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Author Topic:   Assumptions involved in scientific dating
DOCJ
Inactive Member


Message 61 of 222 (827232)
01-21-2018 3:46 AM
Reply to: Message 1 by Coyote
08-10-2016 10:50 AM


Questions
What is the formula used to determine the age of materials? And what are the constant variables?
Thanks
DOCJ

This message is a reply to:
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Coyote
Member (Idle past 2096 days)
Posts: 6117
Joined: 01-12-2008


Message 62 of 222 (827239)
01-21-2018 10:40 AM
Reply to: Message 61 by DOCJ
01-21-2018 3:46 AM


Re: Questions
What is the formula used to determine the age of materials? And what are the constant variables?
Different materials are aged using different techniques. For example, radiocarbon dating works with materials containing carbon and has an upper limit of about 50,000 years. For other materials and older samples other dating methods are needed.
RAZD has an excellent thread outlining many of these different methods and the very high correspondence between the different dating methods.
As for the formula, all of my books on radiocarbon dating are at the office. The basic method is to detect the levels of C14, which decays at a known rate. That figure, "percent modern" can then be equated to calendar years. Corrections are necessary for isotopic fractionation and calibration is needed to adjust for atmospheric variation.
A lot of details are spread throughout this thread, so take a few minutes to scan previous posts.
Hope this helps.

Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.
Belief gets in the way of learning--Robert A. Heinlein
In the name of diversity, college student demands to be kept in ignorance of the culture that made diversity a value--StultisTheFool
It's not what we don't know that hurts, it's what we know that ain't so--Will Rogers
If I am entitled to something, someone else is obliged to pay--Jerry Pournelle
If a religion's teachings are true, then it should have nothing to fear from science...--dwise1
"Multiculturalism" demands that the US be tolerant of everything except its own past, culture, traditions, and identity.
Liberals claim to want to give a hearing to other views, but then are shocked and offended to discover that there are other points of view--William F. Buckley Jr.

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RAZD
Member (Idle past 1395 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 63 of 222 (827240)
01-21-2018 10:41 AM
Reply to: Message 61 by DOCJ
01-21-2018 3:46 AM


Re: Questions
What is the formula used to determine the age of materials? ...
I'll presume you mean the formula to determine the 14-C age of organic materials.
quote:
Age Calculations
Conventional radiocarbon ages (BP)
A radiocarbon measurement, termed a conventional radiocarbon age (or CRA) is obtained using a set of parameters outlined by Stuiver and Polach (1977), in the journal Radiocarbon. A time-independent level of C14 activity for the past is assumed in the measurement of a CRA. The activity of this hypothetical level of C14 activity is equal to the activity of the absolute international radiocarbon standard.
The Conventional Radiocarbon Age BP is calculated using the radiocarbon decay equation:
t=-8033 ln(Asn/Aon)
Where -8033 represents the mean lifetime of 14C (Stuiver and Polach, 1977). Aon is the activity in counts per minute of the modern standard, Asn is the equivalent cpm for the sample. 'ln' represents the natural logarithm.
A CRA embraces the following recommended conventions:
  • a half-life of 5568 years;
  • the use of Oxalic acid I or II, or appropriate secondary radiocarbon standards (e.g. ANU sucrose) as the modern radiocarbon standard;
  • correction for sample isotopic fractionation (deltaC13) to a normalized or base value of -25.0 per mille relative to the ratio of C12/C13 in the carbonate standard VPDB (more on fractionation and deltaC13);
  • the use of 1950 AD as 0 BP, ie all C14 ages head back in time from 1950;
  • the assumption that all C14 reservoirs have remained constant through time.
Three further terms are sometimes given with reported radiocarbon dates. d14C, D14C and deltaC13.
All are expressed in per mille notation rather than per cent notation (%).
d14C represents the per mille depletion in sample carbon 14 prior to isotopic fractionation correction and is measured by:
d14C=((Asn/Aon) - 1)1000 per mille
D14C represents the 'normalized' value of d14C. 'Normalized' means that the activity is scaled in relation to fractionation of the sample, or its deltaC13 value. All D14C values are normalized to the base value of -25.0 per mille with respect to the standard carbonate (VPDB). D14C is calculated using:
D14C=d14C - 2(dC13 + 25)(1 + d14C/1000) per mille
This value can then be used to calculate the CRA using the equation given above.
Radiocarbon age=-8033 ln(1 + D14C/1000)

