Supplementary materials for 1

2

Seismic attenuation structure of southern Peruvian subduction system 3

Hyoihn Jang1, YoungHee Kim1*, Hobin Lim1, Robert W. Clayton2 4

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1 School of Earth and Environment Sciences, Seoul National University, Seoul, 08826, Republic of 6

Korea 7

2 Seismological Laboratory, California Institute of Technology, Pasadena CA 91125, United States 8

* Corresponding author 9

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Contents of this file 11

In this file, we show projected location of Nazca Ridge and Nazca fracture zone in a map-view 12

figure (Supplementary Fig. S1), 3D geometrical model for ray tracing (Supplementary Fig. S2), 13

checkerboard test results in horizontal slices (Supplementary Fig. S3), and horizontal slices of QP and 14

QS (Supplementary Figs. S4 and S5, respectively). 15

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Supplementary Fig. S1. Projected locations of the subducting Nazca Ridge (NR) and Nazca fracture 18

zone (NF). See Fig. 1 for symbols and abbreviations. 19

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Supplementary Fig. S2. 3D geometrical model for ray tracing. This model incudes interfaces such 22

as mid-crust, Moho, and top and bottom interfaces of the subducting oceanic crust. 23

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Supplementary Fig. 3. Checkerboard test results for QP and QS at depths of (a–c) 75 km, (d–f) 90 km, 27

and (d–f) 150 km. Initial QP and QS structures ranging from 50 to 500 are shown in (a), (d), and (g). 28

Recovered QP are shown in (b), (e), and (h) and QS in (c), (f), and (i). Note that the initial QP and QS 29

for the inversions are set as 200. See Fig. 4 for the horizontal slice results at 45 and 120 km. See Fig. 30

1 for symbols. 31

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Supplementary Fig. S4. Horizontal slices of QP. Depth of each slice is indicated at upper right 34

corner of each subfigure. See Fig. 1 for symbols. NR—Nazca Ridge. NF—Nazca fracture zone. 35

WC—Western Cordillera. EC—Eastern Cordillera. AP—Altiplano Plateau. SZ—Subandean Zone. 36

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Supplementary Fig. S5. Horizontal slices of QS. Depth of each slice is indicated at upper right 39

corner of each subfigure. See Fig. 1 for symbols. NR—Nazca Ridge. NF—Nazca fracture zone. 40

WC—Western Cordillera. EC—Eastern Cordillera. AP—Altiplano Plateau. SZ—Subandean Zone. 41

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