The same applies to intrusions

Ams carbon 14 dating definition

Dalrymple goes to great lengths to explain this away, but I think this figure is very telling, and find his explanations unconvincing. Still another evidence for problems with radiometric dating was given in a recent talk I attended by a man who had been an evolutionist and taken a course in radiometric dating.

In uranium-lead U-Pb dating of zircon, the zircon is found to exclude initial lead almost completely. We also need to know that no parent or daughter has entered or left the system in the meantime. The measurements should be done in a double-blind manner to insure lack of unconscious bias.

Assuming we start out

Many ancient lava flows are relatively flat, in contrast to modern ones. Assuming we start out with pure parent, as time passes, more and more daughter will be produced. In general, the dates that are obtained by radiometric methods are in the hundreds of millions of years range.

We now consider whether they can explain the observed dates. In fact, it probably rises to the top of the magma, artificially increasing its concentration there. In fact, if a rock can absorb only a ten millionth part of argon, that should be enough to raise its K-Ar age to over million years, assuming an average amounts of potassium.

Specifically, he quotes one of his anonymous friends that claims that argon easily diffuses from minerals p. Not infrequently such resetting of the radiometric clocks is assumed in order to explain disagreements between different measurements of rock ages. This type of lava typically forms granite or quartz. It is not intended to be natural, but to demonstrate a mathematical fact. Both facts will tend to produce artificially high K-Ar ages in these flows which will not be seen in modern lava flows in the same manner.

Even if crystals exclude argon as they form, argon will rapidly diffuse into them as the lava cools, by the diffusion equation mentioned above. But there are quite a number of rather outstanding anomalies in radiometric dating that creationists have collected. And let me recall that both potassium and argon are water soluble, and argon is mobile in rock. He cites another reference that most igneous bodies have wide biostrategraphic limits. So there would have been a lot more excess argon in the past, leading to older ages.

Many dates give values near the accepted ones. As the magma or lava cools, this path will consist entirely of hot magma or lava, and so the argon will have a free path, and will continue to enter the magma as it cools. It would be difficult to measure the tiny changes in concentration that would suffice to make large changes in the radiometric ages over long time periods. Thus even the existence of correlations is not conclusive evidence that a date is correct.

Thus modern lava flows are not subject to the same mechanism of artificial increases in their K-Ar ages as are ancient ones. Thus we can date lava by K-Ar dating to determine its age. The biostrategraphic limits issue The issue about igneous bodies may need additional clarification. So argon is being produced throughout the earth's crust, and in the magma, all the time. They would all have excess argon due to this movement.

Thus the decreasing K-Ar ages would represent the passage of time, but not necessarily related to their absolute radiometric ages. One study found some correlated dates from bentonite that are used to estimate the date of the K-T boundary. There may be evidence of heating, but the date may be accepted, and there may be no such evidence, but a hypothetical heating event is assumed anyway. The only correlation I know about that has been studied is between K-Ar and Rb-Sr dating on precambrian rock.

Many ancient lava flows