Now I will note that 5568 is not that accurate for the half-life of 14-C: the current value is listed as 5,730 40 years (wiki), so a more accurate age would be older than this CRA, however the CRA needs to be corrected anyway due to the variation in 14-C content in the atmosphere from year to year, because it is not constant as assumed.
As Coyote noted in Message 1 this correction is done by comparison to CRA values for samples of known age -- tree rings, lake and marine varves, etc. and this calibration also incorporates the correction for the half life.
This correction in detailed in 14C Calibration and Correlations and the calibration curves for tree rings and varves are
As you can easily see the actual calibrated ages are consistently older than the straight line CRA age.
Enjoy

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Coyote
Member (Idle past 2096 days)
Posts: 6117
Joined: 01-12-2008


(1)
Message 64 of 222 (827241)
01-21-2018 10:45 AM
Reply to: Message 63 by RAZD
01-21-2018 10:41 AM


Re: Questions
Thank, RAZD, for filling in those details.

Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.
Belief gets in the way of learning--Robert A. Heinlein
In the name of diversity, college student demands to be kept in ignorance of the culture that made diversity a value--StultisTheFool
It's not what we don't know that hurts, it's what we know that ain't so--Will Rogers
If I am entitled to something, someone else is obliged to pay--Jerry Pournelle
If a religion's teachings are true, then it should have nothing to fear from science...--dwise1
"Multiculturalism" demands that the US be tolerant of everything except its own past, culture, traditions, and identity.
Liberals claim to want to give a hearing to other views, but then are shocked and offended to discover that there are other points of view--William F. Buckley Jr.

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Percy
Member
Posts: 22359
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.7


(2)
Message 65 of 222 (827243)
01-21-2018 11:28 AM
Reply to: Message 61 by DOCJ
01-21-2018 3:46 AM


Re: Questions
DOCJ writes:
What is the formula used to determine the age of materials? And what are the constant variables?
It would be a good idea to check out the reference Coyote provides first: Answers to Creationist Attacks on Carbon-14 Dating.
While the general concepts are simple, the specifics of the calculation have some details that require some explanation. I'll just quote from the Wikipedia article on Radiocarbon Datin:
quote:
The results from AMS testing are in the form of ratios of 12C, 13C, and 14C, which are used to calculate Fm, the "fraction modern". This is defined as the ratio between the 14C/12C ratio in the sample and the 14C/12C ratio in modern carbon, which is in turn defined as the 14C/12C ratio that would have been measured in 1950 had there been no fossil fuel effect.
Both beta counting and AMS results have to be corrected for fractionation. This is necessary because different materials of the same age, which because of fractionation have naturally different 14C/12C ratios, will appear to be of different ages because the 14C/12C ratio is taken as the indicator of age. To avoid this, all radiocarbon measurements are converted to the measurement that would have been seen had the sample been made of wood, which has a known δ13C value of −25.
Once the corrected 14C/12C ratio is known, a "radiocarbon age" is calculated using:
Age = -8033 · ln(Fm)
The calculation uses Libby's half-life of 5,568 years, not the more accurate modern value of 5,730 years. Libby’s value for the half-life is used to maintain consistency with early radiocarbon testing results; calibration curves include a correction for this, so the accuracy of final reported calendar ages is assured.
AbE: This seems to duplicate RAZD's information in Message 63. I actually typed up this message a few hours ago but didn't have a chance to proof it before I left, so when I returned I just proofed it and posted it, and only then did I notice RAZD's post.
--Percy
Edited by Percy, : AbE.

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DOCJ
Inactive Member


Message 66 of 222 (827272)
01-21-2018 8:36 PM
Reply to: Message 65 by Percy
01-21-2018 11:28 AM


Re: Questions
What assumptions are geologists making when dating rocks, etc? I'm wanting to find out the issues. It's just a matter of if one of you are going to provide them. I'm looking at the information and a few of the assumptions I'm seeing are how much daughter product was in the sample, how much parent was in the sample, that their model of gravitational physics is true, and I'm sure there are some inside the formula such as constant variables..
Thanks for all the information.
Edited by DOCJ, : 😊

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edge
Member (Idle past 1696 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(1)
Message 67 of 222 (827276)
01-21-2018 10:25 PM
Reply to: Message 66 by DOCJ
01-21-2018 8:36 PM


