The Geologic Story of Mount Rainier A look at the geologic past of one of America's most scenic volcanoes

This audio guide walks listeners through the geological forces that shaped one of the Pacific Northwest’s most striking peaks. It paints a vivid picture of the volcano’s soaring ice‑capped summit, its ragged ridges, and the alpine meadows that bloom around its lower slopes, while reminding us that the mountain is still a living system with the potential for future eruptions. By contrasting the stark rock faces with the surrounding evergreen forests and seasonal snowfields, the narrative helps the audience picture why Mount Rainier feels both timeless and ever‑changing.

The presenter then turns to deep time, tracing the region from a swamp‑filled coastal plain 60 million years ago through successive layers of sandstone, shale, and volcanic ash that record ancient seas, river deltas, and the rise of the Cascade Range. Using clear explanations of how geologists read rock layers, faults, and glacial deposits, listeners learn how each episode of eruption, landslide, and glaciation contributed to the mountain’s present form. The result is a concise, picture‑rich tour that connects the science of plate tectonics and volcanic activity to the everyday landscapes visible from a road trip or a hiking trail.