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Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: |
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Author | Topic: Age Correlations and an Old Earth: Part II. | |||||||||||||||||||||||||||||||
TheLiteralist Inactive Member |
Hi RAZD,
Right now, I am sick with some flu-like thing (and hopefully I am on the mend). I am also in the middle of a couple of projects (I have a little sign manufacturing business I run on the side of making biscuits for Hardees). So please forgive me if I am somewhat slow responding to your first post ("Watch that first post, it's a doozy" ~ to bend a cliche a bit ). Seriously, though, your first post is long and full of information and supporting links. I haven't made it through even once, yet. I shall probably need to go through it twice before I can discuss it with any sort of intelligence. But I do appreciate the fact that the thread has been re-opened almost purely for my posting benefit (not that others can't post, too, of course), and I didn't want you or NosyNed or AdminJar et al. to think that I am ignoring the thread. Thanks. P.S. ~ another bulletin board I visit with some regularity ~ Letterville Bullboard ~ uses ipop, too, and their threads can be printed (but the format has to be changed to "printer-friendly"). I don't know what such a feature would mean in terms of costs v. benefits for this forum, though. Added by edit:I'm afraid that varve, tree-ring, and coral dating techniques, while I have certainly heard of them, I haven't studied them from either viewpoint (i.e., that of the creationists or evolutionists). So, I'll be delving into an area in which I have no familiarity...I will be quite slow, as I might wish to study these techniques (well, I won't be getting a degree on them) a bit, too, outside of the information and links you provide on the subject. Thanks again. This message has been edited by TheLiteralist, 12-06-2004 11:55 AM
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TheLiteralist Inactive Member |
Sorry, I'm missing something obvious I'm sure.
What does the phrase "cal. yr. B. P." mean? I get calendar year from cal. yr., but I have no clue what B. P. means. I believe it is mentioned in your OP about Lake Sugietsu (or whatever) and at this link. Thanks. This message has been edited by TheLiteralist, 12-06-2004 06:43 PM
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TheLiteralist Inactive Member |
Hi JonF,
Before Present? Simpler even than I imagined . Thanks.
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TheLiteralist Inactive Member |
Hi RAZD,
In regards to this article... What is the procedure used to calibrate the C14 method by the varve method? I know they carbon date (determine the C14/C12 ratio, right?) a sample fossil from a varve. I know they determine the age of the sample fossil's varve by counting. So, the fossil has a varve age and a carbon age, of course. But do you (or someone else) happen to know the *procedure* by which the carbon age is calibrated by the varve age? (Does the article say, and I'm just missing it?)
The article says: ...we estimated the varve chronology of older than 20,000 yr B.P. (19-m depth of SG core) by counting in a single core section, the error of the varve counting increases with depth, and the accumulated error at 40,000 cal yr B.P. would be less than 2000 years, assuming no break in the sediment. So, every varve age should be given in a range (e.g., 12,000 years B.P. +/- 2000 years), right? Which means the C14 age, which the varve age is calibrating, cannot be any more precise than to give an age within a 4000 year range (+/- 2000 years), right?
The articles says: These data suggest that 14C dates at this time are 5000 years too young. This discrepancy can be caused either by speleothem dating problems (such as unknown initial 14C age and possible detrital Th contamination) or missing varves in the older section of Lake Suigetsu. In this study, are the initial C14 ages of the fossils in the varves known? I understand that the present ratio between C14/C12 (or whatever) can be measured, but how does one determine the *initial* C14 age of a given sample? Are they suggesting that their original 4000 year range ( +/- 2000 years) for any given varve might be a 10,000 year range (+/- 5000 years) in some cases? Also, a little Googling on diatoms makes me think that to assume a once-a-year diatom layer is a bit simplistic. Diatom blooms, apparently, are affected by nitrogen, ammonium, phosphate (all common plant-fertilizer ingredients, btw) and silicate levels in the water as well as by the amount of sunlight they receive. (Check out this article: Florida Bay Watch Report: the Plume and the Bloom) Did these guys do a separate, detailed study on the present conditions that could affect diatom activity in this lake? Or, did they, perhaps, refer to such a study of this lake? Considering the variables involved in diatom activity (and I never was able to find information on possible common sources of massive diatom destruction {a statement that could be misleading removed by TheLiteralist}), how is it reasonable to assume these varves form annually in the present? Considering the variables involved in diatom activity, how is it reasonable to assume that the varves have been forming annually every year for the past 20,000 or 40,000 years? This has been quite challenging, BTW. I haven't even gotten to the other things...I'm still stuck on lake varves. Thanks. This message has been edited by TheLiteralist, 12-11-2004 06:26 AM
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TheLiteralist Inactive Member |
I don't know if this adds anything to the discussion or not, but, according to an online Smithsonian Magazine, diatoms live about 6 days. (Seems like a rather short life span to me).
