However, in Ar-Ar dating the two isotopes of argon are both measured from the same sample, and so at least one potential source of error is eliminated.The other important advantage of Ar-Ar dating is the extra data gained from step heating: instead of heating the irradiated sample to the highest possible temperature all at once, and so releasing all the argon all at once, we can increase the temperature in steps starting at a low temperature. Well, different minerals within the rock will give up their argon at different temperatures, so each step will give us a ratio of K from which these are derived must have appeared in the same ratio in each mineral, because both isotopes of potassium have the same chemical properties.
In this article we shall explain how this method works and why it is superior to the K-Ar method.The reader should be thoroughly familiar with the K-Ar method, as explained in the previous article, before reading any further.Measuring the Ar emitted from the standard, and knowing the time t that it was formed, we can put these figures into the equation above and solve it for J.So now we know J, and we have measured the R-value of the sample we're actually interested in dating, so we can use these data to solve the equation for t, giving us the age we're looking for.For example, if the date increases at each step, then we are quite possibly looking at a slow-cooling igneous rock in which different minerals crystallized out of the magma at different times, a possibility we can investigate further.
Or if we consistently get one date for the steps below (for example) 400°C, and consistently get another date in the steps above 400°C, then it seems as though argon loss occurred as a result of metamorphism at a temperature of about 400°C, with the younger date representing the date of the metamorphism, and the older date representing the formation of the rock; and we can investigate this clue further by looking for other evidence of the metamorphic event.In no event the Product Information or parts hereof shall be regarded as guarantee of conditions or characteristics.The Product Information or any part thereof may also not be regarded as a warranty of any kind.As firmware changes may affect the behavior of the drive/motor sometimes in unexpected ways, pay attention to machine safety and be prepared for unexpected motion.It is a good safety practice to disconnect motor shaft for testing. We will fix firmware issues as first priority task.A crucial point to note is that because K are isotopes of the same element, they have the same chemical properties.