,The 1964 Prince William Earthquake
magnitude of 9 2
· .
·
triggered a tsunami which reached Hawaii & Japan
O
139 deaths but most were due to the tsunami
uplifted 11 5m
Land the coast was
by
·
near
.
,
, SEISMIC WAVES
↳ elastic wave
generated by an
eg an earthquake
imprise .
they
travel at several km/S , they provide understanding of the Earth
P-WAVES (primary)
·
longitudinal , pass through solids (liquids
&
·
faster than 5-waves
low
frequency INFRASOUND : < 20Hz
· -
Pass through Mantle (solid)
S-WAVES (secondary) & outer core (liquid)
transverse pass ↓ inner core (solid)
only through solids
·
,
slower than p-waves ↳
↓
·
cannot pass through liquid outer core
This is because liquids cannot
sustaini shear stresses
(transverse)
S
& arrives 10s later than P . V of P-wave is 8km/s
V of S-wave is 4km/S
disp
+s
=
=
+p + 10
ds
%
dp =
Vpxtp =
Vs =
t
8000m/s x(p = 4000 X +s
8000 x Xp = 4000x(tp + 10)
80004p = 4000 +p + 40000
4000
Xp = 10s
d = 5xt
=
8km x I0s
= 80km
magnitude of 9 2
· .
·
triggered a tsunami which reached Hawaii & Japan
O
139 deaths but most were due to the tsunami
uplifted 11 5m
Land the coast was
by
·
near
.
,
, SEISMIC WAVES
↳ elastic wave
generated by an
eg an earthquake
imprise .
they
travel at several km/S , they provide understanding of the Earth
P-WAVES (primary)
·
longitudinal , pass through solids (liquids
&
·
faster than 5-waves
low
frequency INFRASOUND : < 20Hz
· -
Pass through Mantle (solid)
S-WAVES (secondary) & outer core (liquid)
transverse pass ↓ inner core (solid)
only through solids
·
,
slower than p-waves ↳
↓
·
cannot pass through liquid outer core
This is because liquids cannot
sustaini shear stresses
(transverse)
S
& arrives 10s later than P . V of P-wave is 8km/s
V of S-wave is 4km/S
disp
+s
=
=
+p + 10
ds
%
dp =
Vpxtp =
Vs =
t
8000m/s x(p = 4000 X +s
8000 x Xp = 4000x(tp + 10)
80004p = 4000 +p + 40000
4000
Xp = 10s
d = 5xt
=
8km x I0s
= 80km
