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Author Topic:   Age Correlations and an Old Earth: Part II.
Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 23 of 306 (166761)
12-09-2004 10:22 PM
Reply to: Message 21 by dpardo
12-09-2004 9:52 PM


Re: tree ring dating
There are studies both in Germany and Finnland that use exactly the methods Ned mentioned on logs preserved in bogs and pond bottoms. Each used hundreds upon hundreds of trees, and each goes back to about 11,000 years ago. The Grissino link given a few posts back references these and other studies, but I've never found the primary stuff on the 'net. A paper in German I could interpret ein bisschen, but Finnish, in which I think the original Finnland paper is, wouldn't speak to me very clearly.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 43 of 306 (167708)
12-13-2004 11:47 AM


Literalist - a couple of points that I'd like to add to what's been said:
If you count anything at all - presidential votes in Florida, varves, tree rings, whatever - there will be some error in your count. The error will be smallish for small total numbers, or for usually yes/no things like votes, but get larger - by the nature of the counting process itself - for numbers in the thousands where the items being counted can occasionally be "hazy" or ambiguous.
You might also note that the paper mentions about 50 samples from deeper in the core that dated as "infinite." This just means that so much of their 14C has decayed - like in 60,000 years or more - that the amount remaining is statistically the same as zero. The authors used this oldest stuff as their "background" - the zero 14C level that the measuring method gave if you really had 0.000000000% carbon 14 in your sample, and were just measuring the minute traces you picked up from, maybe, the rubber gloves that you handled the samples with when you picked them out of the core.

Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 61 of 306 (168118)
12-14-2004 1:40 PM
Reply to: Message 60 by Loudmouth
12-14-2004 12:20 PM


Re: Lake Suigetsu
The dates also include leaves and insects trapped in each of the layers,
All the dates were on terrestrial stuff like that - none on diatoms themselves.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 67 of 306 (168166)
12-14-2004 3:28 PM
Reply to: Message 64 by johnfolton
12-14-2004 3:09 PM


Re: Lake Suigetsu
How big do waves get in a 3 kilometer diameter lake, Craig?
This lake has never been within 1000 km or more of a glacier, either. You can count that out.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 130 of 306 (169369)
12-17-2004 11:43 AM
Reply to: Message 125 by Minnemooseus
12-17-2004 1:57 AM


Re: Speculations
I don't know how this process might effect 14C in the sediments.
Fractionation such as your reference talks about depends almost completely on the mass of the isotope in question - just the mass, nothg else. So a process that enriches a sediment in 13C will enrich it a little more in 14C, because it's even heavier. This phenomenon has been measured many times with oxygen, where 16O, 17O, and 18O are all stable. And sulfur, with four stable isotopes.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 131 of 306 (169371)
12-17-2004 11:50 AM
Reply to: Message 129 by johnfolton
12-17-2004 11:41 AM


Re: Speculations
Craig, you seem to be just stringing words together here.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 137 of 306 (169426)
12-17-2004 2:07 PM
Reply to: Message 132 by johnfolton
12-17-2004 12:27 PM


Re: Speculations
If C14 tends to form carbonates, and C12 tends to form CarbonDioxide.
Carbon dioxide, bicarbonate, and carbonate, though, are all the same thing. They're just the species that form when you dissolve carbon dioxide gas into water at different levels of acidity/alkalinity. They won't cre much about isotopes once in solution - perhaps there's a significant isotope effect on crossing from the air into solution, though.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 147 of 306 (169537)
12-17-2004 5:20 PM
Reply to: Message 142 by TheLiteralist
12-17-2004 3:59 PM


