A formation is a set of rocks grouped together for mapping purposes. A formation consists of layers of the same stratigraphic age. All of the above statements are true. Proterozoic eon 24. Proterozoic eon 25.
Radioactivity is the spontaneous decay of unstable atoms.
The number of radioactive atoms that decay in a given amount of time is proportional to the number of radioactive atoms in the sample. During radioactive decay, radioactive atoms gain energy. The decay of radioactive elements releases X-rays. William Smith 37. All of the above.