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  Topic: AF Dave's UPDATED Creator God Hypothesis, Creation/Evolution Debate< Next Oldest | Next Newest >  
jeannot



Posts: 1201
Joined: Jan. 2006

(Permalink) Posted: Sep. 16 2006,12:49   

Quote (Arden Chatfield @ Sep. 16 2006,12:29)
Quote (Stephen Elliott @ Sep. 16 2006,12:23)
Quote (ericmurphy @ Sep. 16 2006,10:35)
You assume your flood carved the Grand Canyon, despite the fact that you have no evidence your flood ever even happened, and even if you did, you have no way of knowing if the Grand Canyon happened before the flood, during, or after the flood, because you have no independent method of dating it. Was every canyon everywhere carved during the "flood"?

Sorry if this sounds obtuse but how could a Global flood create a canyon? Any canyon. If the whole World was under water, how would it move in a way to carve rock like that?

Open to anyone.

I've wondered that for years.

I think it reflects a Creationist thought process "Lots of Water Do Big Thing,  Make Canyons". I don't think they think it through further than that.

Our friend Dave referred to underground sources of water, therefore unable to erode lanscapes. But presumably, there was enough rain for the erosion of the Grand Canyon in 40 days, but not too much so that Noah could build his arch safely.

You get the picture?

  
ericmurphy



Posts: 2460
Joined: Oct. 2005

(Permalink) Posted: Sep. 16 2006,13:04   

Quote (jeannot @ Sep. 16 2006,17:49)
Our friend Dave referred to underground sources of water, therefore unable to erode lanscapes. But presumably, there was enough rain for the erosion of the Grand Canyon in 40 days, but not too much so that Noah could build his arch safely.

You get the picture?

Except for the fact that Dave's "flood" doesn't have any water to begin with. That's the principal problem with his flood "hypothesis." The rest is just details.

But without a source (or a sink) for his flood, he's up a dry creek without a bicycle. His canoe ain't gonna do him any good at all.

--------------
2006 MVD award for most dogged defense of scientific sanity

"Atheism is a religion the same way NOT collecting stamps is a hobby." —Scott Adams

  
deadman_932



Posts: 3094
Joined: May 2006

(Permalink) Posted: Sep. 16 2006,13:29   

Quote
So to those of us in the U.S. - let's resolve to devote at least as much time, energy and resources to the upcoming election as to diversions like Davey-doodles.

I certainly plan to. After all, the truth of the matter is that creationism and "ID" represent religio-political power moves, anyway. It ain't about science, that's for sure.
Quote
I visited the Grand Canyon aprox 10 years ago. Started just north of Flagstaff and drove along towards Kingsman then crossed the Hoover dam.

I was born in the southwest (New Mexico) and being at the Grand Canyon in winter is a highlight of my life. The National Parks of Utah in winter aren't too shabby, either -- I'd just make sure I buy my beverages of choice out-of-state -- I found it's just easier.

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AtBC Award for Thoroughness in the Face of Creationism

  
BWE



Posts: 1902
Joined: Jan. 2006

(Permalink) Posted: Sep. 16 2006,13:49   

Quote (Russell @ Sep. 16 2006,16:46)
Wow. 193 pages of this crap! Truly impressive. Kudos to all with the perseverance to keep holding afd's feet to the fire. But beyond a certain point, incinerated feet can't get any more incinerated.

Seriously. It occurs to me that the only reason sane people take the time to even confront this pre-medieval silliness is because of the scary political prominence of the would-be theocrats. So to those of us in the U.S. - let's resolve to devote at least as much time, energy and resources to the upcoming election as to diversions like Davey-doodles.

The other fundies run away after a few pages or get into subjective qualities when everyone goes bonkers. This one stays around and offers a very detailed look into a particular mindset.

I for one truly enjoy the often bizzare banter that develops when the difficult student (Dave) pops up with some Chickian response to the science teacher and all the good students have to say "No,no, no. You're gettin it wrong."

But the difficult student sticks to his (fluid ) ideas and the class moves on. I can't wait to get to various core samples personally. I learned a bit about various Rm techniques and now I'm off to another topic.

Hopefully, we can squeeze in a discussion of the founding fathers if we get lucky. I offered Dave to discuss his book on Dave's blog (I even bought the wretched thing) but he petered out there. I would love to have a one on one debate with him on the idea that the founding fathers wanted a christian nation but, since I appear to be sidelined by Dave at the moment, I will have to be content with a quick comment now and then.
:)

--------------
Who said that ev'ry wish would be heard and answered
When wished on the morning star
Somebody thought of that, and someone believed it
Look what it's done so far

The Daily Wingnut

   
Ichthyic



Posts: 3325
Joined: May 2006

(Permalink) Posted: Sep. 16 2006,13:52   

Quote
one guy with a limited amount of bandwidth


THAT'S what we keep telling you Dave!

very limited, indeed.

one might even say straw-like.

--------------
"And the sea will grant each man new hope..."

-CC

  
afdave



Posts: 1621
Joined: April 2006

(Permalink) Posted: Sep. 17 2006,01:05   



JonF...
Quote
So they contain different amounts of parent and daughter. But in an isotopically homogeneous source the ratio of isotopes of the same element is constant throughout the relevant volume, and at solidification all minerals that solidify from that source contain the same ratio of isotopes of the same element as the parent melt did.  That's the extra information that allows us to get the original amount of daughter at solidification, because the amount of the non-radiogenic isotope of the daughter in the samples doesn't change over time.
OK. So let's say our hypothetical example in the chart above are from the same lava flow so Tracy will be happy. (Oh, and Tracy, the plots are not "goofy" ... they do plot isochron ratios.  As I explained, the ratios are not shown for simplicity.)  So we select 6 samples and do a Whole Rock Isochron analysis.  Let's also assume that we are doing a Rb/Sr analysis, so in this example, the non-radiogenic daughter product that JonF refers to would be 86Sr.  The radiogenic parent would be 87Rb and the radiogenic daughter would be 87Sr.  This means that the "daughter units of abundance" (vertical axis) is really the ratio 87Sr/86Sr (now are you happy, Tracy?).  And the "parent units of abundance (horizontal axis) is really the ratio 87Rb/86Sr.  

So here is our data again from the lab (I just eyeballed the charts) ...

Sample 1:  P=1.1, D=1.8
Sample 2:  P=1.7, D=2.3
Sample 3:  P=2.1, D=2.35
Sample 4:  P=2.2, D=2.8
Sample 5:  P=2.8, D=3.2
Sample 6:  P=3.3, D=3.6

Where P stands for Parent ratio, D stands for Daughter ratio ... so what we are saying for this example is for Sample 1, the Parent ratio, P = 87Rb/86Sr = 275 (nm/g) / 250 (nm/g) = 1.1 and the Daughter ratio, D = 87Sr/86Sr = 450 (nm/g) / 250 (nm/g) = 1.8.  These are typical values that you might find.  The units nm/g mean nano-moles per gram.

Now that we have some real numbers attached to our hypothetical charts, let's return to the assumptions.

"DEEP TIMER" ASSUMPTION:  The Daughter Ratio, D, was the same in all six samples when the sample was formed.  In this case, the samples were formed at the same time from the same lava flow, so they are "cogenetic."  This means that we are assuming a Daughter ratio, D = 1.0 for all six samples.  So Sample 1 might have a ratio of 250 / 250, Sample 2 might be 150 / 150 etc.  So the actual concentration (nm/g) might be different among the different samples, but the assumption is merely saying that the ratio of concentrations of Radiogenic Daughter to Stable Daughter is the same among all the samples when the sample is first formed.

Now I understand Jon's statement that "in an isotopically homogeneous source the ratio of isotopes of the same element is constant throughout the relevant volume, and at solidification all minerals that solidify from that source contain the same ratio of isotopes of the same element as the parent melt did", but I guess I'm just not seeing how you can say that [i]this was definitely an isotopically homogeneous source."  I understand that it was "cogenetic" ... no problem with that.  But how can we say that the 87Sr/86Sr ratio was the same for all samples when formed?  Why should there be ANY 87Sr at all when formed?  Or if there is some, why couldn't there be a lot so that the ratio is 1.5 or 2.0 initially?  I mean ... the parent ratio, 87Rb/86Sr sure isn't the same for all the samples.  Why should the daughter ratio be the same?  Are you telling me that if I go buy a furnace and melt some rock and then let it cool, that my 87Sr/86Sr ratio will be the same for any sample, but my 87Rb/86Sr ratio will NOT be the same?  What mechanism could possibly be operating on the initial 87Rb that would not also be operating on the initial 87Sr to distribute it variously and thus yield different ratios for BOTH parent and daughter ratios?

