I this case, the isotope is considered a radioactive form of an element.
Many elements have both stable and radioactive isotopes.
Make sure to include when erosion and deformation occurred.
When you are finished check your work with the answers provided.
It is conceptually important that each rock has an origin in concepts of place, time, and physical and chemical conditions. These changes may be rapid (such as a volcanic explosion) or gradual, taking place over millions or billions of years, and involving movement over great distances, both at the surface or to deep within the Earth's crust below us.
However, most rocks we see around us form very slowly in settings that are not visible on the land surface.Slow processes creating rocks can be inferred by observing reefs growing in the oceans, or sediments being carried by flowing water in streams or moved by waves crashing on beaches.We can see sediments being deposited, but we cannot see them turning into stone because the process may take thousand or even millions of years.The chemical composition of Earth's crust has similarities with other stony planets, with silicate-rich rocks being dominant in most locations on the surface.In addition, basic geologic principles can be applied to resolving the order of events leading to the formation of rocks and landscape features. Cross Sections - interpretations of vertical views of geologic features below the surface.Below are two cross sections for use practicing the application of the principles of relative age dating.