Re: What Craig Said
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.
Most any metabolic action on a source of carbon will lead to products with altered ratios of 12C to 14C, and, for the identical reasons, 12C to 13C. The 12:13 ratio is, in fact, used as a correction to figure what 12:14 ratio to expect in some studies. I think I have a reference at home that gets deeper into the hows and whys of this - I'll look tonight or tomorrow. But with a great amount of certainty, I'll say that the enormous selectivity of enzymes, in general, toward their substrates will and does result in big isotope fractionations.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 162 of 306 (169586)
12-17-2004 8:01 PM
Reply to: Message 159 by johnfolton
12-17-2004 7:33 PM


Re: What Craig Said
In the Lake Suigetsu study, only plant and insect materials were dated. Pore fluids or "leachates" would likely be worthless in this case, anyway, unless there were a way to very accurately quantify any sedimentary carbonate input, including the age of any such.
The C-12 carbon dioxide would be more of an acid that would not leave a residual. Likely to decarbonate the leaf one would have to use some form of acid to remove the carbonates.
Nonsensensical mishmash of words. Calcium carbonate with 14C acts essentially identical to that with 12C. And I'd bet a cold beer that every sample Kitagawa and van der Plicht teased out of those cores was, indeed, pretreated with dilute acid to remove any attached carbonate minerals, precisely because they could have been deposited by moving pore fluids.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 171 of 306 (169707)
12-18-2004 10:37 AM
Reply to: Message 167 by johnfolton
12-18-2004 1:47 AM


Re: What Craig Said
The bathtub deposits that don't immediately disintegrate in, say, 5% hydrochloric acid are probably gypsum, not carbonates. Trust me on this - my living comes largely from removing very similar stuff from oil wells.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 186 of 306 (169823)
12-18-2004 11:47 PM
Reply to: Message 184 by TheLiteralist
12-18-2004 11:22 PM


Re: Lake Suigetsu Questions
I'm pretty sure, TL, that the "radiocarbon age" in the second graph is based on a calculation involving only the half-life of carbon 14 and an assumed-constant carbon-14 level in the atmosphere - the level we really had in 1950, perhaps. This "assumed-constant" thing is known to be untrue: that's the whole reason for the paper and the graph. They set out to calculate true levels in the past, and those levels are closely related to the distance a data point is below the "ideal" line on the second graph.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 189 of 306 (169827)
12-19-2004 12:51 AM


Has your carbon correlations of trees and lake varves been tested by these advance atomic spectrograph machines.
All of the Lake Suigetsu dating was done by accelerator mass spectrometry, which is likely what you're talking about. But 14C won't get to as much as 100,000 years back even with this method - the quantity of 14C just gets too small.
Greenland ice cores have been counted back 130,000 years, by the way. And the Vesuvius ash layer from the eruption that buried Pompeii was found in one of those cores, and the count was seven years off - from 79 AD. 7 years out of about 1900 - figure that percentage error for yourself.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 190 of 306 (169828)
12-19-2004 12:54 AM
Reply to: Message 188 by johnfolton
12-19-2004 12:42 AM


Re: What Craig Said
The point if you believe these varves were all laid down one each year, or over millions of years, shouldn't there be evidence of erosion.
Only if the sediments in question were above water level at some point. If they were continuously lake/sea bottom, there would be nothing to erode them.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 232 of 306 (253539)
10-20-2005 8:45 PM
Reply to: Message 224 by Christian
10-20-2005 5:02 PM


You can read the original paper for free if you register at Science | AAAS - and they spam you not. The citation is H. Kitagawa and J. van der Plicht, Science, 20 February 1998; vol. 279: pp1187-1190. The search engine will take you right to it: get the pdf version to see the graphs at their best. And yeah, some of it presupposes knowledge of the jargon, but it's not terribly loaded with obscure terms.

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Coragyps
Member (Idle past 735 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 233 of 306 (253541)
10-20-2005 8:50 PM


There are also several data sets on tree rings from dead-but-not-completely-rotton trees found in bogs in Finland and Germany (and other places, too) that go back 11,000 years or so. The same methods that have just been mentioned for bristlecone pines were used, but on hundreds of trees - ring patterns from any one time were there in duplicates.

Replies to this message:
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