# Use radiometric dating in a sentence

(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.This will be discussed in more detail in the section on Gill's paper below.

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.

Note that the mere existence of these assumptions do not render the simpler dating methods entirely useless.

In many cases, there are independent cues (such as geologic setting or the chemistry of the specimen) which can suggest that such assumptions are entirely reasonable.

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.

A routine statistical operation on the set of data yields both a slope of the best-fit line (an age) and a variance in the slope (an uncertainty in the age).