******************************************************

Stephen Elliot...
Quote
Sorry if this sounds obtuse but how could a Global flood create a canyon? Any canyon. If the whole World was under water, how would it move in a way to carve rock like that?

Open to anyone.


The Missoula Flood story is one worth reading and gives a very good explanation of how the Grand Canyon and many others were formed ... you should read the whole story here ...

http://www.answersingenesis.org/docs2003/1209missoula.asp

Better yet ... spend some time at the AIG web site and buy some of their books.  But don't let these guys know if you do ... they will laugh you off the planet!

Quote
The flood overtopped a ridge north of the Snake River, rapidly cutting a narrow canyon 500 feet deep.  The modern Palouse River that used to flow west into the Columbia River before the flood now takes a 90 degree left-hand turn south and flows through the canyon carved by the flood.  This is called a water gap in which a river or stream flows through a barrier instead of flowing around it.  If a geologist did not know about the Lake Missoula Flood, he would have suggested one of three main speculations on the formation of water gaps.  But it was formed in the Lake Missoula flood.  The Lake Missoula flood provides an analog for the thousand or more rivers over the earth that now flow through mountain barriers, sometimes through gaps much deeper than Grand Canyon.  The river should have gone around the barrier, if the slow processes over millions of years model were true, but these water gaps through transverse barriers can be cut rapidly during the Genesis Flood.6


--------------
A DILEMMA FOR THE COMMITTED NATURALIST
A Hi-tech alien spaceship lands on earth ... DESIGNED.
A Hi-tech alien rotary motor found in a cell ... NOT DESIGNED.
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Stephen Elliott



Posts: 1776
Joined: Oct. 2005

(Permalink) Posted: Sep. 17 2006,02:12   

Quote (afdave @ Sep. 17 2006,06:05)
Stephen Elliot...  
Quote
Sorry if this sounds obtuse but how could a Global flood create a canyon? Any canyon. If the whole World was under water, how would it move in a way to carve rock like that?

Open to anyone.


The Missoula Flood story is one worth reading and gives a very good explanation of how the Grand Canyon and many others were formed ... you should read the whole story here ...

http://www.answersingenesis.org/docs2003/1209missoula.asp

Better yet ... spend some time at the AIG web site and buy some of their books.  But don't let these guys know if you do ... they will laugh you off the planet!

 
Quote
The flood overtopped a ridge north of the Snake River, rapidly cutting a narrow canyon 500 feet deep.  The modern Palouse River that used to flow west into the Columbia River before the flood now takes a 90 degree left-hand turn south and flows through the canyon carved by the flood.  This is called a water gap in which a river or stream flows through a barrier instead of flowing around it.  If a geologist did not know about the Lake Missoula Flood, he would have suggested one of three main speculations on the formation of water gaps.  But it was formed in the Lake Missoula flood.  The Lake Missoula flood provides an analog for the thousand or more rivers over the earth that now flow through mountain barriers, sometimes through gaps much deeper than Grand Canyon.  The river should have gone around the barrier, if the slow processes over millions of years model were true, but these water gaps through transverse barriers can be cut rapidly during the Genesis Flood.6

During the flood there would be no rivers or dry land though. Wasn't everything covered by water? Surely water action would tend to smooth rock formations during a global flood, not cut canyons.

So what is next? The canyon was cut after the flood receded by trapped flood water?

If you are going to use that argument then where did all the other water go when it left the land? Was the remnant water just forgotten about by God? Did he leave it there on purpose to cut canyons?

Or maybe the flood story in the Bible is not 100% correct. Could it not be an analogy, a legend or a means to just scare peope to do what the priesthood tells them?

  
JonF



Posts: 634
Joined: Feb. 2005

(Permalink) Posted: Sep. 17 2006,03:12   

Quote (Tracy P. Hamilton @ Sep. 16 2006,16:51)
The plots are goofy.  Isochron plots plot isotope ratios.

Yup.  Wonder where he got 'em.  There are lots of good illustrative plots on the Web, our Davie managed to dig up a lousy and misleading set.
Quote
Doing multiple whole-rock isochrons can be used to derive the age of source material instead of solidification of the igneous rock.

Davie-doo doesn't even know the uints of the axes, he doesn't have a prayer of understanding how that works.
Quote
Particularly instructive would be isochrons from individual minerals within the same sample.

Do you mean a mineral isochron, in which each sample is an individual mineral, or something else?  Davie did mention mineral isochrons, but he seems to think that theer's a mineral isochron method and a whole-rock isochron method, while in reality there's an isochron method that is applied to different types of samples.  But that's nothing compared to his other misunderstandings.
Quote
Proximity is not enough to guarantee cogenetic origin.. Are these the same lava flow, or not?

Are you thinking Austin?  I considered the possibility. Davie-diddles stated that they are hypothetical samples.  He may be lying.

  
JonF



Posts: 634
Joined: Feb. 2005

(Permalink) Posted: Sep. 17 2006,04:07   

{Sigh}  You really need to learn about this stuff, Davie, you can't just make it up as you go along.  Oh, and how 'bout them Grand Staircase paleosols?  Waiting for your explanation, especially what possible mechanism held the plants in place with their roots in growing position and packed sediment around them.  Gee, isn't that kind of like your "what possible mechanism" question below?  Of course, there's an answer for your question, but no answer for mine!
 
Quote (afdave @ Sep. 17 2006,07:05)
I guess I'm just not seeing how you can say that this was definitely an isotopically homogeneous source."  I understand that it was "cogenetic" ... no problem with that.  But how can we say that the 87Sr/86Sr ratio was the same for all samples when formed?

That's pretty much the definition of cogenetic; isotopically homogeneous. We know that there's a very very very good chance that the ratio was the same for all samples because the data plots on a straight line today. (The example you picked doesn't plot on a good-enough straight line, but that's a minor point).  Straight lines can be caused by identical initial ratios, mixing in sources with different isotopic ratios (but we have very good evidence that such lines are rare) or random chance (but that's not going to happen often).  It's faintly possible that a very few of the tens of thousands of isochron dates are in error because of mixing or random chance; it's not possible that they are all in error, or even that a lot of our dates are in error.
 
Quote
Why should there be ANY 87Sr at all when formed?

It's everywhere, Davie-doodles.  About 0.0005% of you is strontium, and the isotopic ratio in you is at least close to today's average world-wide isotopic ratio.  (And about 0.001% of you is Rb).
 
Quote
Or if there is some, why couldn't there be a lot so that the ratio is 1.5 or 2.0 initially?

You are confusing [i]quantities with ratios.  Having a lot means nothing about the isotopic ratio.

The initial ratio is wherever the Y-intercept is; either whoever made up the samples you chose either arbitrarily decided to make the Y-intercept 1 or they normalized the initial ratio to 1.  In reality, there's an average 87Sr/86Sr concentration over the entire Earth (actually, there's a mantle average and a slightly different crustal average).  Of course, this overall average changes over time as 87Rb decays to 87Sr.  In most cases, the Y-intercept of an isochron turns out to be very close to the overall average concentration at the time indicated by the slope of the isochron ... samples that we measure as younger tend to have a higher initial 87Sr/86Sr concentration ... how do you like them kumquats!  E.g. real initial 87Sr/86Sr concentrations (as measured by the Y-intercept of the isochron) run in the vicinity of 0.70, real initial 143Nd/144Nd ratios run in the vicinity of 0.51, both for rocks measured as a few billion years old.  Any theory of the meaning of isochrons has to explain this fact ... you won't forget that as the discussion continues, will you, Davie-diddles?
 
Quote
I mean ... the parent ratio, 87Rb/86Sr sure isn't the same for all the samples.  Why should the daughter ratio be the same?  Are you telling me that if I go buy a furnace and melt some rock and then let it cool, that my 87Sr/86Sr ratio will be the same for any sample, but my 87Rb/86Sr ratio will NOT be the same?  What mechanism could possibly be operating on the initial 87Rb that would not also be operating on the initial 87Sr to distribute it variously and thus yield different ratios for BOTH parent and daughter ratios?

Your ignorance is showing again, Dave.  You really should read the links I gave, you need to learn a lot more before you're ready to discuss.

You bet your bippy that, if you go buy a furnace and melt some rock and then let it cool, your 87Sr/86Sr ratio will be the same for any sample and your 87Rb/86Sr ratio will NOT be the same between samples.  Absolutely guaranteed.

