What Sedimentary Rocks Tell You

Overview

Sedimentary rocks—those formed from sediment deposited by water or wind—make up a substantial majority of rocks at Earth’s surface. In this lecture, focus on clastic rocks, which are composed of broken fragments of pre-existing rocks. The fragments can vary in size from clay particles to silt, sand, gravel, and larger pieces. Learn how these rocks form and the rich stories they tell about the past.