What is the difference between radioactive decay and radiometric dating
In the liquid or gaseous state, however, particles can move around and boil off.
Because of radioactive decay, the material starts out with a larger amount of daughter isotope than is chemically favorable, so some of it will escape to bring the material to equilibrium.
Think of air bubbles frozen in an ice cube--the air is prevented from escaping by the solid ice, but will escape when the cube melts because the energy of the system is lower without the bubbles.
(Further separation could occur during solidification, due to different crystallizations of the parent and daughter isotopes.) This means that the information about how much decay took place prior to melting is lost.
How is it that melting an asteroid can "reset" its atomic clock?
For example, layers form within glaciers because there tends to be less snowfall in the summertime, allowing a dark layer of dust to accumulate on top of the winter snow (Figure 11.23).It stated that this is possible because each event melted part of it, and thus the atomic clock of that part was reset.So how does melting a stone cause decayed radioactive elements to return to their original form? The same question applies to dating the solar system.The longest cores have helped to form a record of polar climate stretching hundreds of thousands of years back.Another example of yearly layers is the deposition of sediments in lakes, especially the lakes that are located at the end of glaciers.
To study these patterns, scientists drill deep into ice sheets, producing cores hundreds of meters long.