About the Talk

Eruption—The Untold Stories of Mt. St. Helens

For months in early 1980, scientists, journalists, sightseers, and nearby residents listened anxiously to rumblings in Mount St. Helens, part of the chain of western volcanoes fueled by the 700-mile-long Cascadia fault.

Still, no one was prepared when an immense eruption took the top off of the mountain and laid waste to hundreds of square miles of verdant forests in southwestern Washington State. The eruption was one of the largest in human history, deposited ash in eleven U.S. states and five Canadian provinces, and caused more than one billion dollars in damage. It killed fifty-seven people, some as far as thirteen miles away from the volcano’s summit.

Shedding new light on the cataclysm, author Steve Olson interweaves the history and science behind this event with page-turning accounts of what happened to those who lived and those who died.

Powerful economic and historical forces influenced the fates of those around the volcano that sunny Sunday morning, including the construction of the nation’s railroads, the harvest of a continent’s vast forests, and the protection of America’s treasured public lands. The eruption of Mount St. Helens revealed how the past is constantly present in the lives of us all. At the same time, it transformed volcanic science, the study of environmental resilience, and, ultimately, our perceptions of what it will take to survive on an increasingly dangerous planet.

Rich with vivid personal stories of lumber tycoons, loggers, volcanologists, and conservationists, Eruption delivers a spellbinding narrative built from the testimonies of those closest to the disaster, and an epic tale of our fraught relationship with the natural world. Steve will have a book signing and sale before and after the lecture. For more information about the Jefferson Land Trust’s Geology Group, visit our website.

About the Speaker

Steve is a freelance writer based in Seattle who has had the good fortune to write about some of the most interesting and important topics of our time, including genetics, race, human origins, evolution, climate change, education, talent, competition, and punk rock music. Here’s a short bio. My most recent book (and the subject of my Geology Group lecture) is Eruption: The Untold Story of Mount St. Helens, which was named one of the 20 best nonfiction books of 2016 by Amazon, was nominated for The Boardman Tasker Prize for Mountain Literature and was an Indie Next selection

About the Talk

Assembling the Pacific Northwest

Two hundred million years ago, the west coast was where Spokane is now. This was the edge of the craton—the old part of the continent. How did the rest of the Pacific Northwest come to be here and where did it come from?

The west coast became an active plate boundary when an oceanic plate started to subduct beneath it. As the oceanic plate subducted, blocks of crust that it carried, such as island arcs or oceanic plateaus, were scraped off and added to the edge of the continent in a process known as accretion, thus building the Pacific Northwest we know it today.

Accreted terranes have a different geologic history than the bodies of rock adjacent to them and are separated from their surroundings by major faults. The Crescent Formation of the Quimper Peninsula, for example, is part of a large accreted terrane that underlies much of the coastal Pacific Northwest. The Crescent Terrane originated as piles of basalt which erupted from the sea floor and in some places built broad oceanic islands. This basalt, along with oceanic sediment, was then shoved against and accreted to the continent. Deep thrust faults separate the Crescent Terrane from terranes that had accreted earlier to the Pacific Northwest. Subsequently, the younger oceanic crust has been added seaward of the Crescent Terrane. Each piece of accreted crust is separated from the others by thrust faults, and the subduction zone continues to shift westward as younger terranes are added to the edge of the continent.

The accreted terranes of the Pacific Northwest are a four-dimensional (in time as well as space) jigsaw puzzle that is still being assembled. Western North America was the main testing ground for the development of the accreted terrane concept. We will delve into the discovery that some Pacific Northwest terranes may have moved north more than a thousand miles along the edge of the continent. We will also discuss the current state of knowledge of accreted terranes in the Pacific Northwest, with the Olympic Peninsula representing the leading edge of the North American continent, where terrane accretion continues today.

About the Speaker

Ralph Dawes is originally from Edmonds, WA. He has a degree in literature from Antioch College in Yellow Springs, OH, and degrees in geology from WWU (BS) and the UW (MS, Ph.D.). He has taught geology for the past 23 years, the last 16 at Wenatchee Valley College. He is passionate about sharing how the geologic history of the Pacific Northwest gives insight into the landslides, floods, volcanic eruptions, and earthquakes of today.

About the Talk

Glaciers of the Olympic National Park—Past, Present, and Future?

Bill Baccus will present an overview of the Glaciers of the Olympic National Park, where he has worked for 30 years. As you may know, the winter of 2014-15 was one of extremely low snowfall in the Park, which has a direct impact on the glaciers. Is this a harbinger of the future?

Bill will introduce the glacial resources at Olympic National Park and discuss the methods used to inventory the park’s glaciers. These include the use of high-resolution aerial photography to delineate glacier perimeters and determine surface area, as well as the use of high-precision GPS to calculate changes in ice thickness. In addition, they have replicated historic photos to provide a visual record of the dramatic changes that have occurred over the past century.

Recent monitoring work on two park glaciers includes a multiple-year study of glacier mass balance which helps us understand the response of glaciers to annual climate variations and provide a more accurate understanding of glacier contributions to Olympic Peninsula rivers. Highlights of that study included the discovery that rates of retreat of Olympic glaciers were substantially higher than other areas of the Pacific Northwest and showed that there has been a loss of nearly a third of our small alpine glaciers, and major changes in both surface area and volume to larger glaciers.

About the Speaker

Bill Baccus is a Physical Scientist with the National Park Service where he works on the North Coast and Cascades Network supporting their long-term monitoring program. He operates a network of climate stations within the park, studies winter snow pack, glaciers, and mountain lakes, and studies coastal ecosystems.