Geological formation refers to the process by which the Earth's layers and structures are created over millions of years. This occurs through various natural processes, including volcanic activity, erosion, and sedimentation. As rocks break down and are transported, they can accumulate in different areas, forming new layers that eventually harden into sedimentary rock. These formations can tell us a lot about the Earth's history, including past climates and the types of life that existed. For example, the Grand Canyon showcases layers of rock that reveal information about ancient rivers and ecosystems, making it a valuable site for both scientists and visitors alike.