The two sets of figures in this electronic supplement show the full data and model fits for all sites, for the coseismic offsets derived from high-rate GPS, and the coseismic and postseismic offsets derived from the daily position time series. Figure S1a–e shows the high-rate GPS time series and the pre- and postseismic fits used to estimate coseismic displacement for high-rate GPS sites AB48, AB49, AB51, AB43, and AB50. Figures S2a–i show the full daily position time series and model fits for GPS sites AB49, AB51, AB43, AB50, LEV6, BIS5, AIS6, BCSS, and BCPR.
Figure S1. Estimation of the coseismic offset from the high-rate GPS time series using a 5-minute fitting window with a 60 s gap for the seismic waves to die away, for sites (a) AB48, (b) AB49, (c) AB51, (d) AB43, and (e) AB50. Displacements for each site are shown for (top) north, (middle) east, and (bottom) vertical directions. The blue circles show the filtered (Butterworth filter, parameters here) position time series every second, with points connected by a green line to show the seismic wave. The unfiltered time series is averaged before and after the main shock over 5-minute windows to obtain the preseismic and postseismic averages (black lines). Residuals are shown in red. The estimated noise distribution is described in each panel in the form N(xx.x,y.y) for white Gaussian noise with an expectation value of xx.x mm and a sigma of y.y mm. The data were smoothed using a 16th order lowpass Butterworth filter with a cutoff frequency of 0.3 Hz, after application of MSF.
Figure S2. Observed (green circles) and modeled (red lines) daily position time series, for sites (a) AB49, (b) AB51, (c) AB43, (d)AB50, (e) LEV6, (f) BIS5, (g) AIS6, (h) BCSS, and (i) BCPR. Displacements for each site are shown for (top) north, (middle) east, and (bottom) vertical directions. All model parameters, including the secular and periodic motion and the coseismic and postseismic displacements by the 2013 Craig event, are estimated simultaneously. The coefficients a to k of the position model, y(ti)=a+bti+csin(2πti)+dcos(2πti)+esin(4πti)+fcos(4π ti)+gH(ti−teq)+ klog[1+(ti−teq)/τ] H(ti−teq), are listed at the top of each panel in the time series plots. (y(ti) is the component of daily position time series at the daily solution epoch ti, teq is the time of the earthquake, and τ is the time decay constant. The first two terms on the right side of the equation are the initial position a and secular motion with linear rate b, respectively. Coefficients c and d describe the annual periodic motion, and e and f describe the semiannual periodic motion. The last two terms describe the coseismic deformation with magnitude g and postseismic deformation with amplitude k. H is the Heaviside step function.) For sites AB49, AIS6, BCSS, and BCPR (a, g, h, and i), the coseismic and postseismic displacements from the 2012 Haida Gwaii event were also estimated. For these stations, the coefficients g1, k1 and g2, k2 represent the individual coseismic and postseismic parameters associated with the 2012 Haida Gwaii event and the 2013 Craig event.
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