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It is obvious you have no clue what radiometric "dating" is capable of. There is no magic box that pops up a date when an object is inserted. All it tells us is the level of certain isotopes.
JM: Simplistic, but not off the wall.
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What this tells us is pure speculation. Unless you have a time machine you have to assume that you know the original level of the isotope and if the sample was affected by any outside influence.
JM: Now, I'm not exactly sure who you are lecturing. The initial isotopic composition can be determined in many cases using the isochron method. The presence of excess argon or argon loss can be determined by doing stepwise release. In the U-Pb system we can see Pb loss because the age determinations will fall off concordia. These 'problems' are well known to geochronologists who have developed methods to test for such problems. I suggest you read Brent Darymples excellent book "Age of the Earth" or visit Dr. Wiens site
Radiometric Dating A christian's guide to radiometric dating.
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Sedimentary rock is not subject to this type of testing. Lyell made up dates for geologic layers before anyone dreamed of radiometric testing. Out of thin air!
JM: First, there were never any absolute ages assigned to the early geologic systems. There were only relative ages assigned to the sequences based on very simple and non-controversial observations. If you can document Lyell or anyone else of his time assigning an absolute age to a rock, I would love to hear about it. Today sedimentary rock can be dated using isotopic methods. Specifically, the U-Pb system has proven to be useful in dating certain types of sedimentary rocks. In other cases, the ages of the sedimentary rocks are bracketed by direct dating of ash beds above and below the sedimentary sequence. Here are a few examples of how this dating is accomplished:
U-Pb SHRIMP ages of Neoproterozoic (Sturtian) glaciogenic Pocatello Formation, southeastern Idaho
Author Fanning, C Mark; Link, Paul Karl
Source Geology (Boulder), vol.32, no.10, pp.881-884, Oct 2004 Dates sed sequences via bounding igneous rocks
C, O, Sr and Pb isotope systematics of carbonate sequences of the Vindhyan Supergroup, India; age, diagenesis, correlations and implications for global events
Ray, Jyotiranjan S; Veizer, J; Davis, W J
Precambrian Research, vol.121, no.1-2, pp.103-140, 28 Feb 2003Pb-Pb age of carbonate that matches U-Pb dating of ash beds.
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It is circular reasoning-the fossils date the rocks -the rocks date the fossils.
JM: It sure is and this is why it's never done.
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Creation scientist as well as many honest evolutionist scientist have found thousands of cases that radiometric dating -if you assume it is valid-disproves the billions of years theory.
JM: Not a single credible instance of such a thing has ever been documented.
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For instance lava flows at Mt. St. Helens that occurred in 1980 have tested at 300k years old. This has happened with lava flows all over the world. If any testing disagrees w/ accepted dating, which is the vast majority of them, they a must be contaminated.
JM: Was the rock dated, or was it inclusions within the rock? You see contamination can occur and requires care. The samples dated by Austin are known to contain older remanents of rock incorportated into the magma. Austin knew this (since his paper cites a reference documenting the xenoliths) so it was a bit of a farcical attempt to discredit dating.
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Unless the rocks were kept in a lead shield they are all contaminated.
JM: Reference please to support the relevance of this assertion to radiometric dating?
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Without the billions of years the evolution hypothesis flies out the window.
JM: Evolution is both a theory and a fact. It is not just a hypothesis. I suggest before you lecture others about their supposed misunderstandings that you clearly understand the methods yourself. It's not required of course, but it gives you more credence on these boards.
Cheers
Joe Meert
This message has been edited by Joe Meert, 02-27-2005 09:06 AM
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