OLLI 1053 - Field Trip to Big Four Ice Caves

Course Description

Join Dale Lehman, a local geologist, on a guided walk along the Big Four Ice Caves Trail to explore a landscape of 50 million year old sedimentary rocks that tectonic forces have tilted up to form Big Four Mountain. This easy-to-moderate hike along a gravel and boardwalk path leads to the base of the 4,000 ft tall flank of Big Four Mountain. At the mountain's base is 150 foot tall edifice of snow that is resupplied each year as avalaches from high up on the mountain roar down to provide fresh snow. Meltwater that flows between the mountain's bedrock and the snow produces large ice caves, which most years persist through the summer season. Along the way, your guide will explain the origin of the local sandstone and conglomerate and the changing river dynamics which formed them. The tour blends geology with insights into the history and ecology of the region. 

*Please note transportation is not provided.  We will meet at the trail which is about an hour north of the Seattle area. The walk is considered "easy" for difficulty and is one mile each way.