Thorne Lay is Distinguished Professor of Earth and Planetary Sciences at the University of California Santa Cruz. He is a seismologist, and uses seismic wave recordings to study large earthquake ruptures, internal structure of the Earth, and seismic monitoring of nuclear testing treaties. Lay was born in Casper, Wyoming in 1956, and raised in El Paso Texas. He attended the University of Rochester, receiving a B.S. in Geomechanics in 1978. He obtained M.S. and Ph.D. degrees in Geophysics from the California Institute of Technology and was a postdoc there in 1983. Lay then became a faculty member at the University of Michigan, before moving to Santa Cruz in 1990. He has served as Director of the Institute of Tectonics, Chairman of the Earth and Planetary Sciences Department, and Founding Director of the UCSC branch of the Institute of Geophysics and Planetary Physics. He is elected Fellow of the National Academy of Sciences, the American Academy of Arts and Sciences, and the American Association for the Advancement of Science. Lay received the 2015 Harry Fielding Reid Medal of the Seismological Society of America, and the 2014 Inge Lehmann Medal and 1991 Macelwane Medal of the American Geophysical Union

Research Interests

Thorne Lay conducts seismological research using ground motion recordings to quantify the rupture processes of large earthquake, to determine internal structure of the Earth's mantle and core, and to support monitoring of nuclear testing treaties. Throughout his career he has examined ground shaking recordings to determine space-time complexity of seismic energy release from large earthquakes, helping to originate the asperity model of fault surface frictional heterogeneity and its many embellishments. He collaborated with Don Helmberger in discovering a shear velocity discontinuity in the lower mantle that is now generally interpreted as a manifestation of a phase change in the most abundant mantle mineral, silicate perovskite. He analyzes regional and teleseismic recordings of ground shaking to identify and measure the yields of underground explosions. Lay is author of more than 411 research publications including books, articles in refereed books and professional journals, technical reports, book reviews, news items and conference proceedings.

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Primary Section

Section 16: Geophysics

Secondary Section

Section 15: Geology