The "possible mechanism" is basic chemistry and statistics.  87Sr and 86Sr atoms are chemically identical and near-as-dammit mechanically identical; they're the same size (insofar as the size of an atom has any meaning) and almost the same mass (it takes some serious and large and high-tech equipment to separate them based on mass).  So, when a crystal is forming from an isotopically homogeneous melt and for one reason or another a strontium atom gets incorporated in the crystal, the probability that the atom is an 86Sr atom is the same as the ratio of 86Sr atoms to all Sr atoms in the melt and so on for all the four isotopes.  And, since we are working with untold megazillions of atoms in even small samples, the law of large numbers takes over. This immediately leads to two facts: the ratio of any two strontium isotopes in the solidified crystal is the same as it was in the melt, and the ratio of any two strontium isotopes in the melt does not change as crystals solidify from it (although the amount of strontium in the melt can and does change).

But Rb atoms are chemically and mechanically very different from Sr atoms.  Rb has one electron in its outer shell, Sr has two.  Rb+ is 1.48 Angstroms "diameter", Sr++ is 1.13 Angstroms "diameter".  So Rb doesn't get incorporated where Sr gets incorporated, and there's no probability that connects the Rb isotopic uptake with the Sr isotopic concentrations.  Of course, the initial proportion of 87Rb to 85Rb in the crystal will be the same as it was in the melt, and for the same reasons as for strontium, but that's not relevant to dating.
 
Quote
The Missoula Flood story is one worth reading and gives a very good explanation of how the Grand Canyon and many others were formed

The features formed by the Missoula flood bear no resemblance to the Grand Canyon features.

  
Occam's Aftershave



Posts: 5287
Joined: Feb. 2006

(Permalink) Posted: Sep. 17 2006,05:51   

Quote
AFDave: The Missoula Flood story is one worth reading and gives a very good explanation of how the Grand Canyon and many others were formed


Tell me again Dave, how did that buried canyon in China form?  You know, the one I showed you that's cut into rock hard limestone and covered with over 17,000 feet of sediment?

--------------
"CO2 can't re-emit any trapped heat unless all the molecules point the right way"
"All the evidence supports Creation baraminology"
"If it required a mind, planning and design, it isn't materialistic."
"Jews and Christians are Muslims."

- Joke "Sharon" Gallien, world's dumbest YEC.

  
ericmurphy



Posts: 2460
Joined: Oct. 2005

(Permalink) Posted: Sep. 17 2006,06:06   

Quote (afdave @ Sep. 17 2006,06:05)
The Missoula Flood story is one worth reading and gives a very good explanation of how the Grand Canyon and many others were formed ... you should read the whole story here ...

Amazing, isn't it, how even after it's pointed out to Dave that the Missoula river canyon looks nothing like the Grand Canyon and was formed via totally different mechanisms, he still points to it as an example of how the Grand Canyon was formed.

It really makes you wonder if Dave is any more educable than a dog.

One more time, Dave: How do you know how old the Grand Canyon is, without reference to your Bible? After all, the Bible certainly is not an eyewitness (or even a god-witness) account of the formation of the Grand Canyon; it doesn't even mention the Grand Canyon. Leaving aside for the moment the fact that your "flood" didn't happen, how would you know whether the Grand Canyon was formed before, during, or after the "flood'?

You wouldn't, would you?

--------------
2006 MVD award for most dogged defense of scientific sanity

"Atheism is a religion the same way NOT collecting stamps is a hobby." —Scott Adams

  
Tracy P. Hamilton



Posts: 1239
Joined: May 2006

(Permalink) Posted: Sep. 17 2006,06:45   

Quote (JonF @ Sep. 17 2006,08:12)

 
Quote (Tracy P. Hamilton @ Sep. 16 2006,16:51)
The plots are goofy.  Isochron plots plot isotope ratios.

Yup.  Wonder where he got 'em.  There are lots of good illustrative plots on the Web, our Davie managed to dig up a lousy and misleading set.
   
Quote
Doing multiple whole-rock isochrons can be used to derive the age of source material instead of solidification of the igneous rock.

Davie-doo doesn't even know the uints of the axes, he doesn't have a prayer of understanding how that works.
   
Quote
Particularly instructive would be isochrons from individual minerals within the same sample.

Do you mean a mineral isochron, in which each sample is an individual mineral,



Yes.
Quote (JonF @ Sep. 17 2006,08:12)

Davie did mention mineral isochrons, but he seems to think that theer's a mineral isochron method and a whole-rock isochron method, while in reality there's an isochron method that is applied to different types of samples.  But that's nothing compared to his other misunderstandings.
   
Quote
Proximity is not enough to guarantee cogenetic origin.. Are these the same lava flow, or not?

Are you thinking Austin?  I considered the possibility. Davie-diddles stated that they are hypothetical samples.  He may be lying.


I suspect the plots are from the "RATE" book.  Just a guess.

--------------
"Following what I just wrote about fitness, you’re taking refuge in what we see in the world."  PaV

"The simple equation F = MA leads to the concept of four-dimensional space." GilDodgen

"We have no brain, I don't, for thinking." Robert Byers

  
Tracy P. Hamilton



Posts: 1239
Joined: May 2006

(Permalink) Posted: Sep. 17 2006,08:04   

Quote (afdave @ Sep. 17 2006,06:05)



JonF...    
Quote
So they contain different amounts of parent and daughter. But in an isotopically homogeneous source the ratio of isotopes of the same element is constant throughout the relevant volume, and at solidification all minerals that solidify from that source contain the same ratio of isotopes of the same element as the parent melt did.  That's the extra information that allows us to get the original amount of daughter at solidification, because the amount of the non-radiogenic isotope of the daughter in the samples doesn't change over time.
OK. So let's say our hypothetical example in the chart above are from the same lava flow so Tracy will be happy.


Then there should be only one point, not a line!

Quote (afdave @ Sep. 17 2006,06:05)

(Oh, and Tracy, the plots are not "goofy" ... they do plot isochron ratios.  As I explained, the ratios are not shown for simplicity.)  So we select 6 samples and do a Whole Rock Isochron analysis.  Let's also assume that we are doing a Rb/Sr analysis, so in this example, the non-radiogenic daughter product that JonF refers to would be 86Sr.  The radiogenic parent would be 87Rb and the radiogenic daughter would be 87Sr.  This means that the "daughter units of abundance" (vertical axis) is really the ratio 87Sr/86Sr (now are you happy, Tracy?).  And the "parent units of abundance (horizontal axis) is really the ratio 87Rb/86Sr.  

So here is our data again from the lab (I just eyeballed the charts) ...

Sample 1:  P=1.1, D=1.8
Sample 2:  P=1.7, D=2.3
Sample 3:  P=2.1, D=2.35
Sample 4:  P=2.2, D=2.8
Sample 5:  P=2.8, D=3.2
Sample 6:  P=3.3, D=3.6



The this would mean that parts of the same lava flow are chemically different.

Do you see the problem yet?

--------------
"Following what I just wrote about fitness, you’re taking refuge in what we see in the world."  PaV

"The simple equation F = MA leads to the concept of four-dimensional space." GilDodgen

"We have no brain, I don't, for thinking." Robert Byers

  
JonF



Posts: 634
Joined: Feb. 2005

(Permalink) Posted: Sep. 17 2006,12:57   

Quote (Tracy P. Hamilton @ Sep. 17 2006,14:04)
 
Quote (afdave @ Sep. 17 2006,06:05)
OK. So let's say our hypothetical example in the chart above are from the same lava flow so Tracy will be happy.

Then there should be only one point, not a line!

Er, maybe, maybe not.  In a message to AfDave I pointed out that samples from different parts of one lava flow commonly have different makeups of minerals, and therefore whole-rock methods can and do give rise to different points on an isochron plot.  E.g. Rb-Sr whole-rock isochron ages of late Precambrian to Cambrian igneous rocks from southern Britain.

==================

Oh, Davie-doodles, while looking for the above reference I stumbled across Age determination of Precambrian rocks from Greenland: past and present.  He's speaking of dating in Greenland, and he doesn't totally support my claims about the history of radiometric dating, but he sure rebuts your claim that K-Ar is the most common method of dating:
 
Quote
The history of geochronology can be roughly divided into three periods:

1) a period of single-sample K-Ar and Rb-Sr mineral or whole-rock age determinations;
2) a time when most ages were determined with the help of Rb-Sr and Pb-Pb whole-rock isochrons and multi-grain zircon U-Pb isotope data;
3) the present, where 'single' zircon U-Pb data are the preferred method to obtain rock ages.
...

The first results of K-Ar and Rb-Sr single-sample dating for Greenland rocks were published around 1960. ...

