How, exactly, is dating done?

As JonF mentions above, K/Ar dating is about the only method Creationists are willing to discuss. I'm sure we've all participated in discussions where the Creationists take the position that radiometric dating is flawed, and they invariably use K/Ar dating as the example. Evolutionists explain why initial Ar concentration isn't a problem and couldn't possibly cause millions of percent of error anyway, and then go on to mention the isochron and other methods that don't even have any initial daughter concentration problem. The Creationists rebut with more about K/Ar dating. The evolutionists explain again, and suggest again that the Creationists address how isochron and the other methods could all be wrong, and by identical amounts. The Creationists again rebut with more about K/Ar dating, and the cycle repeats. It would be a pleasant development to see Creationists actually address the other approaches.Even without bringing in the other methods and focusing solely on K/Ar dating, the case against radiometric dating is incredibly weak, and can only be maintained by YECs who still don't really grasp its principles. I have a feeling that its popularity on discussion boards is because organizations like ICR, CRS, AIG, etc, have spent a lot of ink addressing K/Ar dating, so there's lots of source material.--Percy

Not 100% true, but close. I and others had a discussion (on talk.origins) of isochron dating with an old-Earth young-life creationist that lasted from around January 2002 well into 2003 (and left her still convinced that the ages we get are not solidification/closure ages, but are rather some echo of the early Earth that survives through melting and mixing). (The long duration is misleading, since it took incredibly long to get most ideas across to her ... IIRC it took over a month to convince her that division by zero is undefined in the kind of math we use in dating).And, of course, the Woodmorappe book I mentioned "addresses" pretty much the gamut of dating methods.

Bookmarking.

I've got a question for you guys that seems to fit into this thread pretty well. Rei posted some specific events in which carbon dating should not be used, specifically volcanoes. My question is how do you know if a sample has been contaminated and therefore is unreliable. How do you know if a volcanic eruption has contaminated a sample that is supposedly 20,000 yrs old?

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I've got a question for you guys that seems to fit into this thread pretty well. Rei posted some specific events in which carbon dating should not be used, specifically volcanoes. My question is how do you know if a sample has been contaminated and therefore is unreliable. How do you know if a volcanic eruption has contaminated a sample that is supposedly 20,000 yrs old?

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I suppose by this you mean the idea that a volcano erupting close to a forest can give out large quantities of C02, which can be absorbed by them and thus give a false reading. Proposed first by Woodmorappe, I believe.Dead easy to spot. Remember trees are effectively alive only on the outside of the wood - the current growing ring. For all other growth rings, no more CO2 occurs. As a result, for carbon dating samples are taken from the rings - to date the tree's death from the outside. This can be checked by taking samples progressively further back to work back to the tree's initial seeding. If there was such an anomoly, the carbon dating results (from the inside out) would show a smooth age progression, then one (perhaps a few more) totally off the wall, followed (assuming the tree survived) by a resumption of the smooth trend.However, I'm not convinced this is a reasonable scenario. Even the most massive CO2 surge would very swiftly be diluted in the atmosphere. The tree would have to be virtually on top of the volcano: in which case it would almost certainly be killed before it had time to take up much (if any) of the CO2. Further, even given the survival of the tree, the cloud would dissapate so fast that only a small amount of anomolous CO2 would be taken up.So, in summary, my answer is the carbon dating would show an obvious anomoly if the event occured, but the liklihood of the event is, in any case, small.

I just read something about how all the water springs on the earth are showing contamination of MTBE, Its not like the rocks are not pourous, leaning that in some way elements are leaching, affecting not only the argon method but all the dating methods, in a proportional ratio, capillary osmosis, rain water causing bacterial gases, in the pourous rocks, when you factor in cationic and anionic forces in the soils, powered by the earth itself being an electon sink (earth ground), it should be obvious by the simple example in our day of all the spring waters thousands of feet into the ground, being contaminated by MTBE, and other pollutants in the surface waters, even the DNR is concerned about heavy metals in sewerage waste recycled back on farmers fields, because it will because of said forces it will become a part of the soils, etc...
P.S. Water is a solvent, it translocates minerals and redeposits them, in a proportional ratio, with capillary osmosis, bring these solutes into proximity with the mineral lattices, where the electon sink (earth ground) causes the very elements your dating to be drawn(anionic, cationic forces) into the mineral lattices over time in a proportional ratio, explaining how its possible to find instances where the dating methods appear to agree, it doesn't mean they are actually old, just that the leaching processes makes it appear to be, etc...

