Seismic Velocity Structure in the Area of the 2007, Mw 8.0, Pisco-Peru Earthquake: Implications for the Mechanics of Subduction in the Vicinity of the Nazca Ridge

Figure 3

Evolution of the (Vp) velocity model and relocated hypocenters through the inversion TomoDD, obtained for the vertical cross-sections (a1, a2), (b1, b2), and (c1, c2) perpendicular to the trench axis, located to the north, center, and south of the Paracas Peninsula. Left: Velocity model obtained after the first iteration. Right: Final velocity model obtained after 30 iterations (last). (derivative weight sum) roughly defines the limit between the high- and low-resolution areas (dashed gray line); the tendency of hypocenter locations is shown by the dashed white lines, and the red star corresponds to the main event epicenter.

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