By the beginning of the 1970s, dating of whole rocks with the help of Rb-Sr isochrons had come into general use. ...

Among the first to report modern U-Pb zircon data for Greenland rocks was Baadsgaard (1973), ...

{emphasis added}

  
Crabby Appleton



Posts: 250
Joined: May 2006

(Permalink) Posted: Sep. 17 2006,21:12   

Quote (afdave @ Sep. 15 2006,11:48)
It also is helpful in dialogue to know where a person is coming from.

Yes, American history to me is about the United States of America, which in my opinion, began with white settlers.  Sorry if that sounds insensitive or something, but that appears to be the facts of history.  And I'm not excusing Indian mistreatment either.  Just stating the facts.

Yes, it is useful to know where a person is coming from. Your condescending attitude towards non whites (and Native Americans in particular) has already been noted. You've also made the claim that your "good book" can explain racial differences. I can't wait for that explanation.

You aren't stating the facts, you are expressing your massively ignorant opinions.

American History extends farther into the past than your "inerrant mythology" can account for so you have to discredit anything that predates your dogma.

We don't even need to discuss pre Clovis sites to blow your 'merican history starts with fundy white immigrants wiping out the local inhabitants view of American History (much less the History of the Universe).

Let's add racist to moron and willfully ignorant liar!

  
Mike PSS



Posts: 428
Joined: Sep. 2006

(Permalink) Posted: Sep. 17 2006,23:58   

zzzzzzzzzzzzzzZZZZZZZZZZZZZZT!!!!!!!!

It's taken a while but AFDave has finally blown my cloaking device.  I invested heavily in time and money to protect my lurker status but all previous protections are now null and void.

As a long time lurker since page 1 of this thread (and the previous related topics in April06) I've laughed (and almost cried) at the antics to prove the present Hypothesis under question.  The latest Isochron set-up by AFDave went over the top for me.

I was reading the initial Isochron post (and JonF and Tracy Hamilton response) and glanced over to my bookshelf full of my undergrad chemical engineering textbooks to see where AFDave had gone wrong (again).  I didn't have to get further than my freshman math texts, not even the vector calc or matrix algebra is needed for this argument.  I guess AFDave's EE degree never went into variance over time (d/dt) or how this relation could be extracted from Isochron evidence to derive the ratios in question.  I can almost predict AFDave's argument without knowing the details of Isochron dating since the math is fairly straight forward BUT can be misrepresented by hand-waving and jargon to those without a graphical interpretation skill in there head (something I'm blessed/cursed with).  

If AFDave wants to misrepresent mathematical arguments as it relates to raw data then he should choose reaction rate chemistry or IR plots of mixed organic compounds.  Those data sets are tough to interpret except by skilled or experienced technicians.

I look forward to the mathematical gymnastics that AFDave will have to display in this topic.  Let the mathematically challenged special olympics begin.

And..... thanks for all the patience and time of all the regular posters on this thread.  It's good reading on plane trips.

Mike PSS

  
MidnightVoice



Posts: 380
Joined: Aug. 2005

(Permalink) Posted: Sep. 18 2006,02:55   

Quote (Mike PSS @ Sep. 18 2006,04:58)
zzzzzzzzzzzzzzZZZZZZZZZZZZZZT!!!!!!!!

It's taken a while but AFDave has finally blown my cloaking device.  I invested heavily in time and money to protect my lurker status but all previous protections are now null and void.

As a long time lurker since page 1 of this thread (and the previous related topics in April06) I've laughed (and almost cried) at the antics to prove the present Hypothesis under question.  The latest Isochron set-up by AFDave went over the top for me.

Welcome!   :D

And I am glad Dear Dave does serve a useful purpose here   :D

--------------
If I fly the coop some time
And take nothing but a grip
With the few good books that really count
It's a necessary trip

I'll be gone with the girl in the gold silk jacket
The girl with the pearl-driller's hands

  
Tracy P. Hamilton



Posts: 1239
Joined: May 2006

(Permalink) Posted: Sep. 18 2006,05:17   

Quote (JonF @ Sep. 17 2006,17:57)

 
Quote (Tracy P. Hamilton @ Sep. 17 2006,14:04)
     
Quote (afdave @ Sep. 17 2006,06:05)
OK. So let's say our hypothetical example in the chart above are from the same lava flow so Tracy will be happy.

Then there should be only one point, not a line!

Er, maybe, maybe not.  In a message to AfDave I pointed out that samples from different parts of one lava flow commonly have different makeups of minerals, and therefore whole-rock methods can and do give rise to different points on an isochron plot.


If the magma was not completely melted.  You have to put it in very simple terms for AFDave.

One wonders if he will acknowledge the clear statement of the history of which method was most popular in radiometric dating.  Maybe AFDave will get Tyred of it.

 :p

--------------
"Following what I just wrote about fitness, you’re taking refuge in what we see in the world."  PaV

"The simple equation F = MA leads to the concept of four-dimensional space." GilDodgen

"We have no brain, I don't, for thinking." Robert Byers

  
The Ghost of Paley



Posts: 1703
Joined: Oct. 2005

(Permalink) Posted: Sep. 18 2006,05:51   

Crabby:

 
Quote
Yes, it is useful to know where a person is coming from. Your condescending attitude towards non whites (and Native Americans in particular) has already been noted. You've also made the claim that your "good book" can explain racial differences. I can't wait for that explanation.


How is he being "condescending", Mr. PC?

--------------
Dey can't 'andle my riddim.

  
Ved



Posts: 398
Joined: Oct. 2005

(Permalink) Posted: Sep. 18 2006,06:40   

Welcome, Mike!
Quote (Mike PSS @ Sep. 18 2006,05:58)
The latest Isochron set-up by AFDave went over the top for me.

Me too. Except that for me it just got too boring. I was able to keep up with and be interested in the likes of the zircon discussion and the xenoliths discussion but this one just catches my brain flat-footed. I could even write this one off in my mind having dave "win" this argument and he'd still be no closer to supporting his "hypothesis".

  
Ved



Posts: 398
Joined: Oct. 2005

(Permalink) Posted: Sep. 18 2006,06:53   

Quote (afdave @ Sep. 16 2006,10:19)
I am happy to take a much closer look at dendro, ice cores, limestone, C14 and many other things in due course ... however, I am only one guy with a limited amount of bandwidth and I have to take one topic at a time.

It seemed logical to me to look closely at radiometric dating since we just finished looking at the Grand Staircase in some detail and it is claimed that the layers of the Grand Staircase can be dated (or at least bracketed) radiometrically.

Is this such an unreasonable approach?

In order to finish looking at radiometric dating, you're going to need to look at dendrochronology and core samples and how they relate to RM dating.

RM doesn't exist in a vacuum.

  
JonF



Posts: 634
Joined: Feb. 2005

(Permalink) Posted: Sep. 18 2006,07:18   

Quote (Tracy P. Hamilton @ Sep. 18 2006,11:17)
 
Quote (JonF @ Sep. 17 2006,17:57)

Er, maybe, maybe not.  In a message to AfDave I pointed out that samples from different parts of one lava flow commonly have different makeups of minerals, and therefore whole-rock methods can and do give rise to different points on an isochron plot.

If the magma was not completely melted.

Not necessarily.  Since solidification is not instantaneous throughout the magma/lava (leading to enhancement or depletion in various elements) and since temperature is not uniform throughout the solidifying magma/lava (leading to inhomogeneity in the amounts of various mineral types), whole-rock tests on single-source igneous rocks do work and are done.

From Dickin's Radiogenic Isotope Geology, 2nd edition, section 3.2.2:

"Another development of the Rb-Sr method (Schreiner, 1958), was the analysis of co-genetic whole-rock sample suites, as an alternative to separate minerals. To be effective, a whole-rock suite must display variation in modal mineral content, such that samples display a range of Rb/Sr ratios, without introducing any variation in initial Sr isotope ratio. In actual fact, perfect initial ratio homogeneity may not be achieved, especially in rocks with a mixed magmatic parentage. However, if the spread in Rb/Sr ratios is sufficient, then any initial ratio variations are swamped, and an accurate age can be determined. Initial ratio heterogeneity is a greater problem in Sm-Nd isochrons, and is therefore discussed under that heading (section 4.1.2). Schreiner's proposal actually preceded the invention of the Rb-Sr isochron diagram, but some of his data are presented on an isochron diagram in Fig. 3.4 to demonstrate the method.


Fig. 3.4. Rb-Sr whole-rock isochron for the "red granite" of the Bushveld complex, using the data of Schreiner (1958). ...