Gobbledygook.We don't date porous rocks, except for a very special few cases (such as diagenic xenotime dating of sedimentary rocks), in which the xenotime that is dated is a very small portion of the rock and is not itself porous.Isochron methods and concordia-discordia methods, by far the vast majority of methods used today, essentially always detect when samples have been affected by leaching or other changes since solidification (more technically, closure). Discordia dating can often supply a valid age even when the samples have been affected by such changes. These are age-diagnostic methods which almost always detect when the samples are invalid. This has been pointed out several times, and you have ignored it.In other words, your criticism is a pipe dream. It has no validity or grounding in the real world. Please do not offer criticisms until you have learned something about that which you are criticising. If you have questions we'll be glad to answer them, but your pronouncements are so far completely content-free.[This message has been edited by JonF, 01-13-2004]

I thought black granite was the least porous rock, that basalts are porous, don't you date the basalt lava rocks, that they say are porous, I realize some elements were tied up when they were heated, however, if the rocks are porous then water can flow through by capillary osmosis, reverse osmosis, with the forces of cationic and anionic forces draw elements out of the solutes into the mineral lattices, how can I believe that the rocks they say are the most porous are not porous, etc...
P.S. I believe they even seal the granite tops so they won't stain, though black granite seems to be near impermeable, etc...If all the wells show contamination, likely the rock basalts are pretty permeable, etc...http://www.trinitysprings.com/why.htm
The most compelling evidence of TRINITY's pristine state is the absence of tritium, the pervasive radioactive byproduct of nuclear testing which is found in all surface environments. TRINITY is also free from all other manmade pollutants such as the MTBE gasoline additive which is found underground throughout the United States at an alarming rate.[This message has been edited by whatever, 01-13-2004]

Yes, basalt is one kind of rock that is dated; but no, it's not particularly porous, and water does not flow through it to any great extent. It can act as if it were porous due to fracturing, but it's pretty easy for a geologist to collect unfractured samples. The same for the many other rocks/minerals used in radioisotope dating.At Rock properties I find a table that shows basalt as 0.1% to 1.0% porosity, and granite as 0.5% to 1.5% porosity; that's not very porous for either type, and the granite is more porous than the basalt. I do not know how acurate this reference is, and I do not have other references to hand.I don't know why you are referencing advertising copy on a dietary supplement page, or why you are bringing up tritium. Tritium has a half-life of about twelve years and has no relevance to radioisotope dating. MTBE also has no relevance to radioisotope dating.If you want to demonstrate a problem for radioisotope dating, you need to demonstrate that the 20 or so isotopes are added to or removed from solid un-fractured un-weathered rock in exactly the correct amounts to make multiple radioisotope methods agree and fit the "deeper is older" obervation and make the age agree with non-radiometric methods. Argon, potassium, samarium, neodynium, uranium, lead, thorium, strontium, rubidium, all in multiple isotopes, and a few more I can't think of right now ... and you've got to show that this happens to every rock, not just some rocks. That's a tall order. Vague claims about flow and porosity and diffusion won't cut it. Relevant EVIDENCE is what's required. Most of what you've posted is irrelevant, and the rest is merely wrong.Learn something about radioisotope dating before you criticise it.[This message has been edited by JonF, 01-13-2004][This message has been edited by JonF, 01-13-2004]

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http://www.trinitysprings.com/why.htm
The most compelling evidence of TRINITY's pristine state is the absence of tritium, the pervasive radioactive byproduct of nuclear testing which is found in all surface environments. TRINITY is also free from all other manmade pollutants such as the MTBE gasoline additive which is found underground throughout the United States at an alarming rate.