Even if it doesn't enter into the discussion, it's cool to know.
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TheLiteralist Inactive Member |
Hi RAZD,
Sorry, I'm still having trouble understanding this calibration thing. For the moment, I am not concerned with the validity of the calibration method, but presently I am trying to understand HOW the calibration works in some detail (I emphasize: don't worry about whether or not I see these timing methods as valid). This graph, in particular, is incomprehensible to me:
What do these data points represent exactly, and how were the data points on this graph obtained?
{This question added via edit by TheLiteralist}Also, just like in graph B of that Lake Suigetsu article, this one has different starting points and scales for each axis. Why? And then about this graph:
Since the varves and tree-rings are assumed to be annual, shouldn't they {typo removed by TheLiteralist} automatically line up with the actual time line (the nice, straight, diagonal line) And since the C14 ages are set equal to the varve and tree-ring ages, shouldn't the C14 ages also be equal to the nice, straight, diagonal time line? I don't understand the how the data could deviate at all from the time line, and if they do, it would be a problem in the varves or tree-rings because you say the C14 ages are simply set equal to the varve and tree-ring ages. What am I missing? I feel like I am overlooking something obvious here. I think the answer to these questions will help my understanding of the process of calibration tremendously. On the other hand, it might not help me at all. But I think it's a good starting place, nonetheless. Thanks. This message has been edited by TheLiteralist, 12-13-2004 04:51 AM This message has been edited by TheLiteralist, 12-13-2004 04:56 AM
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TheLiteralist Inactive Member |
Hi RAZD,
Yes, my questions are about calibration because I am ignorant of this process and it seems to underlie the correlation issue, which I also am ignorant of. The calibration thing seems somewhat technical. Thanks for this particular reply. You've put quite a bit of work into it, but I'll need some time to digest it.
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TheLiteralist Inactive Member |
Hi Craig,
Thanks for your response; I certainly appreciate your input and shall consider it. The thing about waves and varves is interesting to me. Stick around if you like. I don't know if there are any explanations for these phenomena from a Noah's Flood view point that I can access (whether due to availability of information or due to ability of my mind). However, I am going to give a good try to understand this issue as much as I can (there is a limit, of course, due to my having other things to do and such and/or going blind due to staring at a computer screen for hours on end).
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TheLiteralist Inactive Member |
Hi NosyNed,
Just didn't want you to think I'm ignoring you. For some reason, I tend to address mainly RAZD on this thread...I guess because it's his OP that has me hunting and fishing and trying to understand calibration and such. Anyway, I AM reading you. BTW, you said:
quote: No, I mean that +/- 2000 years is a 4000 year range, but it can get knotty to understand sometimes exactly what I mean. I got it about the percentage thing though (or the error increasing with the count).
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TheLiteralist Inactive Member |
Everybody seems to be being cool and detatched (pretty much, anyways). That's good.
I just wanted to point out that, unless I missed something (very possible), I don't think Craig ever once said that the bacteria were selectively eating 14C instead of 12C. What he seems to think, rather, is that since bacteria are eating the kerogen (or leaves in the varves in Lake S.) the 14C/12C ratio is somehow being affected. Looking at ratios alone, this idea would be just incorrect. However, I won't go so far as to say that bacteria actions do NOT affect 12C/14C ratios at all (in either direction); it does seem counter-intuitive, however. As far as the different weights of the two isotopes are concerned, this flashed through my mind briefly, but I quickly realized this would make the ages go the wrong way (i.e., carbon ages would get younger with depth) ~ and then I read PaulK's post which says basically the same thing.