Schreiner, G. D. L. (1958). Comparison of the Rb-87/Sr-87 ages of the Red granite of the Bushveld complex from measurements on the total rock and separated mineral fractions. Proc. Roy. Soc. Lond. A. 245, 112-7"

(By a stroke of luck, the Royal Society Archives are open now, but that link won't work after December).

Note "especially in rocks with a mixed magmatic parentage", clearly meaning that the method applies to rocks with single magmatic parentage.

And, from section 4.1:

"This equation has the same form as that for Rb-Sr (section 3.2) and can be plotted as an isochron diagram. However, because Sm and Nd have very similar chemical properties (unlike Rb and Sr), large ranges of Sm/Nd in whole-rock systems are rare, and in particular, low Sm/Nd ratios near the y axis are very rare. Therefore, because of the difficulty of obtaining a wide range of Sm/Nd ratios from a single rock body, and because of the greater technical demands of Nd isotope analysis, the Sm-Nd isochron method was generally applied to problems where Rb-Sr isochrons had proved unsatisfactory. Many of these applications were also made before the U/Pb zircon method had reached its present level of development (section 5.2.2). Therefore some of these units have subsequently been dated to greater accuracy and precision by the U/Pb method. However, it is important to review a few case studies to show the development of the method."

 
Quote
You have to put it in very simple terms for AFDave.

Oh, yes.
 
Quote
One wonders if he will acknowledge the clear statement of the history of which method was most popular in radiometric dating.  Maybe AFDave will get Tyred of it.

 :p

My bet is that he won't acknowledge it.

  
The Ghost of Paley



Posts: 1703
Joined: Oct. 2005

(Permalink) Posted: Sep. 18 2006,07:22   

Crabby:

 
Quote
We don't even need to discuss pre Clovis sites to blow your 'merican history starts with fundy white immigrants wiping out the local inhabitants view of American History (much less the History of the Universe).

Let's add racist to moron and willfully ignorant liar!


Ahhh....you did elaborate. Too bad the explanation's silly: the history of America is not congruent to the history of North America. Your hatred of the West whines through loud and clear, however.....

--------------
Dey can't 'andle my riddim.

  
JonF



Posts: 634
Joined: Feb. 2005

(Permalink) Posted: Sep. 18 2006,07:24   

Quote (Ved @ Sep. 18 2006,12:53)
RM doesn't exist in a vacuum.

Oh, Davie can't even conceive of considering the interconnections and correlations among all branches of science.  His only hope, futile though it is, is to consider each teeny subset in isolation.

  
afdave



Posts: 1621
Joined: April 2006

(Permalink) Posted: Sep. 18 2006,07:34   

WHOLE ROCK ISOCHRON "DATING" WAS DISCREDITED LONG AGO AND I DIDN'T EVEN KNOW IT ... SILLY ME (AND SILLY YOU)

(Refuted by a couple of Creationists *gasp* and subsequently discarded by the Godfather ... Brent Dalrymple himself)



So here's where we are in our study of the Isochron Method of dating rocks ... we have looked at a hypothetical set of charts which are very good because they really help you understand the logic.  And yes, they are from the RATE books.  (But don't buy them ... they might destroy your comfy worldview)  We are looking at whole rock isochrons first, then we will look at mineral isochrons.  Jon is correct that (at least from this real world example) the assumed Initial Daughter Ratio is closer to 0.7 for the Rb/Sr analyses.



We might just as well continue our discussion with this real world example.  But before we continue with that example, let's consider a statement made by JonF ...  
Quote
You bet your bippy that, if you go buy a furnace and melt some rock and then let it cool, your 87Sr/86Sr ratio will be the same for any sample and your 87Rb/86Sr ratio will NOT be the same between samples.  Absolutely guaranteed.
 Jon made this statement and then went on to explain the size difference between Rb and Sr.  Jon's statement that the atoms are different sizes is correct (I think he meant to say radius, not diameter ... my chart shows 1.48 as the radius for Rb+), however, I don't think size matters in regard to our present question (Sorry, Godzilla).  Certainly Rb atoms are going to be emplaced within crystal structures differently that Sr atoms because of their difference in size.  

But that is not the issue.  

The issue is this:  If a mass of lava is thoroughly mixed, then the atomic size difference does not matter.  Everything is mixed thoroughly and Sample 1 should have the same composition as Sample 2, and Sample 3, etc.  Yes, the Rb will be emplaced into the various mineral crystal structures differently than the Sr is emplaced, but the different emplacement should operate the same in all samples.  And I think Tracy is right.  If this is the case, you will have single point on your isochron diagram which of course is meaningless WRT an age calculation.

I did some more reading on this topic and I found some interesting things ...

Here's the Talk Origins article on the issue, complete with an animated GIF by someone named Jon Fleming (I'm guessing this is our own famous JonF?) ...

http://www.talkorigins.org/faqs/isochron-dating.html

The article does a wonderful job explaining the theory of the Isochron Method ... too bad that the fundamental assumptions appear to be wrong ... and apparently even Dalrymple cannot defend them anymore.

The following article sums up the fatal flaw with Whole Rock Isochron dating ... interestingly, Talk Origins doesn't even mention this article despite the fact that Dalrymple tried unsuccessfully to refute it.  I suppose it is an embarrassment to Talk Origins and they would rather try to refute some less competent writers ... such as Gill and Zheng.  (I'm not saying Gill and Zheng are incompetent ... I have not read them ... but apparently TO does.)

Let's take a look at the William Overn article found here ...

http://tccsa.tc/articles/isochrons2.html

 
Quote
ISOCHRON ROCK DATING IS FATALLY FLAWED

by William Overn

ABSTRACT
Radiometric rock dating, the methodology of determining the date of formation of a rock sample by the well-established rate of decay of the isotopes contained, depends on accurately determination of the starting points, the original concentrations of the isotopes. Many methods of estimating these beginning concentrations have been proposed, but all rest on tenuous assumptions which have limited their acceptance. This paper attempts to show that the Isochron-Diagram method contains a logical flaw that invalidates it. This most accepted of all methods has two variations, the mineral isochron and the whole-rock isochron. The logically-sound authenticating mechanism of the mineral isochron is applied to the whole-rock isochron, where it is invalid. The long-term stability of the whole-rock is applied to the mineral, where it is inappropriate.

When the isochron data are the result of the rock being a blend of two original species, the diagram is called a mixing line, having no time significance. This paper shows that all whole-rock isochrons are necessarily mixing lines. It is noted that by analogy the mixing-line logic casts strong suspicion on the mineral isochron as well. Since only whole-rock isochrons play a significant role in the dating game anyway, isotopic geochronology can be rather generally discredited.

Introduction:
Thanks mainly to the fact that they appear to be so constant, the decay rates of radioactive materials have become the primary mechanism for attempting to discover the age of rocks.[5,16] In addition to a constant rate of variation, however, any timing mechanism must also have a calibrated beginning point. A number of methods have been tried to calibrate the "radiometric clock". But they have all required unprovable and apparently unwarranted assumptions. Faure, in his textbook [9] refers to all of them as "assumed values" except for those obtained by the "isochron", or similar linear method.

The linear methods are several, and have in common the reduction of the data to a set which can yield a straight-line plot. Many exceedingly detailed descriptions of these methods are available.[1,2,5,16] A summary description of the Rb-Sr isochron is included below.


ARNDTS AND OVERN RAISE THE "BE" FLAG (BE stands for JonF style "Bovine Excrement")
 
Quote
Arndts and Overn alerted the creationist community to the fact that in spite of the mathematical rigor of the isochron, it also has unwarranted assumptions, and the data carefully gathered and processed to indicate immense ages can more appropriately be dismissed as indicating the recent mixing of two or more magmas.[1,2,3]


DALRYMPLE, THE FAMOUS CHAMPION OF RM DATING TRIES TO REFUTE ARNDTS AND OVERN
Quote
Dalrymple[6] challenged our analysis with five points, all of which were promptly and thoroughly refuted.  (Here) http://tccsa.tc/articles/isochrons.html[4]


DALRYMPLE DODGES THE BULLET HAVING BEEN THOROUGHLY REFUTED.
Quote
In Dalrymple's latest book [7] he ignores the entire issue of the whole-rock isochron, only defending the mineral isochron.


Wow ... did you catch all that so far?  A couple of creationists (leading the way in the search for truth as usual), blow the whistle on "Whole Rock Isochron" dating and show it is fatally flawed.  Dalrymple cannot disagree, so he ignores it and promotes "Mineral Isochron" dating.  Talk Origins has to be aware of this, but does not even mention it.  Why?  Too much good ammo for creationists, maybe?