Re: Questions
What assumptions are geologists making when dating rocks, etc?
It's really pretty simple. The assumptions are the the system is closed, the original isotopic composition can be estimated, the decay rates have been very nearly constant, that we can accurately measure the isotopes and that we can do the math correctly.
I assume here that you are talking about radiometric dating.
I'm wanting to find out the issues.
I'm sure you are. This is the typical YEC procedure: find some feature that is not satisfactory to their absolutist approach and attack that point. In other words, they want absolute proof of constant decay rates or absolute certainty of original daughter elements even though most geochronologists are pretty much comfortable with the assumptions. Any doubt, no matter how unrelated, insignificant or mitigated, is precious to them. There are a number of tests for the reasonableness of the assumptions, but the typical forum YEC will simply ignore that fact.
It's just a matter of if one of you are going to provide them. I'm looking at the information and a few of the assumptions I'm seeing are how much daughter product was in the sample, how much parent was in the sample, that their model of gravitational physics is true, and I'm sure there are some inside the formula such as constant variables..
Well for one, I'm not sure what a 'constant variable' is.
A really great thing would be for you, in good faith, to tell us the issues with your own method of dating geological events and then we could have a real discussion about the relative merits.
Edited by edge, : No reason given.

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LamarkNewAge
Member (Idle past 728 days)
Posts: 2236
Joined: 12-22-2015


Message 68 of 222 (827278)
01-21-2018 10:56 PM
Reply to: Message 67 by edge
01-21-2018 10:25 PM


Re: Questions
There were some dating problems with Volcanic ash, right?
I was trying to find a link on the issue.
This is one I found
http://www.turkanabasin.org/...bones-and-rocks-of-contention
plus this book covered the issue
quote:
Roger Lewin
2d edition
366 pages | 51 halftones, 9 line drawings | 6 x 9 | 1986, 1997
Bones of Contention is a behind-the-scenes look at the search for human origins. Analyzing how the biases and preconceptions of paleoanthropologists shaped their work, Roger Lewin's detective stories about the discovery of Neanderthal Man, the Taung Child, Lucy, and other major fossils provide insight into this most subjective of scientific endeavors. The new afterword looks at ways in which paleoanthropology, while becoming more scientific
in many ways, remains contentious.
"[An] un-put-downable book."John Gribbon, Times Educational Supplement
"Not just another 'stones and bones' account of human evolution. It is Lewin's thesis, amply demonstrated, that paleoanthropology is the most subjective of sciences because it engages the emotions of virtually everyone; and since the evidence is scrappy, interpretation is everything. . . . A splendid, stirring, and eye-opening account, to be devoured."Kirkus Reviews, starred review
"[Lewin shows] 'how very unscientific the process of scientific inquiry can be.'. . . Bones of Contention is . . . serious intellectual history."Edward Dolnick, Wall Street Journal
"[Lewin] documents his thesis in persuasive detail. . . . The reader is carried along by the power of Mr. Lewin's reporting."Robert Wright, New York Times Book Review
Close
Contents
.
Acknowledgments
1. Bones of Contention
2. The Storytellers
3. The Taung Child: Rejection
4. The Taung Child: Acceptance
5. Rama's Ape: Resurrected
6. Rama's Ape: Destroyed
7. The Leakeys: Father
8. The Leakeys: Son
9. The KBS Tuff Controversy: Genesis
10. The KBS Tuff Controversy: Denouement
11. Lucy: The Naming
12. Lucy: The Response
13. Man's Place in Nature
Afterword
Notes
Index
Anthropology: Physical Anthropology
Archaeology
Biological Sciences: Natural History | Paleobiology, Geology, and Paleontology
Earth Sciences: Paleontology
History of Science
Bones of Contention: Controversies in the Search for Human Origins, Lewin
Here is a concern that Creationists often raise.
Amazon review snip
quote:
on page 194 (regarding the famous skull 1470): At a conference in Nairobi held in September 1973 they presented 41 separate age determinations on the KBS Tuff [where the skull was found] , WHICH VARIED BETWEEN 223 MILLION AND 0.91 MILLION years of age. What Lewin does NOT tell his readers is that such variation of radiometric dating results are the RULE across ALL of the scientific disciplines which use radiometric dating. The protagonists pick the dates they like and discard the rest of the dates that don’t conform to their pet theories, in this case 40 total other dating results discarded (!) based upon wholly subjective considerations. The trade secret of modern science is that radiometric dating is entirely useless and based on layer upon layer of assumptions.
Amazon.com
Put this keyword into Google
kbs tuff origin of man bones of contention
Any, this is the sort of thing that concerns creationists.
Let questions be asked.
Don't worry so much about the theological motivation.
Just worry about the answers.

