not expressed.
Let's take it down a notch and see? Dendrochronology is based on the concept of counting annual rings of growth in many 'signature' tree species, from European oak to California bristlecone pine. This is based on the assumption that one ring, composed of fast summer growth and slow winter growth, is easily discernable and that it represents an actual year of growth. The first step in establishing such a system is to verify that the data is accurate, that the rings are in fact annual, and that there are not significant factors that can cause false data. Some of these factors are discussed on the tree ring website cited, and this is usually checked by using many more than one sample. Tree rings can be counted from cores from many trees, for instance. Climate changes cause differences in the growth rates and thus in the size of the annual rings, and these can be used to check from one sample to another to see if there is a consistent pattern of growth. This climate data can also be used to extend the chronology from living trees to recently dead samples and eventually even to fossil trees, but there needs to be sufficient numbers of samples with plenty of overlap so that pieces can be aligned and the data repeated. Think of the climate pattern as the fingerprint of the tree rings. This is one level of calibration. Sources and frequencies of errors give you the accuracy of the system in (+/-)%. The second step is correlations with other tree ring systems to see if the data matches on climate: some years are better for growing than others, and the patterns of growth show variations in climate in the size of the tree rings. Other checks are marker events, like the "year without a summer" or wood buried by Pompeii or in Egyptian tombs of known dates, that show up at the correct place for annual growth rings to match the historical records. Climate is global, and the data shows similar trends around the world, from oaks in Europe to pines in California. This is another level of calibration. When a piece of wood is dated using Dendrochronology the ‘fingerprint’ of the climate pattern is compared to the master file to find the best match, and the accuracy depends on the tree species and the size of the sample (how many rings to match). There is more information in a series of slides at:Error 404: Page or Resource Not Found | NCEI Essentially calibration comes down to verifying that the rings accurately represent annual growth. we are limited in our ability to understand by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}
|
|||||||||||||||||||||||
JonF Member (Idle past 199 days) Posts: 6174 Joined: |
How about a discussion the a-z of calibration. You might find some useful information at Henri D. Grissino-Mayer's Ultimate Tree-Ring Web Pages. Of course, once you've "counted" the tree rings, you just date each ring with C-14 and you're done.
|
|||||||||||||||||||||||
Rick Rose Inactive Member |
I do appreciate the time you took to respond to such a novice. I am trying to find a book about the radiocarbon/dendrochronology curve. I prefer books over web sites as I can follow the author at my leasure. I will look up your posted web sites.
rickrose
|
|||||||||||||||||||||||
RAZD Member (Idle past 1436 days) Posts: 20714 From: the other end of the sidewalk Joined: |
s'cool
we are limited in our ability to understand by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}
|
|||||||||||||||||||||||
SumNemo Inactive Junior Member |
Radiocarbon dating is the more popular and widely publicized form of radiometric dating. However, it has many downsides, as mentioned many times above. It is only accurate up to a point, for example. However, radiometric dating is not limited to just Carbon-14. The radioactive rate of decay of, say, uranite, the main ore of uranium, is known and immutable. This knowledge, combined with the theories of Nicolas Steno, who proposed the principles of superposition, original horizontality, lateral continuity, and cross-cutting relationships, can tell us the ages of fossilized organisms found within a section of rock, as well as the age of the rock itself.
|
|||||||||||||||||||||||
AdminNosy Administrator Posts: 4754 From: Vancouver, BC, Canada Joined: |
Welcome to EvCForum, SumNemo. We all hope you enjoy visting here.
If you haven't already please review the forum guidelines.
|
|||||||||||||||||||||||
SumNemo Inactive Junior Member |
I did nothing wrong, right? That's just a general greeting?
|
|||||||||||||||||||||||
AdminNosy Administrator Posts: 4754 From: Vancouver, BC, Canada Joined: |
LOL, no you didn't do anything wrong. It's just nice to be sure that everyone is aware of the guidelines.
If I wanted to be a real pain in the as. uh,neck I could say that other dating methods are not on topic in this thread.
|
|
|
Do Nothing Button
Copyright 2001-2023 by EvC Forum, All Rights Reserved
Version 4.2
Innovative software from Qwixotic © 2024