This would explain why the 2006 Encyclopedia Britannica has this to say ...  
Quote
Rubidium–strontium (Rb–Sr) dating was the first technique in which the whole rock isochron method was extensively employed. Certain rocks that cooled quickly at the surface were found to give precisely defined linear isochrons, but many others did not. Some studies have shown that rubidium is very mobile both in fluids that migrate through the rock as it cools and in fluids that are present as the rock undergoes chemical weathering. Similar studies have shown that the samarium–neodymium (Sm–Nd) parent–daughter pair is more resistant to secondary migration but that, in this instance, sufficient initial spread in the abundance of the parent isotope is difficult to achieve.

"dating." Encyclopædia Britannica. 2006. Encyclopædia Britannica Online. 18 Sept. 2006
<a href="<http://www.britannica.com/eb/article-69759>." target='_blank'><http://www.britannica.com/eb/article-69759>.</a>


Overn continues ...  
Quote
There is sound logic supporting the mineral isochron, but another fatal flaw. Individual mineral crystals are not closed systems. Even over the few thousands of years available in the young-earth paradigm, they are insufficiently stable to give acceptable data to the geochronologists.


Overn describes the Rb-Sr Method
 
Quote
The Rb-Sr Isochron Method
Rubidium and strontium occur as trace elements in many common rock types. Rubidium has two isotopes. 85Rb (stable, abundance 72%) and 87Rb (radioactive). 87Rb decays to 87Sr with a half-life of (approximately) 48.8 billion years. Strontium is stable in all natural forms, and in addition to the radiogenic 87Sr (7%), has isotopes 88Sr (82%), 86Sr (10%), and 84Sr (<1%).

The general method of dating is to take several samples of the rock, to determine the ratios of the Rb-Sr isotopes in each, and by simultaneous equations determine the probable beginning points for each, from which the age may be determined.[16]

For the sake of compatibility with the available laboratory instruments, the specific ratios chosen are 87Rb-86Sr and 87Sr-86Sr. The algebra is equivalent to a simple straight-line diagram as in Figure 1. where points a, b, and c represent the samples.



Here is graphically represented the fact that the amount of daughter isotope increases as the amount of parent increases in the sample. The magnitude of that increase (i.e. the slope of the line) depends on the time allowed for the decay process to transpire, or the age of the rock. If we extrapolate down the line to the zero intercept, we have a representation of a sample with no parent isotope to contribute to the daughter concentration. This must represent the initial daughter concentration.

The slope is the age and the intercept is the initial daughter ratio. The scheme is mathematically sound. We must examine the assumptions.

For a problem to be solvable by simultaneous equations there must be as many independent equations as there are unknowns. The unknowns are the original 87Sr-86Sr ratio for each sample and the age of each sample. [THIS IS WHAT I SAID, REMEMBER?]Each sample gives one equation, but introduces two additional unknowns. Regardless of the number of samples, there are never enough equations to cover all the unknowns.[16] These problems must be resolved by the assumptions.

Assumption: The same age
It is assumed that all samples analyzed together are the same age. The word "isochron" (from the Greek "same time") symbolizes that. We do not dispute this assumption.

Assumption: The same initial strontium ratio
If all initial 87Sr-86Sr ratios in the system are assumed to be the same, the scheme can be made to work,[YES, THIS IS WHAT THEY DO ALRIGHT ... THAT'S WHAT I'VE BEEN SAYING] as the unknowns are reduced to two, the common age, and the common strontium ratio. Any two samples may now introduce the required two equations, and any more beyond that will simply improve the accuracy and the confidence level. This assumption is outside the experience based on field data, however, where the general case is that every sample has its own unique ratio.[DID YOU HEAR THAT?  SO MUCH FOR JONF SAYING ALL SAMPLES HAVE THE SAME RATIO ... I DID NOT THINK THIS COULD BE TRUE.] However, it can be rationally assumed that each sample we find has its own age and its particular rubidium concentration, which over time may have imparted a unique portion of daughter isotope. The assumed uniform strontium ratios should certainly be valid when applied to a rock system solidifying from a uniform homogenized melt. We must emphasize, however, that this enabling assumption must fail in the absence of an initial homogenized melt.[AND I THINK WE HAVE NOW ESTABLISHED THAT THIS SITUATION ONLY YIELDS ONE DATA POINT, WHICH IN TURN DOESN'T GIVE US ANY "AGE" INFO]

Assumption: A "closed" system
If isotopes have migrated in or out of the sample during the aging period, the resulting data have no time significance. Isochrons are thought to be self checking in this regard, since with several samples an open system with random migration should scatter the points off of the straight line. Indeed, it often happens that there is a scatter of data, rendering the isochron worthless. But there are many occurrences of isochrons having acceptably straight-line form that are also rejected. Often "metamorphism" is cited as the probable cause, the system having opened, either partially or completely resetting the clock. [11,19] In order to assure an acceptably closed system, samples as large as 1 meter cubes have been suggested.[20] The assumption of a closed system for many of the isochrons, if they have not been questioned by the geochronologists, will not be challenged here. We note that these are generally obtained on the samples of larger dimensions, that is the whole-rock isochrons.

Assumption:  Independent equations
If the equations are not independent, the problem cannot be solved. This would be the case where all samples on the diagram plot on a single point. Although the single point on the diagram is valid, there is no way of finding a slope or intercept. If the melt were initially homogeneous and remained closed, it could be expected still to be homogeneous, and yield that single-point isochron. This should be the general case of the whole-rock isochron.

The need is to find samples with a variety of initial rubidium content but still having initial strontium ratios that are known to be uniform. The assumed initial homogeneous melt cannot be expected to give whole-rock samples with variable rubidium, but the assumed uniform 87Sr-86Sr ratios demand such an initial homogeneous melt.


So I hate to sink your ship again ... I know it's painful, but the road to recovery always involves first admitting you have been wrong, so there's really no other option for you.

Note that most of the dates out there are "whole rock" dates ... or at least they were at the time this was written ... then Overn goes on to talk about the "Mineral Isochron" method which according to Dalrympe supposedly solves everything ...

 
Quote
The mineral isochron solves the dilemma. The mineral crystals have done the job in an elegant way. Crystals naturally form around a specific chemical composition, each atom occupying its naturally-assigned site. Foreign atoms just don't fit, either electrochemically or physically, and are strongly rejected. Depending on its concentration in the melt, a foreign element may have more or less acceptance in a crystal, based on its chemical and physical resemblance to one or another of the normal host elements. As the crystals form, each different mineral type accepts a different trace level of rubidium and of strontium. Because of their individual unique chemistry they each extract a different amount of rubidium and of strontium from the melt. The crystals of the individual minerals are used as the rock samples in the mineral isochrons.

MIXING
Often an isochron yields an unacceptable slope, indicating an age much too young or much too old to be compatible with the accepted model. [19] Frequently the slope is negative.[18,14] A common explanation for these cases is "mixing". It has always been recognized that the same straight-line plot as the isochron can be achieved if the original melt were a mixture of two original homogenized pools.[12] Figure 1. may also be used to illustrate this case. If points a and c are the compositions of the two original pools that partially merged to form the melt, any sample from the melt will occupy a place on a straight line between them, such as point b. No sample will be found above a or below c. Such a "mixing line" has no time significance, and the textbook warns to be wary of accepting such mixing as a true isochron.

Faure's text also proposes a test for mixing. [13] If a plot of 87Sr-86Sr vs 1/Sr (the concentration of strontium) shows a linear relationship, then mixing is indicated. A brief study conducted in 1981 showed a high degree of correlation to this mixing test in the isochrons being published.[3] A subsequent public dialog between Dalrymple[6] and Arndts & Overn [4] concluded that although the mixing test is strongly indicative of mixing, there are circumstances under which mixing would not be detected by such a test, and others wherein the test could give a false indication of mixing. The caution for the geochronologist would be to suspect any isochron, since there is no way to rule out mixing.

It is now clear, however, that there is at least one positive test for mixing. It is the whole-rock isochron itself. If the whole rock yields samples that give a linear plot, whether the slope is positive or negative, or whether the slope signifies an age that fits a preconceived model or not, there is no other known mechanism outside of mixing to which the data may be rationally ascribed.

Discussion
Mixing is an unfortunate misnomer that has become popular for describing rocks formed from two or more original melts, or from a melt becoming contaminated by isolated incorporation of local rock. Understand it to mean partial mixing, with resulting heterogeneity. Complete mixing would result in homogeneity, and would give only a single point to plot. No curve of any kind, nor even a scattering of points would occur.

