Reply: The compilation of ages include dozens of Pb-Pb results. Even if they didn’t, I would still disagree. The compilation of ages, in and of themselves, provide the evidence sufficient to prove my point: imprecision and contradictory results.
Age-dating is not within my area of expertise, but I am confused as to how compiling a list of ONLY discordant dates is going to give you anything BUT discord. It doesn't really seem to say anything other than, "age-dating can result in discordant dates."
Well, we already know that!
It seems to me all you've done is calculated some sort of biased standard deviation using questionable data. Questionable because I can't see the actual data and how it was collected.
As JonF stated, before anyone can critically review your proposal, you're going to have to show exactly how and from where the numbers you used were collected. So you are probably going to have to write up that long summary.
Something that hit me after reading this post (in fact the very same statememt Dr. Cresswell quoted ): discordant dates are often listed in papers because event those dates tell us (mainstream geoscientists) something about the geologic history of an area. It can tell us about metamorphism, re-heating due to igneous events, etc. Discordant dates to us are just as important as concordant dates. While YECs may scoff at our use of them (lamenting upon our desire to find anything to support our biased mindset - or something along those lines) they are still out there in published papers for anyone to compile.
This message has been edited by roxrkool, 12-08-2004 12:19 PM
There are many instances of dates with good internal consistency being rejected as not giving the correct age of a rock because they conflict with accepted values. In a Precambrian situation, K-Ar dates were much younger than the (presumed correct) Rb-Sr dates, and about the K-Ar dates McKee and Noble commented: "Continuous partial argon loss may have occurred. If this is the case, the consistency of these apparent ages is fortuitous."
In the example above, Woodmorappe misquoted McKee and Noble (reference 268) by omitting part of a sentence, without indicating this by ellipses, and by not completing their thought. What they actually wrote was (McKee & Noble, 1976, p. 1190):
Continuous partial argon loss may have occurred as a result of weathering or heating from deep burial, although neither phenomenon is apparent from field or petrographic studies. If this is the case, the consistency of these apparent ages is fortuitous. The consistency of the three K-Ar ages reported here suggests that the lower radiometric ages obtained by the K-Ar method may reflect an episode of heating about 800 m.y. ago.
This is a deliberate misquotation of McKee and Noble and this example alone would be enough to prevent publication of this paper in any reputable scientific journal.
This is enough for me to never view Woodmorappe as a professional scientist ever again. Where are his ethics?
And an excellent example of why any calculations based on Woodmorappe data are dubious at best.
AC, having read your critical analysis of the paper, all I can say is that you do not fully understand the complexities of igneous systems, nor what results after having been affected by outside influences. However, you are probably the FIRST YEC I have ever seen to present such an analysis and I respect you greatly for it.
First, and anyone correct me if I am wrong (read the paper and wrote this post quickly!), this study looked at mineral fractions and leachates - two different things. The important distinction to be made between mineral separates and the leachates is that the mineral separates are the actual (primary?) minerals themselves, sans alteration minerals (I presume), and the leachates are the alteration minerals that dissolved in solution from the collected minerals.
Although I wasn't too clear on their exact method, it seems that rock sample crushed, minerals were collected, separated, and then placed in a solution to leach out the soluble minerals. The minerals left after the leaching process are termed the "mineral fractions." The minerals in solution are the "leachates."
It appears the leachate gives an indication of the alteration minerals that are formed from the primary minerals (as a result of some event), and judging from the fact that they are discussing shock impact textures, it was likely/possibly an impact event.
Therefore there was a very good chance that they would have contrasting analytical results/isochrons - and they did. It was expected based on petrographic anaylyses of the rocks, NOT ad hoc rationalizations as you claim. The authors have evidence at hand that the rocks were subjected to some sort of alteration event.
Also, please note that the discordant results were not discarded, but included in the report as they tell an important story. You simply don't agree with their interpretation.
