Erratum to Broadband synthetic seismograms for magnitude 9 earthquakes on the Cascadia megathrust based on 3D simulations and stochastic synthetics, Part 1: methodology and overall results - Frankel, Arthur; Wirth, Erin; Marafi, Nasser; Vidale, John; Stephenson, William (Bulletin of the Seismological Society of America, 2019)