This homogeneity is the assumed starting point in the history of the rock being dated. It then solidifies. But now, years later, we dig up 6 adjacent meter cubes of the rock, and discover that the normalized ratio of the parent (and incidentally of the daughter) is different in each cube, sufficient to plot as an "isochron". How can we rationally accept the assumed initial homogeneity? We can not.

What is needed but missing in the whole rock isochron is a mechanism to establish initial homogeneity, and then to extract heterogeneous samples. The mineral crystals do the job in an elegant way. Each type accepts a different level of contamination of the parent isotope, chemically determined. One cannot rationally extend this process back to the whole rock. It has been tried, but there is a fallacy . [5,20]

As we stated in 1986: [5]

The whole-rock isochron is justified on the basis that migration of the isotopes in a metamorphic event may be confined to distances of perhaps 1 cm. This is much larger than the average crystal size. Thus the original constituents of each crystal will lie nearby. By taking samples of 100-cm dimensions, one could assure that the entire content of the original crystals are well represented by the sample, with very small error. However, this matrix is the original melt that was theorized to be homogeneous. The ability to find differences in the rubidium content among the samples violates the assumption of original homogeneity. Original inhomogeneity is the only possible explanation: in other words, mixing.

This method of justifying the whole-rock isochron on the basis of the mineral is logically unsound. Within the larger matrix the tiny crystals may incorporate discrete trace elements and return them over time. But they are powerless to alter the composition of the whole-rock matrix.

It is claimed that fractional crystallization of magmas and separation of crystals from the remaining liquid result in suites of comagmatic rocks of differing composition. [10]. This may be true, but there is no experimental evidence that this can generally be applied to trace elements that are foreign to the crystals. Add the fact that trace elements are not securely held by crystals until temperatures are well below the melting points, and this postulate falls far short of explaining the variation in rubidium in whole-rock isochrons. Mixing is much preferred, particularly when it is noted that many data sets have negative slope, where mixing is always the accepted explanation. Often the negative-slope data pertain to large formations that particularly fit the hypothesis of slow cooling from a melt. [15,18]

In the case of the mineral isochrons the scheme postulates an initial homogeneous melt, represented by a single point on the diagram. As the crystals form, their differential solubility will move their individual points on the diagram horizontally , different distances. (Only horizontally, since the vertical is a ratio of two isotopes of the same element).[THIS IS WHAT JONF WAS TALKING ABOUT IN HIS DISCUSSION OF ATOMIC "DIAMETERS" ... THE "T.O." ARTICLE ALSO SHOWS A DIAGRAM OF THIS ... IT IS A VALID POINT, BUT DOESN'T SALVAGE THE LOGIC BEHIND WHOLE ROCK ISOCHRONS] The large volume of whole-rock isochrons, however, shows the general case to be an initial heterogeneous melt represented by the kind of diagram published as an isochron, and which we conclude is actually a mixing line.[WHAT I WAS TRYING TO TELL YOU] Any point in the melt can be represented as a point on the straight line. When mineral crystals form, each crystal will move its point off the straight line in one or the other horizontal directions. The result is a scattering of the points. The geochronologist discards it as one of the following:

A three or more part mixture,

Subsequent metamorphosis,

Not a closed system: In this case he recognizes that crystals really cannot be expected to be a closed system. They tend to continue to reject contaminants long after formation, the mobilities of foreign elements in crystals being a whole school of scientific study. The retention of trace elements in crystals is so inadequate that it has been possible to construct "Isochrons" from various parts of the same crystal.[17] It is common that when the mineral isochron fails, the geochronologist then produces a whole-rock isochron from the same formation.

The ability to obtain a whole-rock diagram, straight-line or not, can be considered proof that the data represent a "mixing line" rather than an "isochron". If mixing has not occurred, and the system has remained closed, then the whole-rock data must all lie on a single point. In fact, even if the whole-rock data show scatter, either mixing is indicated -- but of a complex nature, with more than two components -- or there have been subsequent alterations described as the system being open, or both.

Has any legitimate isochron ever been formed? It is improbable. There is ample evidence for mixing. Any "isochron" could be mixing. There is no way to rule it out. All whole-rock "isochrons" are mixing, and they are approximately 90% of all published. Many of the remaining (mineral) "isochrons" have a whole-rock point located close enough to the straight line to discredit them. Why should we expect any of the others to be "true isochrons", since mixing has the strongest probability?


Wow ... 90% of all the isochron "dates" published are whole rock AND Dalrymple had no defense when whole rock dating was shown to be fatally flawed!!  This explains why JonF doesn't get very excited about whole rock isochrons.  I guess it also explains the following from EB ...  
Quote
Absolute dating > Major methods of isotopic dating > Uranium–lead method

As each dating method was developed, tested, and improved, mainly since 1950, a vast body of knowledge about the behaviour of different isotopic systems under different geologic conditions has evolved. It is now clear that with recent advances the uranium–lead method is superior in providing precise age information with the least number of assumptions. The method has evolved mainly around the mineral zircon (ZrSiO4).

dating." Encyclopædia Britannica. 2006. Encyclopædia Britannica Online. 18 Sept. 2006  http://www.britannica.com/eb/article-69767


EB goes on to describe how it is apparently not even good enough to analyze single zircon grains ... you have to remove the outer damaged "shell" of the zircon and analyze the tiny inner portion alone.    
Quote
More recently, it has been found that of all the grains present in a rock a very few still retain closed isotopic systems but only in their interior parts. Thus grains with a diameter comparable to that of a human hair, selected under a microscope to be crack-free and of the highest possible quality, have been found to be more concordant than cracked grains. In addition, it has been shown that most such grains can be made much more concordant by mechanically removing their outer parts using an air-abrasion technique (upper points in Figure 2).

dating. (2006). In Encyclopædia Britannica. Retrieved September 18, 2006, from Encyclopædia Britannica Online: [url]http://www.britannica.com/eb/article-69768 [/url]


Overn continues...  
Quote

If one possesses a strong faith in the antiquity of the rocks, one could rationally expect that an occasional mineral isochron is legitimate. But it would also require the whole-rock diagram to be concentrated in a single point. (Neither a straight line or scattered). Often a whole rock point is put on a mineral diagram. That does not meet the criterion. Several whole-rock samples must be obtained, using the same techniques required for the whole-rock method. Their individual data points must be identical, i.e. superimposed on the diagram. At that point mixing would not have been ruled out, but all available tests requiring mixing would have been eliminated.

In the dialog with Dalrymple [4] it was noted that he is unwilling to defend the whole-rock isochron. In his latest book [7] on the age of the earth he has included a section that describes the elegant process with which crystals (minerals) give the necessary heterogeneity to make the system work. He also shows why the mineral isochron cannot be relied upon for dating, but does not state that conclusion. He carefully avoids describing the whole-rock method, which leads the casual reader to conclude that it is validated by the same processes as is the mineral method. Nothing could be farther from the case. Dalrymple has seen our initial critique of the whole-rock method, [5] and is obviously reluctant to forthrightly claim any scientific merit for it. He has clearly sidestepped the issue.

Dalrymple [7] does not depend directly on isochron dating of rocks to date the earth, but rather on the lead-isotope ratios. He must be commended for his carefully pointing out the many assumptions involved. However, he finally ignores them and claims that the age has been determined within a very narrow margin.

His ultimate method is to take the radiometric ages of lead ores (Circa 2.6-3.5 Ga) and correct to the beginning. Again I point out that the "isochrons" used to date the ores, as well as those of the meteorites, that add so much to Dalrymple's confidence in the method, are most probably mixing. Note tables 7.4 and 7.5, [Ref 7] which give many meteorite ages. Almost all are whole-rock.

Additionally note that with all his enthusiasm for the isochron, Dalrymple characterizes the method as a "first approximation" [8]

As has been pointed out many times before, all radiometric methods including the linear-plot techniques have been effectively "calibrated" to the fossil dates by selecting among the discordant data those that fit the accepted stratigraphic model. [THIS IS WHAT I TOLD YOU LONG AGO][16] Since the proponents of the isochrons don't take them at face value, others should by equally wary.

See also: "Still No Proof For Ancient Age -A Response" by W. M. Overn and Russell T. Arndts
A technical analysis of "Isochrons" as defended by Dalrymple against creationist criticism, showing that despite mathematical sophistication, they are unreliable and are calibrated to "known ages" using the geologic column.

BIBLIOGRAPHY


[1] Arndts, R. & Overn, W. 1981 "Pseudo Concordance in U-Pb Dating" Bible-Science Newsletter 19(2):1.

