There was a time in the geologic past when Washington and Oregon didn’t exist and an ocean flooded inland across Idaho. Many of the rocks that make up the Boulder, Pioneer, Smoky, and White Cloud Mountains were formed in this oceanic setting.

Join Dr. Paul Link of Idaho State University for a morning lecture and afternoon roadside field trip where you’ll learn the remarkable story of how this ocean formed and how rock that amassed below sea level became the highly elevated land that surrounds us today. The field trip will follow Trail Creek Road to Trail Creek Summit and continue 7 miles beyond the summit to the North Fork of the Big Lost River.

This full-day class is limited to 20 students. Pre-registration is required. The one-hour lecture begins at 10:30 a.m. in the Library's Lecture Hall, then the group will eat lunch before heading into the field. Bring your own lunch, snacks, water, and a car (carpooling for the afternoon is encouraged!), and lots of curiosity. The group will return to Ketchum no later than 6:00 p.m.

All attendees are responsible for their own safety during the field portion of this class. The field portion involves riding in a car with yourself or others, stopping at points of interest, and some light walking. 

Paul's presentation will also be recorded for later viewing through the Library's Program Archive.

Paul K. Link is Professor Emeritus in the Idaho State University Geology Department. He started in 1980 and retired in 2020. He has a B.S. from Yale, and graduate degrees from the University of Adelaide, South Australia, and the University of California, Santa Barbara. He was ISU Geolology Department Chair from 1986 to 1992. Before coming to ISU he was a Mountaineering Instructor at the National Outdoor Leadership School (NOLS) in Lander, Wyoming. In the 1980s he and about 15 Masters Students worked U.S. Geological Survey field geology projects in the Ketchum area. For 15 years he directed the ISU Geology Field Camp at the Lost River Field Station north of Mackay, Idaho. He supervised over 100 M.S. students. He is co-author of the 2012 Idaho State Geologic Map, the book Rocks, Rails, and Trails, and the 2021 2nd edition of the Roadside Geology of Idaho.