The deep interior of the Earth - The Solid Earth - page 337

(a)

60 km 140 km

290 km 460 km

700 km 925 km

1225 km 1525 km

1825 km 2125 km

δ V S / V S

(%)

2425 km 2770 km

2
1.5
1
0.5
0
− 0.5

− 1

− 1.5

Figure 8.6. (a) Long-wavelength perturbations of S-wave velocity from a standard
whole-Earth model at depths of 60, 140, 290, 460, 700, 925, 1225, 1525, 1825, 2125,
2425 and 2770 km. The model was calculated using surface-wave phase-velocity
maps, free-oscillation data and long-period body-wave travel times. The gradation in
shading indicates increasing perturbation from the standard model. The maximum
deviations decrease from ≥2% at the top of the upper mantle to ±1% in the lower