Waveform (Infrasound) Interpretation (3)
Seismology in
the atmosphere is much easier to model for the following reasons:
1)The
atmosphere is a fluid and only supports P-wave or compressional waves
2)The
atmosphere is largely devoid of scatterers (at least for infrasonic
wavelengths)
3)The
atmosphere is relatively isotropic (i.e., the velocity structure is
relatively homogeneous) at least for local recorded acoustic
energy.
4)The
atmosphere is a relatively low dissipative medium (i.e, attenuation for
infrasonic wavelengths is negligible for locally recorded
infrasound.
As a
result, infrasonic Green’s functions are simple and what we record is very
often similar to the original source-time function
* * =
S(t) G(t) I(t)
W(t)
