Hi Dave,

I believe that animation is purely for illustration of particle motion =
for P wave propagation, i.e. they are like compression-dilation waves =
like acoustic waves but nothing is implied about the direction of =
propagation in the Earth.

In reality P waves arrive from many different angles (azimuths and dips) =
at a station depending on the relative location.  For far regional or =
distant earthquakes the arrival angle for P waves is often nearly =
vertical, combined with less noisy vertical sensor recordings it is =
common to see clearer P wave arrivals on the vertical component.

Chad


On Mar 24, 2011, at 12:57 PM, Dave Nelson wrote:

>=20
>> Found what I was looking for ,,,,,  a animation of a P wave
>=20
> http://www.geo.mtu.edu/UPSeis/images/P-wave_animation.gif
>=20
> notice there is NO vertical motion, it is totally longitudinal
> P waves travel like sound waves do  :)
>=20
> cheers
> Dave
>=20



Found what I =
was looking for
,,,,,  a animation of a P wave


http://www.geo.mtu.edu/UPSeis/images/P-wave_animation.g=
if


notice there is NO vertical motion, it is totally longitudinal

P waves travel like sound waves do  :)


cheers

Dave



=