Dispersion of Sound Waves in Ice Sheets

The most striking thing about these recordings is the synthetic-sounding descending tones caused by the phenomenon of the dispersion of sound waves. The high frequencies of the popping and cracking noises are transmitted faster by the ice than the deeper frequencies, which reach the listener with a time lag as glissandi sinking to almost bottomless depths.

And there’s more: …Sounds like Star Wars Blasters (which they do)

[M]any people were thinking about the cause of such sounds and the resemblance to the famous laser gun sounds in Star Wars. First: the dispersion of sound waves, meaning higher frequencies reach the listeners ears earlier than deeper frequencies, is not only an effect experienced in ice sheets, metal is another solid that can perfectly manipulate the speed of frequencies travelling through the material. Because huge thin metal plates are very rare to find (infinte plate called in physics), long wires are the best to experience the dispersion effect. The longer the wire the stronger the down glissando effect. Slinkies are good toys to demonstrate that.