Determining the age of the earth: 

A Rising Tide Project for Grades 9 and 10

Earth Science

            C. The origin and Evolution of the Earth System

2. Geologic time can be estimated by observing rock sequences and by using fossils to correlate the sequences at various locations.  Current methods include using the known decay rates of radioactive isotopes present in the rock to measure the time since the rock formed.

a. Trace the historical development of relative dating using rock sequences and fossils including the contributions of Hutton (uniformitarianism) and Lyell (cross-cutting relationships) and intrusions.