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RAZD
Member (Idle past 1395 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 69 of 222 (827291)
01-22-2018 8:58 AM
Reply to: Message 66 by DOCJ
01-21-2018 8:36 PM


Re: Questions
What assumptions are geologists making when dating rocks, etc? I'm wanting to find out the issues. It's just a matter of if one of you are going to provide them. I'm looking at the information and a few of the assumptions I'm seeing are how much daughter product was in the sample, how much parent was in the sample, that their model of gravitational physics is true, and I'm sure there are some inside the formula such as constant variables..
This is getting a bit off-topic for this thread, but there are two basic methodologies for dating rocks.
The first (and oldest known) is relative dating of layers by the law of superposition (wiki):
quote:
The law of superposition is an axiom that forms one of the bases of the sciences of geology, archaeology, and other fields dealing with geological stratigraphy. In its plainest form, it states that in undeformed stratigraphic sequences, the oldest strata will be at the bottom of the sequence. This is important to stratigraphic dating, which assumes that the law of superposition holds true and that an object cannot be older than the materials of which it is composed. The law was first proposed in the late 17th century by the Danish scientist Nicolas Steno.

This is still useful today, because not all types of rock are datable by radiometric methods: dating a layer above the target rock and one below then provides a window of age for the target rock.
The second methodology is of course radiometric methods, and for this I refer you to an excellent reference:
quote:
Radiometric Dating
A Christian Perspective
First edition 1994; revised version 2002.
Radiometric dating--the process of determining the age of rocks from the decay of their radioactive elements--has been in widespread use for over half a century. There are over forty such techniques, each using a different radioactive element or a different way of measuring them. It has become increasingly clear that these radiometric dating techniques agree with each other and as a whole, present a coherent picture in which the Earth was created a very long time ago. Further evidence comes from the complete agreement between radiometric dates and other dating methods such as counting tree rings or glacier ice core layers. Many Christians have been led to distrust radiometric dating and are completely unaware of the great number of laboratory measurements that have shown these methods to be consistent. Many are also unaware that Bible-believing Christians are among those actively involved in radiometric dating.
This paper describes in relatively simple terms how a number of the dating techniques work, how accurately the half-lives of the radioactive elements and the rock dates themselves are known, and how dates are checked with one another. In the process the paper refutes a number of misconceptions prevalent among Christians today. This paper is available on the web via the American Scientific Affiliation and related sites to promote greater understanding and wisdom on this issue, particularly within the Christian community.
This provides an excellent overview of all types of radiometric dating methods.
Enjoy

we are limited in our ability to understand
by our ability to understand
RebelAmerican☆Zen☯Deist
... to learn ... to think ... to live ... to laugh ...
to share.


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JonF
Member (Idle past 158 days)
Posts: 6174
Joined: 06-23-2003


(1)
Message 70 of 222 (827317)
01-22-2018 3:57 PM
Reply to: Message 67 by edge
01-21-2018 10:25 PM


Re: Questions
The assumptions are the the system is closed, the original isotopic composition can be estimated, the decay rates have been very nearly constant
I prefer "premises" to "assumptions" since the latter connotes lack of solid foundation.
The system is rarely assumed closed. Isochron methods indicate if the system has been open and fails to produce a date. Ar-Ar and U-Pb (the two by far the most widely used) also indicate if the system has been opened and often produce a valid date anyway.
Isochron methods produce the original isotopic composition and a date as part of the method. In Ar-Ar the original isotopic composition seldom affects the date. In U-Pb (almost always on zircons) the crystallization process readily incorporates Uranium and strongly rejects lead so the original ratio of lead to Uranium is always zero or infinitesimal.
The absolute constancy of the decay rates of relevant isotopes under terrestrial conditions is as well established as the atomic constituents of a water molecule. The processes that govern decay are fundamental to the operation of the Universe, and changes would leave unmistakable traces in an astonishing number of places. We've looked; they aren't there. http://www.talkorigins.org/origins/postmonth/oct01.html, The Talk.Origins Archive Post of the Month: August 2006.

