Geologic Past

Ancient lava flows from a magma hotspot created the Columbia River basalts. The old Columbia River eroded and deposited sediments that contain fossils of Pleistocene creatures. Massive floods during the last Ice Age carved the landscape and moved boulders across the northwest. We can see evidence of all these events in the land and rocks around us.  

Explore these pages for more information and education activities about the dramatic geologic past of the Mid-Columbia River region. 

For guided investigations, schedule a program with REACH Educators for your class or other group of learners through our Virtual Field Trip program.

Learn about
Tri-Cities Rocks!

Learn more about Basalt Floods HERE!

Learn more about Ringold Formation HERE!

Learn more about Ice Age Floods HERE!