[2] Arndts, R. & Overn, W. 1981 "Isochrons" Bible-Science Newsletter 19(4):5-6.

[3] Arndts, R., Kramer, M. & Overn, W. 1981 "Proof of the Validity of the Mixing Model" Bible-Science Newsletter 19(8):1.

[4] Arndts, R. & Overn, W. Proceedings of 1985 Creation Conference North Coast Bible-Science Association, Cleveland, Ohio.

[5] Arndts, R. & Overn, W. 1986 "Radiometric Dating -- An unconvincing Art" Proceedings of the First International Conference on Creationism Vol 2, Creation Science Fellowship, Pittsburgh, Pennsylvania, pp 167-173.

[6] Dalrymple, G. B. 1984 "How Old is the Earth? A Reply to {at}Scientific Creationism' " Proceedings of the 63rd Annual Meeting of the Pacific Division AAAS 1(3):84-86

[7] Dalrymple, G. B. 1992 The Age of the Earth

[8] Ibid p. 402.

[9] Faure, L. 1977 Principles of Isotope Geology John Wiley & Sons, Inc. New York, New York. p.78

[10] Ibid p. 79.

[11] Ibid p. 83-87.

[12] Ibid p. 97-105.

[13] Ibid p. 101.

[14] Jager, E. & Hunziker, J. C., eds, 1979 Lectures in Isotope Geology Springer-Verlaug, Berlin, Heidelberg and New York, p. 36

[15] Ibid p. 142-144

[16] Overn, W. 1986 "The Truth About Radiometric Dating" Proceedings of the First International Conference on Creationism Vol 1, Creation Science Fellowship, Pittsburgh, Pennsylvania, pp 101-104.

[17] Scharer, V. & Allegre, C. 1982 "Uranium - Lead System in Fragments of a Single Zircon Grain" Nature 295 (Feb.): 585

[18] Tilton, G. R. & Barreio, B. A. 1979 "Origin of Lead in Andean Calc-Alkaline Lavas, Southern Peru" Science 210, 1245-1247

[19] Woodmorappe, John 1979 "Radiometric Geochronology Reappraised" Creation Research Quarterly 16, 102-129

[20] York, D. & Farquhar, R. M. 1972 The Earth's Age and Geochronology Pergamon Press, New York, pp. 80 ff.





*********************************************************

And so, ladies and gentlemen, (are there any ladies?) we have come to the end of yet another chapter in AFDave's Creator God Hypothesis ... I have seen overwhelming evidence for exactly what I expected to see ...

MOST RADIOMETRIC DATES ARE NONSENSE

I suppose I will take a day or so and look at the "latest and greatest" methods (which I am seeing are really not the latest and greatest at all ... they are just increasingly desperate attempts to stay one or two steps ahead of the creationist whistle blowers, all the while hoping that the general public will never really understand what's really going on ...

THAT DEEP TIMER'S ARE MISTAKEN ABOUT THE AGE OF THE EARTH

How does this help my Hypothesis?  Simple.  It removes the "credibility" of RM "dating" methods and creates a vacuum.  Into this vacuum steps the Biblical (historical) explanation.  Many have asked how I would date the layers of the Grand Staircase.  And the answer is:  from the historical record of Genesis.  There is a record of "the fountains of the deep" being broken up and a global flood occuring.  When did this occur?  Probably around 2300 BC based on genealogical records.  If some were missing the date moves back some, but there is no evidence that any are missing.

***************************************

SE...  
Quote
During the flood there would be no rivers or dry land though. Wasn't everything covered by water? Surely water action would tend to smooth rock formations during a global flood, not cut canyons.

So what is next? The canyon was cut after the flood receded by trapped flood water?


Here's a likely scenario for how the Grand Canyon was cut ...



... and here's a likely timeline of the Flood Events ...



--------------
A DILEMMA FOR THE COMMITTED NATURALIST
A Hi-tech alien spaceship lands on earth ... DESIGNED.
A Hi-tech alien rotary motor found in a cell ... NOT DESIGNED.
http://afdave.wordpress.com/....ess.com

  
Ved



Posts: 398
Joined: Oct. 2005

(Permalink) Posted: Sep. 18 2006,07:37   



"What??? Someone here hates The West? Lemme at 'em!"

  
Stephen Elliott



Posts: 1776
Joined: Oct. 2005

(Permalink) Posted: Sep. 18 2006,07:42   

Quote (afdave @ Sep. 18 2006,12:34)
***************************************

SE...    
Quote
During the flood there would be no rivers or dry land though. Wasn't everything covered by water? Surely water action would tend to smooth rock formations during a global flood, not cut canyons.

So what is next? The canyon was cut after the flood receded by trapped flood water?


Here's a likely scenario for how the Grand Canyon was cut ...



... and here's a likely timeline of the Flood Events ...


I do not think you answered my question.

If God caused the flood and then caused the waters to recede...

Was the water left that caused the canyon a mistake, an oversite or deliberate?

  
oldmanintheskydidntdoit



Posts: 4999
Joined: July 2006

(Permalink) Posted: Sep. 18 2006,08:01   

Quote (The Ghost of Paley @ Sep. 18 2006,12:22)
Crabby:

 
Quote
We don't even need to discuss pre Clovis sites to blow your 'merican history starts with fundy white immigrants wiping out the local inhabitants view of American History (much less the History of the Universe).

Let's add racist to moron and willfully ignorant liar!


Ahhh....you did elaborate. Too bad the explanation's silly: the history of America is not congruent to the history of North America. Your hatred of the West whines through loud and clear, however.....

and you aredoing what again, trying to say that the sun goes around the earth or something?

I think that before you speak of other peoples *silly* explanations you might want to have a look in the mirror.

now, run along.

--------------
I also mentioned that He'd have to give me a thorough explanation as to *why* I must "eat human babies".
FTK

if there are even critical flaws in Gauger’s work, the evo mat narrative cannot stand
Gordon Mullings

  
Bing



Posts: 144
Joined: Mar. 2006

(Permalink) Posted: Sep. 18 2006,08:25   

Quote (afdave @ Sep. 18 2006,12:34)
... and here's a likely timeline of the Flood Events ...


Very nice picture Dave, but let's pick a nit here, shall we?

Your cartoon allows 1 day for continental drift.

Now various sources give a figure of roughly 3500 miles for the average width of the Atlantic Ocean.  Can we do a little basic arithmetic?  

3500 miles / 24 hours = 145.8333333 miles/hour.

Dave, this is more than 2X the legal speed limit on your nation's highways.

Why don't we break this down a little further?

145.8333333333 / 60 minutes = 2.430555555 miles/minute.

Reducing this even further we get a value of 213.88889 feet per second!  That's 2/3 the length of a football field every second!

How much energy does your car require to travel 70 mph?  How much energy does it take for your car to travel 145 mph?  

How much energy would it take for a continent to travel 145 mph through water?  Think back to your fluid dynamics classes from first year engineering Dave, come up with a number and get back to us, OK?  What would that energy do to the water surrounding it Dave?  Do you think the earth would even have cooled down yet, 4300 (alleged) years later?

  
BWE



Posts: 1902
Joined: Jan. 2006

(Permalink) Posted: Sep. 18 2006,08:27   

Dave,

The problem with the isochron method deconstruction you are using is isolation. Anyway, Rm dating is not normally done in a "vacuum" (That genesis could step into). Dating is not any single discipline. Besides missing the point of peer revue, you are also missing the forest for the trees. Rm dating is a laboratory issue. A well managed lab can show you results and tell you what they mean and how they got them.

i.e. I send my rock over to a lab here in town. I say something like, "I need you to do a date on it and tell me if x, y or z are present."

They say something like "Sure we have the equipment for dating method x and we will use method a to determine the presence xy or z."

"Great, thanks. What are the tolerances?"

Then we go through it all and it turns out that knowing the date becomes really important. Then, I will go back to the place I got my sample and try to see if lots of other methods agree. If one doesn't, and I ignore it when I include the "date" in my report, I will get called on it and have to go back and do it all over again until I get dates in agreement. Doesn't matter what my answer is, just that I have double checked my work. True, I would check the one that didn't agree first, but if I couldn't get it to agree, I would have to find out why. This could quite possibly lead me to check all my other dates too. (I actually would be likely to be checking sediment rather than igneous rock but that just changes a few of the techniques and methodologies.)

Core samples are also pretty good dating methods. Want to talk about core samples? I'm really tired of Rm dating.
:)

--------------
Who said that ev'ry wish would be heard and answered
When wished on the morning star
Somebody thought of that, and someone believed it
Look what it's done so far

The Daily Wingnut

   
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