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TheLiteralist Inactive Member |
PaulK,
I can certainly see how one could think Craig was trying to imply selective eating, but I really don't get that when I read his posts. For instance, in the post you link to he simply says that the bacteria eat 14C, and they do. In the next post (#108), he tells Loudmouths that the bacteria eat the 14C before it converts to 12C, and they do. Neither time has he claimed that the bacteria are selecting 14C instead of 12C. Also, if you will read some of the dialog between Craig, Crashfrog and Loudmouth, I think you will find that Craig is claiming that the bacteria are eating both and that this upsets the ratio somehow. Crashfrog and Loudmouth both try to teach Craig about how ratios work in response to his claims. Now I think Craig knows how ratios work, but then we have what are apparent ponderings on his part about the 14C or 12C bonding to objects in overlying layers and such. He does not seem too dogmatic (to me, anyways) about these ponderings. I repeat, however, that I can see how one could think Craig had implied selective eating ~ that's why I wanted (to try to) clear it up a bit.
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TheLiteralist Inactive Member |
PaulK,
Well, I hope you don't think I was "picking on you." I meant no disrespect (just in case I came across that way), it's just that the way you were interpreting him led you to the conclusion that he was being dishonest. It was certainly easy enough to think Craig was implying the "selective eating" idea (I think at first Loudmouth also thought Craig meant that), and that's why I wanted to point out that he didn't actually imply that idea it just really looked like he did. Craig certainly may have misread the article. As a matter of fact, Craig mentions them feeding "new" shale to the bacteria, but I think he has mistakenly thought that's what they meant when they said "New Albany shale"...if he did, that's worth a small chuckle, I think; I occasionally make mistakes like that. I don't know if the idea of bacteria affecting 14C/12C ratios is realistic or not...it's the first time I've ever heard of such an idea. Craig has seemed rather to be in a "pondering" mode on this issue, I think. I consider the idea interesting, but I'm not going to get excited about it right now. Anyways, I also didn't mean to be a bother about this either...so, "nuff said"...right?
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TheLiteralist Inactive Member |
NosyNed,
Except for Craig thinking you are a lurker (psst: Craig, NosyNed is a long-time memeber with a VERY good reputation with this forum), I've enjoyed much of his input and the related discussions. But I do recognize the issues you bring up (which, of course, is the whole point of the thread). Hopefully, I will be able to do the in-depth reading (of RAZD's opening post and links and one of RAZD's posts that goes into some detail about carbon dating over the next two or three days...I might still have questions about carbon dating and calibration after that but I want to do the reading first).
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TheLiteralist Inactive Member |
Coragyps,
Cool. That sounds very interesting. I'm afraid chemistry wasn't my best subject; so, while I'll be very interested in seeing a technical explanation, I might have trouble understanding it (i.e., I might need clarification here or there). BTW, what is "fractionation"?
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TheLiteralist Inactive Member |
RAZD,
Am I looking at this graph correctly now?
How I'm seeing it now... Each data point represents a fossil from a lake varve. The bottom line (independant variable) is the varve "age", which is generally OLDER than the carbon age (vertical axis, dependant variable) and apparently in a fairly consistent way. THAT'S how they are able to have different starting points on the two axis ~ it's two different "ages" for the same sample! (I got it, right?) Now about THIS graph:
What I DO get...(I think)The horizontal axis (independent variable) represents the "absolute ages" as determined by either varve count, tree-ring count, or ice-layer count for various samples. The vertical axis (dependent variable) represents the (calibrated?) "carbon age" of the same various samples. What I DON'T get... If the varves are assumed annual, then the varve ages should either be THIS diagonal line or an off-set but parallel line, right? Are there flucations in the varve ages? Since the 14C ages are "calibrated" by simply setting them equal to the varve "ages", then I fail to see how any variables affecting 14C "ages" comes into play in this second graph. IS this graph using calibrated 14C ages? I'm assuming it is. It just seems that once you've set something equal to something else, the 1:1 ratio automatically exists...if these are "calibrated" carbon ages, I don't understand the deviation from a 45-degree line. I'm still not getting this graph. Or does the line represent "calibration" and the points and their deviations are just the other graph on a different scale? Please note, that I am setting aside, temporarily, all the young-earth/old-earth issues and granting the researchers all their assumptions; I am NOT trying to disprove anything in this post; I am simply trying to understand their graph. (I think I finally got that first one...whew!)
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