The Changing Landscape of 12-60 Million Years Ago Thumbnail Biography of Mount Rainier Landslides and Mudflows Past, Present, and Future Eunice Lake, northwest of Mount Rainier. The lake lies in a small bedrock basin that was scoured out by a glacier between about 15,000 and 20,000 years ago. The rounded green slopes at the far edge of the lake are underlain by rock that has been smoothed and grooved by glacier ice. This side of Mount Rainier rises to Liberty Cap, which hides the true summit of the volcano. The Geologic Story |