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Taq
Member
Posts: 9944
Joined: 03-06-2009
Member Rating: 4.8


(1)
Message 71 of 222 (827318)
01-22-2018 4:05 PM
Reply to: Message 66 by DOCJ
01-21-2018 8:36 PM


Re: Questions
DOCJ writes:
I'm looking at the information and a few of the assumptions I'm seeing are how much daughter product was in the sample, how much parent was in the sample, that their model of gravitational physics is true, and I'm sure there are some inside the formula such as constant variables..
None of them are assumptions in the truest sense. They are more akin to the assumptions you use with any instrument and measuring technique. Let's use electronic scales as an example. When you are using electronic scales you assume that gravity is the same, the natural laws governing electricity (i.e. Ohm's Law) are the same, and you are also assuming that magical leprechauns are not producing false data. Radiometric dating is the same.
Constant decay rates: In order for decay rates to change you would need to change the fundamental forces of nature, specifically the strong and weak nuclear forces. Since we observe that these forces are the same throughout the universe, as demonstrated by astronomical observations, we can be very confident that these were the same in the past. There are also specific observations of past decay rates such as the decay of isotopes in Supernova 1987a 170,000 light years away (hence 170,000 years ago) where they were able to measure the decay rates of at least one isotope.
Presence of daughter isotope in newly formed rock: You can entirely avoid this problem by using isochron dating which can actually measure the concentration of daughter product in the newly formed rock. For non-isochron methods, this assumption has already been checked in rocks that are from known and historic volcanic eruptions. For example:
"Two extensive studies done more than 25 years ago involved analyzing the isotopic composition of argon in such flows to determine if the source of the argon was atmospheric, as must be assumed in K-Ar dating (Dalrymple 1969, 26 flows; Krummenacher 1970, 19 flows). Both studies detected, in a few of the flows, deviations from atmospheric isotopic composition, most often in the form of excess 40Ar. The majority of flows, however, had no detectable excess 40Ar and thus gave correct ages as expected. Of the handful of flows that did contain excess 40Ar, only a few did so in significant amounts. The 122 BCE flow from Mt Etna, for example, gave an erroneous age of 0.25 0.08 Ma. Note, however, that even an error of 0.25 Ma would be insignificant in a 20 Ma flow with equivalent potassium content. Austin (1996) has documented excess 40Ar in the 1986 dacite flow from Mount St Helens, but the amounts are insufficient to produce significant errors in all but the youngest rocks."
Radiometric Dating Does Work! | National Center for Science Education
At worst, there is enough atmospheric 40Ar in newly formed igneous rock to cause a difference of just 0.25 million years.
The real strength of radiometric dating is that there are several independent isotope systems that can be used to cross check each other. For example, you can use K/Ar, U/Pb, and Rb/Sr. If radiometric dating didn't work then there would be no reason to predict that these three completely independent isotope systems would produce the same dates, yet they do:
"There are several important things to note about these results. First, the Cretaceous and Tertiary periods were defined by geologists in the early 1800s. The boundary between these periods (the K-T boundary) is marked by an abrupt change in fossils found in sedimentary rocks worldwide. Its exact location in the stratigraphic column at any locality has nothing to do with radiometric dating it is located by careful study of the fossils and the rocks that contain them, and nothing more. Second, the radiometric age measurements, 187 of them, were made on 3 different minerals and on glass by 3 distinctly different dating methods (K-Ar and 40Ar/39Ar are technical variations that use the same parent-daughter decay scheme), each involving different elements with different half-lives. Furthermore, the dating was done in 6 different laboratories and the materials were collected from 5 different locations in the Western Hemisphere. And yet the results are the same within analytical error. If radiometric dating didn’t work then such beautifully consistent results would not be possible."
Radiometric Dating Does Work! | National Center for Science Education
Here is the table that the quote is describing:
Edited by Taq, : No reason given.

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JonF
Member (Idle past 158 days)
Posts: 6174
Joined: 06-23-2003


Message 72 of 222 (827319)
01-22-2018 4:11 PM
Reply to: Message 68 by LamarkNewAge
01-21-2018 10:56 PM


Re: Questions
Wow, what a load of horses**t! The KBS Tuff story is much more complex than that. Some dates were discarded, all for explicit and objective explanations of why they were incorrect. That's the real standard practice; nobody discards data without stating an objective reason. IIRC the initial range of dates was significantly smaller.
I wrote more at Message 5
Edited by JonF, : No reason given.

