Geologists Discover Ancient Colorado River Path

Researchers trace 5.6 million-year-old river route to dried lakebed near Grand Canyon

Apr. 17, 2026 at 7:01pm

Got story updates? Submit your updates here. ›

A highly textured, abstract painting in soft earth tones, featuring sweeping geometric arcs and precise natural spirals, conceptually representing the structural evolution of the Colorado River system over millions of years.An abstract visualization of the Colorado River's ancient path, uncovered by geologists studying the region's geological history.Grand Canyon Village Today

Geologists have uncovered evidence of an ancient path the Colorado River took during the Miocene Epoch, over 5.6 million years ago. The river's former route has been traced to a now-dry lakebed located east-southeast of the Grand Canyon in Arizona.

Why it matters

This discovery provides new insights into the geological history and evolution of the Colorado River system, which has shaped the landscape of the American Southwest over millions of years. Understanding the river's ancient paths can help scientists better model its long-term changes and impacts on the region.

The details

Using geological mapping and analysis, researchers were able to track the Miocene Epoch version of the Colorado River to a dried lakebed situated east-southeast of the present-day Grand Canyon. This ancient river path diverges significantly from the Colorado River's current course, offering a glimpse into the dramatic changes the river system has undergone over vast timescales.

  • The ancient river path dates back over 5.6 million years to the Miocene Epoch.

The players

Geologists

Researchers who used geological mapping and analysis to uncover evidence of the Colorado River's ancient path.

Got photos? Submit your photos here. ›

The takeaway

This discovery highlights the dynamic nature of the Colorado River system and the importance of studying its long-term geological history to better understand the forces that have shaped the American Southwest over millions of years.