How would you do this

Hi guys i was wondering how one would go about creating the intial sphere bubble texture.

This initial implosion looks like a distortion shader using a circle normal map in front of another texture. Something like this but with the rim of a bubble added.

REM118 shows the concept of that shader here

The aftermath/escaping bubbles look like a flipbooked stock video, but could be simulated too using houdini/maya/3dsmax.