The Yellowstone Hotspot: Past, Present, and Future
By Robert Smith
July 27, 2017
Join us for a talk exploring the past, present, and future of the Yellowstone Hotspot, followed by a light reception, hosted by the Center’s Draper Natural History Museum.
About the talk
Yellowstone is truly one of the world’s great volcanoes. It is the result of three supervolcano volcanic eruptions in last 2.1 million years followed by the last giant eruption 640,000 years ago by 60 smaller volcanic flows as young as 70,000 years. Moreover, Yellowstone is the most seismically active area of the western U.S. interior and experienced a deadly M7.3 earthquake in 1959 at Hebgen Lake, Montana, on the west side of the Yellowstone Plateau, that killed 28 persons. Seismicity of Yellowstone is dominantly released in swarms of events i.e. clusters of earthquakes occurring closely in time and space and a common feature of volcanoes. Using earthquake tomography, Smith explains how, through new seismic tomography, we now have three-dimensional pictures of Yellowstone’s 1,000 km-deep mantle plume and its connection to shallow lower- and upper-crustal magma bodies from 40 km to 5 km depth, that provides key information on its magmatic plumbing and how it fuels Yellowstone’s world renown hydrothermal features.
Most recently the University of Utah led scientific experiments to image for the first time the anatomy of Old Faithful and its shallow hydrothermal reservoir, its fluid pathways at depths of 10 to 60 meters, and its temporal variations. Taken together the above information on the interaction of Yellowstone’s volcanic and earthquake processes and how magmatic fluid accumulation in the crustal magma reservoir is transported away from the caldera keeps the Yellowstone magma system safe from eruptions, but conversely how trapping these fluids leads to volcanic eruptions. Smith also demonstrates that large earthquakes—not volcanoes—are the greatest threat to Yellowstone. Says Smith, “Yellowstone has allowed me to bring modern earth science skills into a wondrous experiential outdoor laboratory where I still experience new geologic discoveries nearly every year!”
About our speaker
Robert B. Smith is Distinguished Research Professor of Geophysics and Geology, and Emeritus Professor of Geophysics at the University of Utah. He is also Coordinating Scientist of the Yellowstone Volcano Observatory and Director for the Yellowstone Seismic Network. He holds both a bachelor and master of science degree in geology from Utah State University, and a PhD in geophysics from the University of Utah. Smith has authored more than two hundred full scientific papers—more than 120 of them on Yellowstone-Teton geology—as well as more than five hundred abstracts for lectures around the world. He is the senior-author of the most popular geology book on Grand Teton and Yellowstone National Parks, Windows Into The Earth: The Geologic Story of Yellowstone and Grand Teton National Parks, which has sold more than 40,000 copies.
For more information, e-mail Bonnie Smith or call 307-578-4020.