Stress m m Refraction Reflection Refraction and Reflection

応力（Stress)

m m

屈折 Refraction Reflection 反射 Refraction and Reflection of a Beam of Light

Comparison of P-wave and Swave Motion SH波とＳＶ波 Ｓ波には二つの振動 モードがある。 極性（Polarization） 8

2種類の表面波 Surface Waves Rayleigh wave レイリー波 Love wave ラブ波

内核の発見(1936) Dr. Inge Lehmann (1888 -1993), 内核の 発見者　　Born in Denmark in 1888 The existence of an inner core distinct from the liquid outer core was discovered in 1936 by seismologist Inge Lehmann[3] using observations of earthquake-generated seismic waves that partly reflect from its boundary and can be detected by sensitive seismographs on the Earth's surface.

Seismic Tomography Scan of a Section of the Mantle Subducted slab Fig. 19. 9

Earthquake terms focus: site of initial rupture 震源：最初に破壊した場所 epicenter: point on surface above the focus 震央：震源上の地表の点

Elastic Rebound Theory Fig. 18. 1 a

Elastic Rebound Theory Fig. 18. 1 b

Elastic Rebound Theory 震央 震源 Fig. 18. 1 c

Elastic Rebound Theory すべり量 Fig. 18. 1 d

Time Lag Between S and P waves as with Distance from Epicenter Fig. 18. 9 a

走時 Seismic Travel-time Curve 走時曲線 傾き　d. T/d△ Slowness (min/km) Fig. 18. 9 b 震央距離　Δ　（度）

Locating the Epicenter Fig. 18. 9 c