Uranium Dating

I really like this analogy. Your digital watch might be wrong, your friend's analog watch might be wrong, your other friend's watch synchronized to the signal from the National Bureau of Standards time signal might be wrong, your computer clock might be wrong, your grandfather's wind-up watch might be wrong, everyone else's watch in town might be wrong, but what would be the odds that they all give the same wrong time?Creationists require long odds like these to not only come through but to have a rational and natural explanation.--PercyEdited by Percy, : Grammar.

Quotes are really easy. A quote begins with [qs], and it ends with [/qs]. For example, this:Will end up looking like this: If you want to include the name of the person the quote is from then just include the name in the opening quote after an "=" like this: And that will end up looking like this: Moving on to the rest of your post: So how is the real world like your analogy where everyone in town sets their clocks and watches according to one central clock? In the real world, what is the central clock for the many types of radiometric dating, geological layers, fossils, lake varves, glacial ice layers and tree rings? Ah, yes, the vast scientific conspiracy that happens to include many scientists who are Bible-believing Christians.--Percy

Hi Everyone!Adminnemooseus is now on duty in this thread, so I'm going to switch to being a normal participant. Ohboyohboyohboyohboy! Hi Archaeologist!You're obviously strongly influenced by what you believe the Bible says. You believe not only that Biblical testimony trumps real world evidence, but that your interpretation of the Bible trumps anyone else's outside your faith group and that it even gives you the right to declare who is a Christian and who is not.But while it's fascinating watching someone demonstrate fundamentalist faith in real time, that's not what this thread is about. If you'd like to discuss the Biblical foundation for your faith then there are many threads for that over in The Bible: Accuracy and Inerrancy. Here in forums like this one we discuss the scientific evidence.Most of your objections to dating methods seem to be based upon a belief that we couldn't possibly know with any certainty what we claim to know. Rest assured that we can know these things with as much certainty as that Lincoln and the Civil War occurred in the 19th century. If you truly believe that much uncertainty surrounds Lincoln and the Civil War then there's no point in trying to convince you of anything, so if you were serious about that then it would be good to know up front so that those presenting science to you can make an informed decision about whether they're wasting their time. There are very few places on Earth where the rocks approach 4 billion years in age, but Greenland is one of those places. Here's a table of references to scientific papers that dated rocks from Greenland, taken from Brent Dalrymple's The Age of the Earth. Click to grow the image to readable size: Another of your concerns is about sample contamination: With isochron dating, a contaminated sample does not yield a straight line. When the analysis yields a straight line it means no contamination occurred. This graph and the caption is from Radiometric Dating: A Christian Perspective:

Figure 4. A rubidium-strontium three-isotope plot. When a rock cools, all its minerals have the same ratio of strontium-87 to strontium-86, though they have varying amounts of rubidium. As the rock ages, the rubidium decreases by changing to strontium-87, as shown by the dotted arrows. Minerals with more rubidium gain more strontium-87, while those with less rubidium do not change as much. Notice that at any given time, the minerals all line up--a check to ensure that the system has not been disturbed.

Another of your concerns was how we could know the original concentration of daughter material. As you can see in this graph, the original concentration is the Y-intercept:

Figure 5. The original amount of the daughter strontium-87 can be precisely determined from the present-day composition by extending the line through the data points back to rubidium-87 = 0. This works because if there were no rubidium-87 in the sample, the strontium composition would not change. The slope of the line is used to determine the age of the sample.

Uranium dating, the topic of this thread, is not an isochron method, which means that independent methods must be used to determine the original amount of daughter material, and this isn't always possible with the necessary accuracy. Those of you active in the field please correct me if I am wrong, but I don't believe plain old U/Pb dating is a commonly used dating method today.--Percy

There are over 30 forums at EvC Forum covering a wide range of topics. You can discuss pretty much anything you like here as long you stay roughly on-topic in any given thread. This is from the Forum Guidelines:

2. Please stay on topic for a thread. Open a new thread for new topics.

In the science forums we discuss topics from a scientific perspective, and there's even a forum for discussing alternative approaches to science: Is It Science?. If you really believe the playing field is tilted in the direction of science and would like to discuss how the rules should change then that's the place to do it. We wouldn't be here if we didn't want to hear your viewpoints. Expressed in threads where they're on-topic, of course.Objectivity is an ideal that science approaches by developing consensus through the gathering of evidence and making successful predictions. In science theories aren't thought true because they are widely accepted. Rather, theories become widely accepted because they are likely true due to the presence of a broadly interconnected network of persuasive supporting evidence and successful predictions. I think you must have a mistaken impression about the nature of certainty within science. In science nothing is known for certain. This is known as the principle of tentativity. In science all knowledge is considered tentative and open to change in light of new evidence or improved insight.This means that at EvC Forum you are welcome to cast as much doubt as you like upon anything within science. Your argument about possible contamination is an example of taking this very valid approach. If you have actual arguments against the evidence presented to you then this is the place to make them.By the way, your views are not disallowed, but you may find that you'll have to take different views to different forums. Views that the rules of science should change are discussed in threads in the Is It Science? forum. We take this approach because otherwise those with this view use it in every thread in all the other forums, and this causes the topic of discussion in multiple threads to become whether God and Bible should be accepted as scientific evidence. In order to insure that threads stay on their original topic we centralize such views in the Is It Science? forum. If you have an argument based upon those links then please present it yourself in your own words and use the links as references. This is rule 5 from the Forum Guidelines:

5. Bare links with no supporting discussion should be avoided. Make the argument in your own words and use links as supporting references.

--Percy