This message has been edited by roxrkool, 12-10-2004 09:02 PM
haha DUH!!! I read they were martian rocks and then totally spaced that off.
I'm still unclear as to the nature of the leachate parent material. I can't tell if they originate from actual alteration minerals or not, but PurpleYouKo's post made a lot of sense.
The paper reads as though it is part of a larger set of related research. I feel like I'm reading it out of context.
Oh yeah, I forgot to add that it's possible the shock textures are the result of having been ejected into space from Mars, too. There was likely an impact on Mars that caused the meteorites to be ejected in the first place.
Damn! Cora beat me to it.
This message has been edited by roxrkool, 12-10-2004 09:51 PM
This message has been edited by roxrkool, 12-10-2004 09:52 PM
Synopsis: We have completed Rb-Sr isotopic analyses on mineral fractions and leachates from the Martian meteorite LEW88516 (LEW). This meteorite is classified as a lherzolitic shergottite and is mineralogically and geochemically very similar to the other two lherzolitic shergottites ALH77005 (ALH) and Y793605 (Y79) [1,2,3,4].
According to a few talks I went to on Mars, I seem to remember a reason for studying Martian rocks is to learn a little about earth's earliest geologic history. Mars appears to have been preserved quite early in its geologic history and perhaps we could learn from Mars what's been erased on Earth.
Roxrkool: “It can tell us about metamorphism, re-heating due to igneous events, etc.”
Reply: You must understand that discordant dates cannot “tell us about metamorphism, re-heating due to igneous events, etc.” unless we use reliability standards consistently. We do not. Instead, we equate “discordance” with “metamorphism”, and “concordance” with “closed system”, effectively solidifying the conclusions of our experiments before they are even conducted.
You accuse mainstream scientists of arbitrarily assigning various degrees and types of alteration or mineralogy to rocks in order to explain away any discordant dates, but you have not supplied us with evidence that this in fact is true. We just can't take you word for it.
Please show how mainstream scientists are being inconsistent with their assigning of some rocks as metamorphosed, re-heated, altered, etc.
Even more convincing is the presence of young rock overlying directly upon Precambrian basement rock. Take these examples:
Tertiary found on Precambrian………………>4% Cretaceous found on Precambrian…………...>9% Jurassic found on Precambrian………………..4% Triassic found on Precambrian……………..>11%
This means that those who support geologic time must again resort to special pleading and rationalizations to explain how, in cases where Tertiary is found lying directly upon Precambrian, 480 million years of geologic time just happened to disappear; or for the other three examples given above – 410 million, 340 million, and 295 million years of alleged geologic time just happened to vanish into thin air.
Are you kidding me?
You made a good show of having a bit more geologic knowledge than most YECs, so this bit of ignorance comes as a surprise. Are you the same person?
This little analysis on your part is so flawed and ridiculous I have to wonder if you know ANYTHING about geology. Either that or you've convinced yourself the posters here are as ignorant or more ignorant than you of geologic processes. Unfortunately for you that is not the case and so it's rather annoying to have to read such patronizing nonsense.
All you've done above is point out large unconformities. Big deal! They are found everywhere in the rock record and a good geologist can explain their significance. Look around you. Some areas are being eroded and that eroded material is being deposited. It doesn't take a Ph.D. to figure out what unconformities are.
Well, the easiest person to fool is yourself, and the naturalists here have done a most remarkable job in their complete dismissal of the facts that I have demonstrated in this thread, which undermine some of the most critical foundations of geochronology.
There has been no "complete dismissal" of your 'facts.' People have asked you for clarifications and so far you have not done so. The only person dismissing anything (EVERYTHING!) is you - most likely because you are incapable of answering the questions put to you.
Additionally, you haven't undermined anything except your own credibility by posting the driveling nonsense found in your latest post.
This message has been edited by roxrkool, 01-01-2005 14:03 AM
edited for clarity and redundancy
This message has been edited by roxrkool, 01-02-2005 01:45 AM