Sedimentary rocks are created by natural processes but are also altered by natural processes. An understanding of these processes sometimes allows geoscientists to assemble a great deal of information about the subsurface from small surface clues. In this section, we briefly discuss general principles that geoscientists follow in evaluating rock formations. You’ll never again think that rocks are boring when you understand the rich history that they can reveal!

Duration: Approximately 10 minutes, depending on user pace.

Learning Objectives: Upon successful completion of this module, you will be able to:

• Describe why sediment deposits differ over time, creating rock layers with varying characteristics
• Discuss how continued accumulation of sediments can cause older rock layers to become buried deeply underground
• List ways that rock layers can be changed over time and how geoscientists can identify some of the changes that have occurred
• Explain how fossils can be used to estimate the age of rock layers and the conditions in which the layers were deposited
• Convey how exposed rock at the surface can provide important clues about the structure and characteristics of rock layers underground

Prerequisites: Module 1-3

Advance Preparation: None

Program Level: Non-technical

Format: Prerecorded narrator with supporting visuals. User controls course pace.