# Describe process carbon dating

Age "uncertainty" When a "simple" dating method is performed, the result is a single number.There is no good way to tell how close the computed result is likely to be to the actual age.(For brevity's sake, hereafter I will refer to the parent isotope as ).In addition, it requires that these measurements be taken from several different objects which all formed at the same time from a common pool of materials.An additional nice feature of isochron ages is that an "uncertainty" in the age is automatically computed from the fit of the data to a line.

The equation is the one which describes radioactive decay: If one of these assumptions has been violated, the simple computation above yields an incorrect age.

(Rocks which include several different minerals are excellent for this.) Each group of measurements is plotted as a data point on a graph.

The X-axis of the graph is the ratio of in a closed system over time.

Whether there's a data point on the Y-axis or not, the Y-intercept of the line doesn't change as the slope of the isochron line does (as shown in Figure 5).

Therefore, the Y-intercept of the isochron line gives the initial global ratio of could be subtracted out of each sample, and it would then be possible to derive a simple age (by the equation introduced in the first section of this document) for each sample.