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Now, lets think about this logically, shall we. I am not a trained geologist, in fact far from it. However, the answer should still be obvious, especially since the half life of tritium is about 11 years. If the well is as old as the carbon dating suggests (16,000 years) the tritium should have decayed away by now. This is more support radioactive measurements, they tend to agree. If this was young water then there should be tritium. The lack of tritium agrees with the 16,000 year age of the spring. This also speaks to the impermiablility of some rocks, as the spring was not contaminated by surface waters that have measurable tritium levels.[This message has been edited by Loudmouth, 01-13-2004]

There is tritium in lots of groundwater and in other places, generated relatively recently by cosmic rays and various human activities. Tritium Information Section, Fact Sheet on Tritium.I have my doubts that the claimed carbon-dating is valid or meaningful, but the page is just an advertisement, and isn't much use as a source of information.

Sandstone that's permeable enough to make decent reservoir rock for oil (and, I presume, for water) has ten times that porosity or better. And, in any case, whatever, porosity is a bulk property of rock. The pores are between grains, where the grains, like zircons, that a geologist hand-picks to do dating on are NOT porous. And argon, yet once again, does not enter into "cationic and anionic exchange" or otherwise give a red rat's ass about chemical reactions of any sort under conditions encountered in rocks.Like JonF said: evidence, please.

Nitpicking: you are correct for so-called "mineral" analysis, and all concordia-discordia dating is mineral analysis because it only works on particular minerals. Some kinds of isochron analysis may be "whole-rock" in which each sample is composed of several minerals; generally an entire rock minus its weathered outer portion. In whole-rock analysis the bulk porosity could be important, but is not because the bulk porosity is so low.

Think your all thinking macro-pores not micro-pores, two things seem to be happening when water flows down by gravity, it flows primarily through the macro-pores, cracks in the basalt, etc... even pressing downward in some instances by reverse osmosis, whatever, but the soil due to surface tension and the forces of capillary osmosis binds water, which of course is the reason plants can grow, as its drawing this water, the minerals in solution, etc...basalt because it has micro-pores too, cause the water to diffuse solutes into the micro-pores, seems the greater the solute concentration it helps the hydralic factors, and on Dual Porosity page 12 Ground-Water Hydrology, Two links, the second link takes you through goggle to the same paper.http://www.hydrology.uga.edu/rasmussen/class/4120/ground.pdf.tidal influence on micropore diffusion - Google SearchIt says that water will tend to bypass the micro-pores but over time the micro-pores will have the same concentrations as the macro-pores, and as water percolates down, the micro-pores will leak into the fresher waters, etc...P.S. I realize you consider zircons, basalt, and the granites non porous, but when you consider micro-pores, it fits quite well with argon diffusion and other elemental solutes, as the hydraulics of the water table press upward through the forces of capillary osmosis, etc...If argon is a gas it will tend to rise up via the capillary processes, as the water presses down, and the tidal effects causing the waters in the ground waters to act like an hydraulic pump. I'm reaching a bit, but seems there is much more to osmosis and capillary water moving up into the nonporous basalts, zircons, granites, micro-pores than mets the eye, with the solutes leaking out of the micro-pores, would cause minerals to continue to be drawn up into the micro-pores of the zircons, basalts, granites, over time, in a proportional ratio, causing the other dating methods to agree, giving the illusion, the rocks are old, etc...It appears zircons are young, too.Acts and Facts Magazine | The Institute for Creation Research[This message has been edited by whatever, 01-14-2004]

In re basalt, nice hand-waving. Now all you have to do is present some EVIDENCE that this actually occurs in basalt and affects the results of radioisotope dating. Note that you need address the question why would so many different elements and isotopes be added or removed in exactly the correct proportions to make so many different methods agree, and follow the "deeper is older" rule?As for the zircons, the votes aren't quite all in on that yet, but it is virtually certain to be another creationist deception. What about Humphreys excess helium arguments, Re: helium in zircons means young earth?.[This message has been edited by JonF, 01-14-2004][This message has been edited by JonF, 01-14-2004]