Washington is alive with geologic activity: It's home to the most active volcanoes in the lower 48, earthquakes regularly rattle the populated Puget Sound region, the potential of landslides increases with each soaking rain, and tsunami evacuation routes alert tourists in Olympic National Park to the active plate boundary just off the coast. The only geologic hazard Washingtonians need not fear, at least not with the continued trend of global warming, is another Ice Age flood. More than forty of the biggest floods known in the history of Earth scoured the Channeled Scabland of eastern Washington, the most recent only about 15,000 years ago. Since the first edition of Roadside Geology of Washington appeared on the book shelves in 1984, several generations of geologists have studied the wild assortment of rocks in the Evergreen State, from 45-million-year-old sandstone exposed in sea cliffs at Cape Flattery to 1.4-billion-year-old sandstone near Spokane. In between are the rugged granitic and metamorphic peaks of the North Cascades, the volcanic flows of Mt. Rainier and the other active volcanoes of the Cascade magmatic arc, and the 2-mile-thick flood basalts of the Columbia Basin. With the help of this brand new, completely updated second edition, you can appreciate spectacular geologic features along more than forty of Washington's highways.
Darrel S. Cowan received his BS and PhD in geology from Stanford University and served as an exploration geologist in the Alaska Division of Shell Oil Company from 1971 until 1974. He accepted a faculty position at the University of Washington in Seattle in 1974 and currently teaches in the Department of Earth and Space Sciences. Darrel's research interests include processes at ancient subduction zones and the late Mesozoic tectonic evolution of the western margin of North America. Although his field research has taken him and his students all over the world, the San Juan Islands in Washington rank high on his list of geologic puzzles worthy of study. In 2014, Darrel received the Career Contribution Award from the Division of Structural Geology and Tectonics of the Geological Society of America.