Eyewitness to an Exploding Volcano: Mount St. Helens

In 1980, Keith Ronnholm was a graduate student in the geophysics program at the University of Washington. On May 18, he was camped at Bear Meadows, 10 miles from Mount St. Helens, and captured photographs of the explosive eruption, before racing away from the onrushing blast cloud and dodging falling rocks. He has an extensive collection of eyewitness photos from numerous vantage points, and he will narrate the events of that morning and discuss how the mountain has evolved since that time. The talk will be a visual treat — many of Keith's pictures are unique and different from the usual photos of the eruption. Plan to attend via Zoom on 1/10/25 as this talk will not be recorded and will be online only this month!

Register for Zoom event here.

Speaker Bio:

Now retired, Keith Ronnholm was a research scientist with the University of Washington Joint Institute for the Atmospheric and Ocean (JISAO), deploying and maintaining climate monitoring buoys for NOAA.

Sand injectites and other soft sediment deformation features formed by megafloods in Oregon, Washington, and Idaho

The Missoula Floods left behind thousands of curious soft-sediment deformation features in their wake. Join us for a photographic tour of these striking features which include sheeted sand dikes, T-shaped mud squirts, flame structures, and rubbly injectites. We will journey down the entire length of the floodway - from Priest Lake to Portland - discovering along the way where each type of feature formed and the geologic reasons why. 

Register for the Zoom event here

Speaker Bio:

Skye Cooley grew up on Samish Island in northern Puget Sound. He received degrees in Geology from Whitman College (BA) and University of Wyoming (MS). He is a field geologist interested in ancient soils, geomorphology, and the interplay between tectonics, topography, and climate. He is currently mapping the glacial deposits in the Mission Valley, MT. He is employed as the Hydrologist for the federally-owned Flathead Indian Irrigation Project in Mission Valley, MT.

Look for field trip description postings about 3 weeks before each trip!

Hazards from the Nevado del Ruiz and Mount Rainier volcanoes — Leveraging lessons learned to prevent future disasters

Mount Rainier in the central Cascade Range of the U.S. and Nevado del Ruiz near the northern end of the Andes volcanic chain in Columbia exist a hemisphere apart. Similarities in their geographies, structures, eruption processes, and hazards make them an ideal couple for comparison and instruction. Both edifices contain weak and collapse-prone rock mantled by glacially distributed rock debris. Five major rivers descend each volcano within narrow valleys that serve as conduits for lahars. 

At Mount Rainier, evidence of a lahar 500 years ago comes alive in a scant extent of oral traditions. At Nevado del Ruiz, memories remain tender and just below the surface for survivors of a 1985 lahar that caused an estimated 25,000 fatalities. During this 40-year anniversary of that catastrophic lahar, we examine an exchange program that brings together public officials and educators of each nation for purposes of education, motivation, and exchange of best practices. We demonstrate that for improvements in risk reduction, commitment to motivating populations may be as important as understanding the nature of a volcano, and that a whole community approach is necessary to maintain preparedness for high consequence/low frequency volcanic events.

Register for the Zoom event here

Speaker Bio:

Carolyn Driedger is a Hydrologist now working in Scientist Emerita status at the U. S. Geological Survey's Cascades Volcano Observatory (CVO) in Vancouver, Washington. Her science career began in 1978 with research on glaciers and glacier-related hazards in Alaska and the Cascade Range. Carolyn witnessed the May 18, 1980 catastrophic eruption of Mount St. Helens and participated in the scientific response. The experience provided an opportunity for observation and reflection about the roles of scientists in society. It set the course for participation in multiple projects across science and societal disciplines. As the USGS-CVO long-term Outreach Coordinator, Carolyn has worked in partnership with public officials, emergency planners, media, park interpreters, and educators to advance the cause of eruption preparedness.