Erin Wirth Moriarty
Professional name: Erin A. Wirth
My research focuses on earthquake hazards, specifically in subduction zone settings. I am currently using 3-D numerical simulations to predict earthquake ground motions associated with large (i.e., magnitude 9) earthquakes in the Cascadia subduction zone. I integrate my work with geologic and geophysical observations from previous earthquakes, as well as work closely with engineers and social scientists to improve earthquake resilience in the Pacific Northwest. I am also interested in the generation of strong ground motions by distinct patches on the megathrust (i.e., as observed in the 2011 M9.0 Tohoku, Japan earthquake) and the amplification of ground motions by deep sedimentary basins (e.g., the Seattle basin).
My other research interests focus on using seismic observations and numerical modeling to characterize the structure and dynamics of Earth’s interior. Previously, I have used seismological techniques (such as receiver functions and shear wave splitting) to interrogate deformational processes and the extent of hydration in subduction systems worldwide.
2014 Ph.D. Geology & Geophysics, Yale University
2011 M.Phil. Geology & Geophysics, Yale University
2009 B.S. Physics, New York University
2017-Present Research Geophysicist, U.S. Geological Survey, Seattle, WA
2017-Present Affiliate Assistant Professor, University of Washington
2014-Present Duty Seismologist, Pacific Northwest Seismic Network, University of Washington
2014-2017 Postdoctoral Research Associate, Department of Earth & Space Sciences, University of Washington
2009-2014 Graduate Student Researcher, Department of Geology & Geophysics, Yale University
(*denotes undergraduate advisee, #denotes graduate student)
 Wirth, E. A., Chang, S. W., and Frankel, A. D., 2018. 2018 report on incorporating sedimentary basin response into the design of tall buildings in Seattle, Washington: U.S. Geological Survey Open-File Report 2018-1149, 19p., doi:10.3133/ofr20181149.
 Wirth, E. A., Frankel, A. D., #Marafi, N., Vidale, J. E., Stephenson, W. J., 2018. Broadband synthetic seismograms for magnitude 9 earthquakes on the Cascadia megathrust based on 3-D simulations and stochastic synthetics (Part 2): Rupture Parameters and variability. Bulletin of the Seismological Society of America, doi:10.1785/0120180029.
 Frankel, A. D., Wirth, E. A., #Marafi, N., Vidale, J. E., Stephenson, W. J., 2018. Broadband synthetic seismograms for magnitude 9 earthquakes on the Cascadia megathrust based on 3-D simulations and stochastic synthetics (Part 1): Methodology and overall results. Bulletin of the Seismological Society of America, doi:10.1785/0120180034.
 *Krueger, H. E., Wirth, E. A., 2017. Investigating segmentation in Cascadia: Anisotropic crustal structures and mantle wedge serpentinization from receiver functions. Geochemistry, Geophysics, Geosystems, doi:10.1002/2017GC007064.
 Long, M. D., Ford, H. A., *Abrahams, L., Wirth, E. A., 2017. The seismic signature of lithospheric deformation beneath eastern North America due to Grenville and Appalachian orogenesis. Lithosphere, 9(6), 987-1001.
 #Marafi, N. A., Eberhard, M. O., Berman, J. W., Wirth, E. A., Frankel, A. D., 2017. Effects of deep basins on structural collapse during large subduction earthquakes. Earthquake Spectra, 33(3), 963-997.
 Wirth, E. A., Frankel, A. D., Vidale, J. E., 2017. Generating broadband ground motions for subduction zone earthquakes – Application to the 2003 Mw 8.3 Tokachi-Oki event. Bulletin of the Seismological Society of America, doi:10.1785/0120170065.
 Wirth, E. A., Long, M. D., Moriarty, J. C., 2016. A Markov chain Monte Carlo approach to forward modeling anisotropic receiver functions. Geophysical Journal International, doi:10.1093/gji/ggw383.
 Ford, H. A., Long, M. D., Wirth, E. A., 2016. Mid-lithospheric discontinuities and complex anisotropic layering in the mantle lithosphere beneath the Wyoming and Superior Provinces. Journal of Geophysical Research, doi:10.1002/2016JB012978.
 Wirth, E. A., Long, M. D., 2014. A contrast in anisotropy across mid-lithospheric discontinuities beneath the central United States - A relic of craton formation. Geology, 42, 851-854.
 *McCormack, K., Wirth, E. A., Long, M. D., 2013. B-type olivine fabric and mantle wedge serpentinization beneath the Ryukyu arc. Geophysical Research Letters, 40, 1697-1702, doi:10.1002/grl.50369.
 Long, M. D., Wirth, E. A., 2013. Mantle flow in subduction systems: The wedge flow field and implications for wedge processes. Journal of Geophysical Research, 118, doi:10.1002/jgrb.50063.
 Wirth, E. A., Korenaga, J., 2012. Small-scale convection in the subduction zone mantle wedge. Earth and Planetary Science Letters, 357-358, 111-118.
 Wirth, E. A., Long, M. D., 2012. Multiple layers of seismic anisotropy and a low-velocity region in the mantle wedge beneath Japan: Evidence from teleseismic receiver functions. Geochemistry, Geophysics, Geosystems, 13, Q08005, doi:10.1029/2012GC004180.
 Wirth, E., Long, M. D., 2010. Frequency-dependent shear wave splitting beneath the Japan and Izu-Bonin subduction zones. Physics of the Earth and Planetary Interiors, 181, 141- 154.
 Huggins, P. J., Mauron, N., Wirth, E. A., 2009. The shapes of AGB envelopes as probes of binary companions. Monthly Notices of the Royal Astronomical Society, 396, 1805-1814.