Rivers, Beaches, and Sand Dunes: What Do They Look Like When They Turn to Rock?

Led by: William W. Little and David A. Little

We all enjoy floating on a river or enjoying the crashing of waves on a beach. Such features have existed throughout Earth’s history. How do geologists recognize them in the rock record?

Here are two one-day field trips to explore beautiful exposures of ancient sedimentary environments, such as rivers, beaches, and sand dunes and explore the processes that formed them millions of years ago. 

The Notch | Saturday

This is a narrow slot canyon located just south of I-70 about 20 miles west of the town of Green River. It opens to reveal the back and forth change between ancient rivers (like the modern South Platte) and sand dunes (similar to the modern Sahara Desert). We will see both from afar and up close the manner in which sediment accumulated and was then preserved such that we can identify these features today.

Gentile Wash | Sunday

This is a small canyon located just north of the town of Helper on the west side of U.S. Highway 6. In this canyon, we will view the manner in which ancient deltas formed, such as the modern Mississippi and Nile deltas. Additionally, we can observe an ancient record of changing sea level and how that is manifest in the rock record.