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Taq
Member
Posts: 9944
Joined: 03-06-2009
Member Rating: 4.8


Message 73 of 222 (827320)
01-22-2018 4:19 PM
Reply to: Message 72 by JonF
01-22-2018 4:11 PM


Re: Questions
JonF writes:
IIRC the initial range of dates was significantly smaller.
The initial spread in the data was that large. It appears that the first samples contained a mixture of really old material that had eroded and mixed with the new material (lahars?). However, once this problem was identified they started getting a much smaller spread in dates.
"In a study to test the feasibility of dating samples from the tuff, the samples were contaminated with non-juvenile components which could not be separated out, giving ages over 200 million years. It was recommended that new samples be collected from which suitable individual crystals could be separated (Fitch and Miller 1970). These new samples were dated at 2.61 +/- 0.26 million years, based on the 40Ar/39Ar dating method (Fitch and Miller 1970). "
CD031: KBS Tuff dating
Edited by Taq, : No reason given.

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edge
Member (Idle past 1696 days)
Posts: 4696
From: Colorado, USA
Joined: 01-09-2002


(1)
Message 74 of 222 (827329)
01-22-2018 7:45 PM
Reply to: Message 70 by JonF
01-22-2018 3:57 PM


Re: Questions
I prefer "premises" to "assumptions" since the latter connotes lack of solid foundation.
The system is rarely assumed closed. Isochron methods indicate if the system has been open and fails to produce a date. Ar-Ar and U-Pb (the two by far the most widely used) also indicate if the system has been opened and often produce a valid date anyway.
Isochron methods produce the original isotopic composition and a date as part of the method. In Ar-Ar the original isotopic composition seldom affects the date. In U-Pb (almost always on zircons) the crystallization process readily incorporates Uranium and strongly rejects lead so the original ratio of lead to Uranium is always zero or infinitesimal.
Complete agreement. I never know how far to simplify things and use common terminology. Although, I have to say that radiometric dating has changed a lot since I had any of that kind of work done.
One thing that most people do not understand is that if there a problem with a date it's kind of obvious from the viewpoint of an experienced researcher. In fact, right now I'm dealing with data that just looks bad for various reasons. It's going to take some more work. Same thing with the KBS Tuff. It didn't quite fit the known geology. And there is always an explanation.

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 Message 70 by JonF, posted 01-22-2018 3:57 PM JonF has not replied

  
DOCJ
Inactive Member


Message 75 of 222 (827330)
01-22-2018 10:29 PM
Reply to: Message 67 by edge
01-21-2018 10:25 PM


Re: Questions
I'm merely interested in the truth about dating methods. The age debate wouldn't refute my faith because it is adaptable. I generally view conventional science as a out dated way of thinking. I don't think all of the views are accurate in describing the universe. I'm just interested in the truth. In interpreting your response, it does seem as if you do not care about the accuracy of dating. It's as if you are fine with whatever. Which is fine but I'm more interested with the truth. And if you represent the main way of thinking I can definitely see why there is a debate. Christians who are in seek mode are looking to conclude in truth not on bias with regards to dating. If your attitude is a standard within the geology field, it's not a good thing. Every detail should matter, anchoring is unhealthy. FYI: I believe in the electrical model of the universe, birkeland currents, plasma physics, and accept gravitational physics as a weak force. Essentially the birkeland current would develop a universe that changes the composition of material, and the like due to the electrical current that would connect everything in the universe. There is absolutely no way to determine with out a doubt the age of the universe or the earth with conventional methods.
Electricverse
Electric Sun
NoBB
Edited by DOCJ, : Clarification
Edited by DOCJ, : Clarification

This message is a reply to:
 Message 67 by edge, posted 01-21-2018 10:25 PM edge has not replied

Replies to this message:
 Message 76 by Coyote, posted 01-22-2018 10:52 PM DOCJ has replied
 Message 77 by Pressie, posted 01-23-2018 3:56 AM DOCJ has not replied
 Message 89 by RAZD, posted 01-23-2018 8:12 AM DOCJ has replied
 Message 96 by Percy, posted 01-23-2018 9:56 AM DOCJ has not replied
 Message 102 by Taq, posted 01-23-2018 11:09 AM DOCJ has replied

  
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