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ggge20136-sup-0001-suppinfoFigureS1.pdf125KFigure S1. Starting regional velocity model. Offshore, this starting model accounts for bathymetry and sediment velocities. From the seabed to a depth of 8 km beneath the seabed, we fix our velocity model to a spatial average of velocities determined by optimal migration and stacking of MCS data. SAHKEII shot point localities designated as stars and OBS locations are white dots.
ggge20136-sup-0002-suppinfoFigureS2.pdf3498KFigure S2. (a) Rays traced on the final first-arrival tomography model. Only every 4th ray is plotted. (b) Grid of derivative weight sum (DWS). The DWS weights each ray path length according to its spatial separation from the grid node. Larger DWS values indicate better data coverage. SAHKE-II shot point localities designated as stars and OBS locations are white dots.
ggge20136-sup-0003-suppinfoFigureS3.pdf642KFigure S3. Wide-angle CDP stacked images of individual SAHKE-II onshore shots with instantaneous amplitude processing step applied and superimposed on the two-way time converted velocity model shown in Figure 3d; (a) SHOT 12, (b) SHOT 11, (c) SHOTS 9 and 1. The prominent lower crustal reflection, PintP, at the base of pronounced reflectivity, is from the top of the subducted Pacific plate. Crustal reflection, PcP, appears as the top of underplated material and is interpreted as the Wairarapa Fault (A). Other splay faults (B and C) branch from where the plate interface steps down and increases in dip from <5° to >15°, ∼100 km away from the trench. Details of the processing sequence are given in Table S1.
ggge20136-sup-0004-suppinfoFigureS4.pdf18294KFigure S4. Enlarged version of Figure 3e. Marine MCS (SAHKE01, SAHKE02, low-fold SAHKE-II onshore shots) data with the two-way-travel-time (twt) converted velocity model superimposed. Picked horizons and faults are shown in black and dashed where uncertain. The interpretation beneath the central section is from the low fold stack of land explosions (see Figure 7).
ggge20136-sup-0005-suppinfo05.docx20KSupporting Information

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