Watch this video to find out how we use index fossils to establish the relative ages of rocks.

In previous lessons, we talked about the Geologic Time Scale and how scientists use it to piece together the history of the earth.

relative dating interactive activity-12

He began to identify rock layers by the fossils they contained, and he even noticed that the general order of strata was identical over many different parts of the country.

Smith was the first person to understand the principle of fossil succession.

We talked about relative dating of rocks and how scientists use stratigraphic succession to compare the ages of different rock layers.

You should already understand that the lower rock strata are generally older than the strata found higher up in the rock.

In this topic we will learn about the beginnings of Earth.

From its early formation to present, Earth has undergone extreme changes and evolved to be one of the most unique planets in our solar system.In this chapter, we will discover the relationships between weather variables and see how a change in one can affect a change in another.We will focus on different types of weather patterns and see why certain regions have different atmospheric conditions.We will also focus on agents of erosion and be able to identify their different geologic features.Moreover, this chapter will revisit sedimentary rocks and see how the sediments produced during weathering factor into the formation of the different rocks.In this topic we will focus on long term weather patterns and see how the changing Earth is responsible for creating unique areas of our planet.